Good afternoon and welcome to today's energy seminar. Isn't it great to have a microphone here, especially with the mask on? Today, we have a real treat. This, I think, is our third annual exposition of the Stanford Energy Student Lecture Honorees. Here, as I can figure, this is a deal where you work really hard in your lab for three or four years. You do exceptional cutting-edge research, and then your advisor nominates you to be included in the competition for the best student technology lectures. And that goes on all summer. I see Richard Sassoon and Maxine Lim, who run it here. And it's kind of like the Olympics. And I'm actually going to let Richard Sassoon. No pressure, you guys. I'm going to introduce my dear friend and colleague, Richard Sassoon, who is currently Dr. Richard Sassoon, who's currently the executive director of the Stanford Energy Alliance. And when I met him, 2003, I see was the managing director of the Global Climate and Energy Project. Please don't ask him for any embarrassing stories about our travel to cutting-edge energy laboratories around the real world. He just told me that he's written this up or was interviewed about this recently. So I'm not interested in seeing that. So without further ado, Richard is a renowned scientist in his own right, a PhD in physical and analytic chemistry, and probably the most knowledgeable person about all aspects of a broad range of energy technologies. I know so Richard's going to introduce the panel and moderate their presentations, which I'm really looking forward to hearing from Richard. Thank you, John. I won't embarrass you today, don't worry. So welcome to this session where we showcase some of our top student researchers. This year, we're delighted to have four speakers who have been honored as 2021 Stanford Energy Distinguished Student Lecturers. So as many of you may already know, we hold this annual Stanford Energy Student Lecture Series every summer. And this year represents the 11th time that we've conducted this program. The goal of the program is really twofold. One is to help students better communicate, key takeaway messages about their energy-related research to a broad technical audience, and then two is to showcase some of the cutting-edge energy research that students are conducting right here on campus. So over the summer, we had 14 Stanford students give talks, and then a judging panel selected the top four. And we'll hear from them today. Before introducing them, let me just first thank the organizers of this program. Yufei Yang was the Seminar Manager. And she was helped by a number of student representatives. And then we have Maxine Leng, who has been doing this for all 11 years. And she helped coordinate everything. And as usual, everything went very smoothly. And then the judging panel was Steve Eglash, Jenny Milne, Michael McKayla, who joined me. So let me now go ahead and introduce all four presenters. They'll each give their talks one after another. And since one has a sort of tight schedule, we'll hold off on the Q&A until after the last talk. And then you can address questions to all four speakers. So our first speaker will be Peter Chanika, who is a six-year PhD student in material science, working with Professor Will Chu. His work focuses on understanding the atomic and electronic structure, the positive electrode materials for the lithium-ion batteries. And next up, we'll have Emily Lacroix, who is a fifth-year PhD candidate in Earth System Science. She's advised by Professor Scott Fendorf. And the results of her research should help inform land management decisions to increase soil carbon storage. Then we'll have Julian Bihill. He's a fourth-year PhD candidate in chemical engineering, working with Professor Hema Karunadasa and with Mike Tony. His research focuses on halide prop skyte semiconductors that could lead to more energy efficient writing and solar energy conversion applications. And then last but not least is Lily Buchler, who's a fifth-year PhD candidate in mechanical engineering. She's advised by Professor Van Root-Jagapal. Her research interests include data-driven control, optimization, and simulation in different power system applications. So without further ado, I'll ask Peter to give the first talk. Hello, everyone, and thanks for the introduction. I hope we can live up to these lofty expectations. But anyway, so my name is Peter. And today, I'm going to talk to you about battery degradation through cycling-induced oxygen release. So first, I wanted to introduce how a battery actually works. So in general, a battery consists of a mobile ion, in our case lithium, which will be shuttled back and forth between a low-energy reservoir and a high-energy reservoir. And in general, the amount of energy that we can extract from this battery is the product of two different things. The first is the capacity, which refers to the number of lithium ions, which will move back and forth in a given cycle. And the second is the voltage. And this is related to the energy that we can extract per lithium ion that moves. Now in my talk today, I'm only going to focus on one component of this battery, which is the positive electrode. And if we take a look at what the structure of the positive electrode material that I've been working with looks like, you'll see that this is a layered structure with layers of oxygen, lithium, and transition metals. And you'll notice that some of the transition metals are replaced with lithium atoms. And this is why it's known as a lithium rich positive electrode. Now one property of this material that I'm going to focus on today is the transition metal oxidation state, or the average transition metal oxidation state. So we can see here that for this material, it's about 3.4 plus. But once we charge the material, we have to remove lithium from the structure. And then the situation becomes a little bit different. The structure now will look something like this. And there are many things that change once we remove such a dramatic amount of lithium from the structure. But again, I want to focus for now on the transition metal oxidation state, which has now been pushed significantly higher to about 4.6 plus. In general, this can be a good thing. Higher oxidation states do tend to give higher voltages for batteries. So this would enable us to extract more energy. But they also have a potential disadvantage as well. So you might imagine that there's no guarantee that this structure is still going to be stable once we've removed such a large amount of lithium from it. And in doing so, we've gotten such a high transition metal oxidation state. And so the degradation I'll be talking about today has to do with oxygen release, which can lower that transition metal oxidation state down to a more reasonable value. So if we take a look, or we know that this structure actually is not perfectly stable over time, if we look at the electrochemical performance. So here, what we're seeing is that as we cycle this battery over 250 cycles, the voltage on both charge and charge is going from bottom left to top right and discharge going from top left to bottom right, the voltage during both charge and discharge is decreasing over cycling. And what this means practically is that we have less energy that we're going to be able to extract from this battery time goes on as we continue to cycle. You'll also notice that the x-intercept is not changing that much. So the capacity, the number of lithium that are actually going in and out of the structure in a given cycle is actually almost constant. It only decreases by a couple percent or so over 250 cycles. And I'll come back to this point a little bit later. So the question that was really motivating us to start this research is to try to answer the question of what's causing the voltage to drop over time so that we can design strategies to prevent that voltage decay and enable the batteries to maintain a larger proportion of energy for if you're using an electric vehicle, you might want to use the same battery for 5, 8, 10 years. So we really need to keep a stable voltage for much longer than just 250 cycles. So as I've mentioned, I'm going to focus a lot today on the transition metal oxidation state. So how can we actually measure this? One way we can do this is with a technique known as X-ray absorption spectroscopy. And in this technique, we can come in with an X-ray of varying energy on our material. And if the energy of this X-ray is exactly equal to the energy difference between an occupied and unoccupied state, then the material can absorb that X-ray and promote an electron to a higher energy state. We can then change the energy of the incoming X-ray and record how many are absorbed as a function of energy. And in doing so, we can get an X-ray absorption spectrum. Now as it turns out, the X-ray absorption spectrum is highly sensitive to the transition metal oxidation state. And we can see that here for several manganese-based reference compounds with different manganese oxidation states. So in general, we can see from the graph on the right that as the oxidation state increases or goes higher, then we have a higher absorption energy in the X-ray absorption spectrum. And this is basically due to the fact that the core electrons are held on to more tightly if you have a higher oxidation state. So what happens if we look at our own material? So if we look at our own material as a function of cycle number, we can sort of see the opposite happening. So we have the pristine material in black there. And then as we continue to cycle it, it's actually shifting to lower energy, indicating that the oxidation state of the transition metal is dropping. So here this is for manganese, meaning we're exciting from a manganese 1S orbital. But the same thing happens if we look at the cobalt spectra. So there are three transition metals in this compound, manganese, cobalt, and nickel. And nickel is about the same. This is just due to the particular electronic structure of this material, which I won't get into today. But in general, we can see that the average transition metal oxidation state is dropping. Often in these materials, oxidation state changes are associated with changes in the lithium content. But we have measured the lithium content of these materials directly, overcycling. And you'll notice that first, there's not much of a change in the lithium content. But secondly, it's actually going in the wrong direction to explain the spectroscopic changes that we see. Usually a decrease in lithium would be associated with an oxidation or increase of the transition metal oxidation state. But here we're seeing a small drop in lithium content and also a drop in the oxidation state. So we believe that this is not due to change in lithium content, but it's actually due to oxygen, which has been released from the material very, very slowly over hundreds and hundreds of cycles. And this gives us a good explanation for why the voltage is dropping as well, because lower oxidation states of the transition metals are associated with lower voltages for the battery. So to dig a little bit more deeply into this phenomenon in order to really develop strategies to prevent it from happening, the next thing I'll talk about is using the same principle of X-ray absorption spectroscopy, but now adding microscopy into the picture. So here are some results from a technique known as X-ray tycography, which I won't be talking about today. And what you can see is that now we've spatially resolved the transition metal oxidation state within individual particles from this material. So in the pristine material on the left, we have nearly a four plus oxidation state everywhere, except for maybe right at the very surface. But after even just 125 cycles, we have a significant amount of transition metal reduction even inside the bulk of these particles, even 100 nanometers or so from the surface. And we can see that even more clearly if we condense all this data into the plot on the left. So this means that this oxygen originating in the bulk of the particles does eventually get released over hundreds and hundreds of electrochemical cycles. So with this spectroscopy results in mind, and given that we found the material to be still a single phase, there are basically two potential atomic structures that could explain this. The first is this oxygen vacancy structure. This is the same as the pristine material, but now we've just simply removed some of the oxygen atoms and replaced them with vacancies. Another possibility is this densified structure. And this forms by losing oxygen and lithium kind of simultaneously and getting a structure with a higher transition metal content. Both of these can explain the drop in transition metal oxidation state. But the biggest difference is really the lithium content, because you do have to lose such a large amount of lithium to form this densified structure. And as you may remember, so we did measure the lithium content directly. And also electrochemically, we saw that the capacity or the number of lithium moving in and out was nearly the same over cycling. And so we're able to conclude from this that the oxygen vacancy structure is dominant. And so basically what's happening over many cycles is that oxygen is diffusing very slowly from the bulk with a kind of vacancy diffusion mechanism and eventually gets released at the surface. So just to briefly mention some possible mitigation strategies for this. So if we think about our oxide particle, there are a few different areas that we can look at to try to prevent this. Kind of the most common thing that people have looked at is coating the material with something that would block oxygen but still allow lithium through. This turns out to be pretty difficult. We have obtained some coating materials from collaborators that seem to show the same amount of oxygen loss eventually. So it's a challenging problem, but I do think it's potentially possible to do this. Since oxygen release is generally triggered by these very high transition metal oxidation states, you can imagine having a lower oxidation state right at the surface where the process kind of starts as a potential way to prevent this. And then finally, you can imagine if we can lower the oxygen diffusivity within the bulk, then that's another possibility as well. And one way to potentially do this is by stopping cation disordering. This has been suggested in sodium layered materials and you can ask more about this in the Q&A if you're interested. So to sort of wrap up here, the main conclusions are that oxygen leaves the bulk material during cycling and this results in the presence of oxygen vacancies and therefore preventing this bulk diffusion and release of oxygen is gonna be very important for stabilizing the voltage over hundreds of cycles. And with that, I'd like to acknowledge my research group which is Will Choose Group in Material Science. This is also a collaborative effort with people at both Slack and Lawrence Berkeley National Lab as well as Samsung. So thank you. So hi, I'm Emily LaCroix. Thanks again for being here and I'm really excited to talk to you about my work, studying soils as a form of soil carbon storage. So soils are actually the largest fast cycling carbon pool. They store over 2,300 gigatons of carbon which is more carbon than all of the plants on earth in the atmosphere combined. And the size of the soil carbon pool is regulated by inputs and outputs. So the main input to soil carbon is actually plants. So plants bring in carbon dioxide through photosynthesis to build their plant parts and those plant parts eventually end up in the soil. And then balancing those inputs, we have microbial respiration. So there's microorganisms living in the soil that use the soil carbon to drive energy during respiration and that releases carbon dioxide. So in thinking about these balance of inputs and outputs, you could imagine if the inputs to soil carbon were greater than the outputs, soils can act as a carbon sink. And this seems like a really amazing strategy for mitigating climate change, except there's one big caveat, which is that the controls on carbon dioxide emissions from soils are really poorly understood. Getting more carbon into soils is pretty straightforward, grow more plants, but how do we know that that newly input carbon isn't just gonna be turned straight back into CO2? So this has been the subject of a lot of soil science research for multiple decades. And through that research, we know that one of the primary controls on this soil carbon outputs are the role of minerals. So in soils, you have mineral surfaces and carbon can become adsorbed to the mineral surfaces and it's essentially unavailable for microbial respiration. You might be thinking we could just change the minerals of all the soil on earth, it's not really practical. So first, minerals have a finite surface area, so there's only so much carbon that can stick to minerals. And secondly, it's just really impractical to change the mineral composition of a soil. And so this leaves us with this really big question, which is how do we manage agricultural soils to be carbon sinks? And you might notice I skipped straight to agricultural, it's because in the contiguous United States, over 50% of the land is classified as crop or range land, meaning that there's already the infrastructure in place to monitor and manage these soils. So it's a good place to start for natural climate solutions. And this brings me to the topic of our group's work, which is anoxic microsites and their potential as a mechanism for soil carbon storage. An anoxic microsite is just a non-majority soil volume in which oxygen supply is slower than microbial demand for oxygen. So in other words, in an otherwise well aerated soil, you'll have these pockets where there's strong oxygen demand for microbes and oxygen diffusion can't keep up with that demand. So you're left with a pocket that's without oxygen and those pockets are called microsites. And so within anoxic microsites, microbial respiration of soil carbon is slowed by approximately 90% on a per volume basis. They can serve as trace sources of nitrous oxide and methane to the atmosphere, so it's not totally clear cut. And perhaps most pertinently, they're still really poorly understood and thus represent a really big opportunity but also a vulnerability for soil carbon storage. And so the goal of our group's work is to determine the contribution of anoxic microsites to soil carbon storage across different soil properties and management practices. And today I'm just gonna talk to you about a study that looks at the influence of texture and also climate, or in this case, moisture on anoxic microsites. And before I dive in, I needed to put in a quick soil physics lecture which is that soil oxygen supply is slower and fine textured in wet soils. So in the left panel, you can see for texture, if you imagine that an oxygen molecule needs to diffuse a net distance. In a finer textured soil, the diffusion path length is a lot longer. So oxygen supply tends to be hampered or inhibited in fine textured soils. In terms of moisture, oxygen diffuses 10,000 times more slowly through water than it does through gas or air filled pore space. So whenever oxygen encounters a water filled pore or is trying to diffuse into a waterlogged soil, there's gonna be really poor oxygen supply. And so because of these paradigms, we hypothesize that the contribution of anoxic microsites to soil carbon storage would be greatest and finer in wetter soils. To test this hypothesis, we actually collected soils from the Stanford dish. So we collected soils from three different textures along a hill slope. And we applied two different moisture treatments to the course. To measure the contribution of anoxic microsites to soil carbon storage, we've relied really heavily on this framework, which is this idea that if a soil has anoxic microsites that are contributing to soil carbon storage, if you were all of a sudden to aerate that soil, there should be some sort of increase in the steady state CO2-F flux after that aeration event. And that increase in CO2-F flux should be commensurate a representative of the carbon stabilized by anoxic microsites. And so we applied two different aeration treatments in the lab. The first was we incubated soils under a regular atmosphere. So like the air we breathe, which is 21% oxygen. And then another subset we incubated under a 32% oxygen atmosphere. And what we found was that the extra oxygen actually increased CO2 emissions from sandy loam soils, which are the coarsest soils that we sampled. And to orient you a bit on this plot, because we'll see a similar one to it, each panel represents a different texture of soil. So finest is on the left and coarsest is on the right. The X positions are moisture. And then the black bar is gonna represent kind of the control CO2-F flux from the soil. And the red bar will represent the CO2-F flux from the more oxygenated treatment. And so you can see there's not really a big difference between the black and red bars, except for in the sandy loam soil. And the effect seems to be a little bit more pronounced in the wetter treatment. The second aeration technique that we applied was physical disturbance. So we took a soil and we disaggregated it. So we broke it out of its core, put it through a sieve and spread it in a broad area pan to aerate it as best we could. And this is also meant to sort of simulate tillage, which is very regular practice in croplands. And what we found was that physical disturbance increased CO2 emissions from both the loam and the sandy loam soils, but there was no effect in the finest textured soil. The effect seems to be a little bit greater in the wetter soils, but we need more replicates to be sure about the influence of moisture. So to revisit our hypothesis, which was anoxic microsites would matter most in the finest soils, we weren't right. So our hypothesis is wrong. And this has sort of led us to a new evolving hypothesis, which is the role of microbial oxygen demand. So if you think back to three minutes ago when I taught you about mineral protection, if you imagine a fine textured soil versus a coarse textured soil, a fine soil has a lot more surface area of minerals for carbon to stick to. And then a coarse soil on the other hand has a lot less mineral surface area. So as a result in the coarser soils, a greater proportion of the carbon is free and available for microbial respiration. And so as microbes are trying to respire that carbon aerobically, it creates a big demand for oxygen. And so our thought is maybe the oxygen demand is actually driving the formation of the anoxic microsites. And so diffusion just can't keep up with that microbial demand. And so some conclusions from this work. Anoxic microsites may be most useful for leveraging carbon storage in soils with low mineral protection capacity, so coarse soils. A disturbance should be avoided in sandy soils to maximize soil carbon storage. And our next steps are to apply this methodology across the US corn and cotton belts. So I spent this past summer sampling at a few long-term tillage experiments across the US and I can talk about that more in the Q and A. And with that, I want to thank all my funding sources and my wonderful lab group and the energy seminar for hosting us today. Thank you. My name is Julian and I am in the chemical engineering and chemistry departments and I'm going to talk today about our work on understanding and trying to manipulate some of the defects that we see in halide perovskite semiconductors. And this is where I'm very glad I'm following Peter because he gave a great introduction of electronic structure and defects. The materials that we're interested in, in particular, are semiconductors and these really fall somewhere between metals and insulators in terms of electronic structure. So we can think about the occupied states and unoccupied states of material relative to energy. So a semiconductor will have something that has somewhat of an intermediate band gap between these two and will have some interesting optical and usually electronic properties as well. So we can imagine now in the energy landscape where these type of materials come in are in a few different places. The one that we probably all know very well is in photovoltaic devices. So in this case, we want to absorb a lot of photons from the sun and then we'll try and separate the electron in the hole to get some electrical power from our device. So here we want to have a low band gap, absorb a lot of light and then separate our carriers. You can also imagine basically the exact opposite situation where we provide energy to overcome the band gap energy and then what we really want to do is collect this light that comes out or tune the properties and tune the emission from the material. So here we'll have a high band gap energy and then focus on the emission properties of our material. But to go back to solar absorbers, that's really kind of what we'll focus on today in terms of the materials and the applications. This is the architecture of a very efficient silicon solar cell. And if we zoom in in particular on the absorber layer, so this is the silicon, you might imagine this perfect silicon lattice where we have the same atomic structure extending in all three dimensions. However, we can have defects that occur in these materials. So if we now substitute one of the silicon atoms for titanium, we can really, really greatly affect the efficiency of the solar cell. So this can reduce the efficiency by more than 50%, even at super low concentrations. So considering the defects in these materials that are usually thought to be perfect is very important for real world applications. And so now where we come in, we study these halide perovskite semiconductors, which is this crystal structure here where you have these metal halide octahetra extending in three dimensions. And really they're very old materials. So you can see they've been studied since the 1890s, but not really implemented into solar cells and optoelectronic devices until about 2010. So you can see now, there's a lot of excitement about these materials because it really just gained a lot of efficiency in the last 10 years essentially. So now we're trying to understand a little bit better what makes these materials work, what makes them degrade a lot of different aspects. So one benefit is that they're very easy to synthesize, so we can make them near room temperature and we can also manufacture them into thin films for devices very easily. But one of the downsides to the fact that they're easy to make, they're also very easy to degrade. So we can imagine now, if I take a slice out of the crystal structure and we look at an atom here that's missing, this is a vacancy, just like we discussed before in the battery materials, now you can get free movement of the halide through the material. And so this can actually be a bad thing. So you can imagine degradation processes and other polarization things that occur in devices based on the fact that you have all these ions moving around. And this is now where we come in, we're in organic chemists. So we tend to study the bulk properties of these crystals. And my two colleagues, Adam and Nate, we're among the first to discover some of these defect reactions and then characterize a lot about the thermodynamics and the transport of these vacancies through materials. So now this is a double perovskite crystal. So we have two metals rather than one, but it's the same structure. And actually if you just leave a crystal like this out to sit, it will lose bromine over time. So it's a bromide crystal, you're losing the bromide gas. And that actually contributes to the electronic structure. So we see two electrons go in and then we can see the conductivity increasing significantly over time. And then what's cool is that you can now expose it to bromine and it will go back to the initial state. So we know now that this is an equilibrium where we have the perfect bromide lattice, which is an equilibrium with a vacancy, the halogen gas and two electrons. So we can manipulate this equilibrium essentially. And now where I came in, we've been studying this other material which has a very similar structure, cesium-104 iodide. We can grow these large beautiful crystals as you can see in the image there. And we've been studying a lot their conductivity and some scattering methods to characterize the structure as well. And we essentially see the same type of behavior where the conductivity is increasing over time, which is indicative of this halogen exchange reaction. And one thing you'll notice is that the shape of this curve is really nice compared to the last crystal and it actually gives us an indication that there's a diffusion limited process going on. And so we've gone into the detail now of this material and the transport properties. So we can repeat this measurement at three different temperatures or even more different temperatures. And we can apply a diffusion model to it as well. So we're modeling the movement of the vacancy from the surface of the crystal into the bulk of the crystal. And what we get out of that are some kinetic parameters so we can now understand what the diffusion coefficient is, how fast the vacancy is moving through the crystal. And also the activation energy. So actually how much energy it takes to migrate the vacancy through the crystal. So now my PhD has actually focused a lot on seeing these defects and really understanding the structure as well as the electronic structure. And so we can have a real space model of what this material looks like with these metal halide octahedral, like I mentioned. And then if you imagine doing an x-ray scattering measurement, so you take a crystal and you hit it with x-rays, what do you expect to see in the x-ray scattering pattern, the diffraction profile? So you can see with a perfect material, you see a perfectly spherical symmetric Bragg peak. However, if you start to generate a lot of defects in the material, now you have strained fields in the material and this will give rise to some asymmetry in your diffraction peak. So now we can see the shape is changing and all arbitrarily just adds more defects here. And we can see that in the extreme case where we have a lot of defects, now we have a very different profile in our x-ray scattering profile. So now I can go look at this in the lab and see if we can characterize this type of behavior. So we've done that a little bit. We've started to get some initial measurements. One of those that we can do in real space is to actually image this using electron microscopy. So now we're looking in real space at the structure and if we can push down to the atomic resolution, we should be able to see some of these vacancies in defects forming. And then also doing the x-ray scattering measurement. So this is what I was talking about in terms of the simulated patterns. We can start to see initial results that show this asymmetry in the x-ray scattering profile which gives us some indication that there are defects in the structure. So now we've characterized in the Heli double perovskites pretty extensively that there's this defect reaction occurring. But of course we also wanna motivate some changes that we can make to the crystal structure that could potentially disfavor this reaction or stabilize the material in a device. One of those ways is by doping. So actually on purpose implementing some dopants or defects into the material that will actually offset the effect that we see. So really what we wanna see is this electron concentration just a flat line with respect to the x-axis here. However, we see this very slopey line that's basically following the vacancy concentration. So this is not good. However, if we incorporate some two plus dopant into the material at a higher concentration now we can somewhat fix or stabilize the material. So now we see a flatter line with respect to that electron concentration. And then going even further beyond the double perovskites we really wanna show in some of these lead halides that actually show up in high efficiency devices that the same kind of occurring the same kind of process could be occurring. So establish how general this halogen exchange reaction is across the whole family of materials. So with that I'll just wrap up by summarizing to say that we really characterized this halogen exchange mechanism pretty extensively. And we think that we need to have some sort of atomic level or chemical solution at the local level that will disfavor this reaction in order to really stabilize the device and then the module because you can think about encapsulants and some other techniques but really we're talking about very small molecules at the atomic scale. So we think with the chemical solution or atomic level solution we can really stabilize these materials. And with that I'll just wrap up by thanking my advisors, Hema and Mike, the three folks who are most involved in this work with me all the group members, funding sources and some of the collaborators on the structural measurements. Thank you. All right, great. Hi everyone, my name is Lily Buchler and I'm gonna be talking about my work on learning accelerated power flow simulations. So I wanna first motivate this work by talking about how the power grid works and how it's changing. So traditionally power systems have been centralized with power generated by large scale power plants. And that power is distributed to consumers through transmission and distribution systems. But as the costs of renewables and energy storage fall we're seeing more and more of those resources installed both at the utility scale and as distributed energy resources in both residential and commercial applications. And so as these changes occur where utilities are going to need more and more need better tools to analyze how these changes affect their system, right? So one of the main analytical tools that we use is called power flow simulation. Power flow simulation essentially allows us to analyze how power generation and demand affects voltages in a network. So voltages are important because most appliances and equipment are rated to operate at a specific voltage level. So for example in your home, most of your appliances are rated to operate at either 120 or 240 volts. And so utilities use control systems in order to make sure those voltages are close to those nominal levels. And so power flow simulation essentially allows us to model this relationship between power and voltage. Normally we think about power in terms of its real and reactive components, the P and Q. And we talk about voltage in terms of its magnitude and phase angle, V and theta. So mathematically, power flow simulation involves solving the so-called power flow equations. The power flow equations are a nonlinear system of equations where power is defined explicitly in terms of voltage. But normally for simulation, we actually want the opposite mapping. We have the power injections at most of the nodes in a system and we wanna calculate voltage. But because of how these equations are structured, we can't analytically invert them. And so we have to use iterative numerical methods in order to solve them. And so these numerical methods like Newton-Raphson or fixed point iteration have been applied to this problem for many, many decades and have been highly studied and optimized. And for a single calculation, they are very efficient. But normally for analysis, we want to do these types of calculations as part of a time series simulation that involves lots and lots of power flow calculations. So at each time step, for example, we have some inputs to our power flow problem. We use a power flow solver, which is a numerical method in order to solve that system of equations and we get a solution. And we repeat this for every time step. And so this type of setup is often called quasi-static power flow simulation and is one particular flavor of power flow simulation and is often used for steady state type analysis. So that's things that happen at the time scale of say minutes to hours. And so there's a variety of different available simulators out there that do this type of analysis. And you can imagine if you, for example, have a really long time horizon or you want to model uncertainty in some variable in your system and need to run a lot of simulations, you have to do a lot of power flow calculations and that can be computationally expensive. So there's a variety of ways to speed up these calculations. For example, people often try to decouple the system of equations or use sparse methods for matrix decomposition. And those are used pretty heavily in this research field. Another way is to simplify the power flow equations by, for example, using a linear model, which is easier to solve. A more recent approach is to use machine learning to try to do faster simulation. So for example, you can run a power flow solver for a certain number of time steps, train a model to predict the solution from the inputs and use that to completely bypass the traditional power flow solver. This speeds up simulation because generally use evaluating an explicit function is much faster than running a numerical method. And so this has been a really hot topic the last couple of years in this research space. And there's been lots of papers looking at what specific form this data for mapping should take and has been shown to speed up simulations considerably. But there's a number of challenges when it comes to actually implementing these methods in the types of simulators that utilities actually use. So one challenge is that previous studies often make a lot of simplifying assumptions about the power flow, which makes it pretty much impossible to plug these methods into the simulators that utilities actually use. Another challenge is about generalizability. So a lot of these data-driven models are trained offline on datasets and then you assume that training data and testing data come from the same distribution and that you can just apply it to a test set. But often that's not the case because loading conditions can change, network topology can change and that assumption doesn't always hold. Another challenge is computation time of some of these data-driven methods. So often some of these, for example, deep learning based methods, they're very accurate. You can get very fast predictions but training them takes a lot of time and that can outweigh any costs, any benefits from doing fast prediction. And finally, we found that the accuracy of a lot of these methods highly depends on hyperparameter tuning, which means they're not really as robust and applicable for use for people who don't have an ML background. So in our work, we developed a different approach that tries to address some of these challenges and we implemented it in the GridLab D Power Flow Simulation Engine, which is a popular tool used by a lot of utilities and national lab researchers. So instead of completely trying to replace the Power Flow Solver with an ML model, we use ML to kind of augment or accelerate the solver. So instead of training data-driven model offline to predict the Power Flow solution, we actually update it online during the simulation and that way it can adapt to changing input conditions and helps with generalizability. We also selectively decide when we want to use our approximation and when to fall back on the traditional Power Flow solver. And so this approach works best when the inputs to the Power Flow problem don't change that considerably from one time step to another and we're able to avoid doing redundant computations and also learn from previous solutions to inform our prediction. So this framework both speeds up simulation by avoid using the more computationally expensive Power Flow solver as much as possible and also by seeding the Power Flow solver with an approximate data-driven solution so that it converges more quickly. And so we implemented this approach in the GridLabD simulation engine and tested it on a variety of distribution systems and GridLabD uses what's called Newton-Raphson-based method that's based on the current injection method. It's one standard type of Power Flow solver and it uses sparse methods for matrix decomposition so it's already fairly fast. But with our current implementation, we're seeing a speed of about three to five times the fastest that that numerical method can do and with a faster implementation, with a better implementation, we think that will be around five to eight times faster. So but with those computational benefits, there is a trade-off with accuracy but the errors that we've observed are on the order of one E minus five to one E minus three per unit voltage which is still very acceptable for a lot of applications. So kind of in conclusion, we found that combining more traditional simulation methods with data-driven prediction is a promising approach for speeding up Power Flow simulations and in the future, we have more and more controllable resources in our power systems and a more distributed Grid, it will be more, it will be increasingly important to have tools to do both accurate and fast simulations. So we plan to release this code open source as part of the Slack version of Grid Lab D in the future so that it's accessible to both researchers and utilities who utilize these tools. So finally, I'd like to acknowledge my collaborators, David Chassan at Slack, my advisor professor, Ron Rajagopal and Audie Tom and Siobhan who are other students who've worked on this project as well as the California Energy Commission for funding this work. And thanks for your attention and happy to answer any questions later on. Wow, those are four incredible talks. I find myself kind of daydreaming in five years while I see this person receiving an award, maybe a Nobel Prize type work or we're at Stanford, will they or their students do a startup that starts as a small company and then becomes the next Google. I think it's actually quite possible. So we do have a few minutes for questions. Anybody, actually I should say Marlies, our CA has put the attendance sheets right outside the back and the front door. So please sign them, not the guest speakers but the students registered in the class. So any questions? I'm sure we have some aspiring technologists in the audience. Richard, you wanna ask one? I could ask one or vaccine just to get them all away. These are all four excellent talks. And I think maybe to Julian I'll ask a question. And that is, you left us hanging a bit. You told us the mechanism but now what's the ways in which you can, you can, what you see in the future is your work to try and address the issue of this. Thank you Richard. Yeah, thanks Richard for the question. So this kind of relates I think to the fact that we've now characterized the instability quite well but maybe don't have the answers in terms of stabilizing the structure in all cases. But the dopant I think is the best strategy that we can come up with so far and one that we're actively pursuing to stabilize the material. So this is kind of what I discussed before where we have an electron concentration that's moving around quite a bit in the left panel of this figure. And then if we incorporate a dopant because it's also positively charged, that's the key thing. The vacancy is a positively charged defect and so what we wanna do is dope with a two plus metal to replace the one plus metal in the structure. We think that that will, if we get it in at high enough concentration to replace the original one plus metal that it will stabilize that electron concentration and that's really the key thing towards stabilizing the material in a device stack for example. So I think the compositional tuning in the dopant engineering is the best way. Thank you. Thank you. My question is for Lily. I'm curious if you also measured the amount of cost improvement there was in addition to the speed improvement and a follow-up question on that is where do you see some of the biggest applications? Do you think this will kind of be used in energy trading or like where do you think these, yeah. Yeah, so by cost do you mean like money cost or, yeah, so often we talk about cost using a different tool that's called Optimal Power Flow which is a little bit different than Power Flow. It's the tool that we use to dispatch resources and power systems. And so in that type of tool we think about cost in terms of what resources should we dispatch to minimize cost. So that's also another tool where ML has been used to accelerate analysis. So in Power Flow simulation we don't really think about cost directly. You can derive cost from it. But it's not necessarily as relevant. And sorry, what was your second question? Yeah, so where Power Flow simulation is most computationally expensive is for large systems and for distribution systems. So for transmission systems you can frequently make simplifications to the Power Flow equations which for example make them linear and much faster to solve. In distribution systems you normally have to use a more complicated model and you have to use these numerical methods to solve them. So it's really distribution systems with a lot of resources, for example, a lot of controllable DERs, energy storage, people have in their homes where it's gonna be more useful and we're gonna see that increasingly in the future. I had a question for Julian. I was wondering if you could put into a bit more context how stability is important here. Is there some industry standard that you're shooting for? Are there some, I don't know, year long tests that you can do on a perovskite photovoltaic to determine some final metric? Thank you for the question, yeah. So like I mentioned we are pretty fundamental in organic chemists so we don't make devices ourselves but we certainly talk with a lot of folks who study devices and worry a lot more about the stability but I think a good place to start to discuss this is probably looking at the efficiency scales. So these efficiencies are for very small solar cells and typically not stable enough to be actually implemented into a module or something larger than that. And so there are definitely industry standards and certain accelerated degradation tests that folks can do on devices. But yeah, so far we haven't actually gone into the device world yet personally but we focus on the crystals and then try and basically derive as many insights as we can about the fundamental structure to kind of collaborate with people who actually make devices. But in general I think the key aspect in terms of the stability more broadly speaking is just the fact that you have a lot of these low energy processes happening in the crystal so you can move ions through very low activation barriers. And like I mentioned that gives rise to a lot of degradation and some basic polarization meaning you can apply a potential to your device and the internal gradient of ions will actually oppose that field. So there are a lot of unnecessary undesirable effects that will occur and we kind of collaborate more so than do the device engineering ourselves. So I have a question for Lily. As wondering sort of you mentioned the robustness is sort of a big problem, right? Traditional deep learning methods. How does sort of accelerated learning help with that? Is it that it's a pretty small time scales or you sort of just using areas where you're stable but so that's not a problem. So I missed the first part of your question. Just about how does the accelerated learning methodology like enhance the robustness compared to traditional deep learning methods? Oh yeah, so I think the biggest difference between our method and previous methods is training offline versus training online. When you train offline, you basically need to predict what your distribution of data you're gonna see online and that can be hard to do. If you have a distribution system with tens of thousands of nodes and switches where the topology can change, you don't know what topology states are gonna see pre-simulation and so it's kind of intractable to be able to train a reliable model offline. And so for our approach, we basically, we train a model online and assume that you're simulating at a fast enough resolution so that your state doesn't change a whole lot from one time step to another and if it does, you just fall back on the traditional solver and accumulate enough solutions until you do have a good model. So by kind of putting the learning in the loop with the traditional solver, instead of just like by itself adds more robustness. I had a question for the third presenter. Just with the map that you showed with the different sites that you're gonna go to for the soil samples throughout the US where there are certain factors that influence your particular decisions for specific sites and if so, like what were those factors? Yes, that's a great question. They're really glamorous locations. So we did have some reasoning behind our choices. So the first was that it's a partnership with Soil Health Institute. So they have a series of site partners that they already have an existing project with that we had a big list of sites to choose from. And then from there, we were really interested in five key variables. So climate, texture, tillage, mineralogy. So I guess that's four, but climate is moisture and temperature. And so we looked for sites that spanned essentially a gradient in each of those variables. So we ended up with a matrix of sites where we could compare three sites from three different temperatures or three different precipitation regimes. Yeah, does that answer your question? Yeah, thank you. Thank you all for presenting. That was a really interesting and fascinating presentations. I had a question about battery cycling time from the beginning. So absence of any change, what should we do to optimize our battery life if you own an electric vehicle or even a laptop or a cell phone? What's kind of like best practices for that? Right, yeah, thanks for the question. So I guess there's maybe a couple of things I'll say for this. One is that the particular material we were looking at is sort of like a next generation kind of material. So that is one that is potentially cheaper and could have higher energy density, but it's not currently in use. It's actually not totally clear like how much of this oxygen release, like slow diffusion is a problem in the materials people use today. I think personally, I think it is a little bit of a problem, but most people think it's not. So I don't know, we'll see. But yeah, I guess one thing that is kind of interesting is that like the battery in your phone, for example, typically the more you charge a battery, the kind of worse it gets. So you can, in terms of stability, you can sort of think of this like, like a battery is sort of like, I don't know, when you charge it, you're like pumping water up a hill or something like that. So you're always creating something that's like less stable when you charge it. And then when you discharge you're going back to something more stable. So in general, you kind of wanna stay at like low states of charge. But that being said, like your phone manufacturer kind of limits you. It doesn't let you charge high enough to the point where like things start to get really bad. So they're kind of like trying to fix that already, but I guess in general, there's always sort of a trade-off between like how far you charge the battery and how much energy you can get out of it and then how long it lasts. So even using the same material, you can make the battery last longer if you just don't charge it as much, but then you get less energy. So they sort of, the company's already sort of, they have some calculation for whatever, how far they'll let you charge it. Yeah. My professor one time was kind of joking that like Apple or something, they should give you like an emergency button on your phone that if you're like, you really need it and it's out of power that just lets you like completely destroy the battery, but use it for another 10 minutes. In theory, like that could work. So I don't know. That's an idea. Anyway, yeah. Great. Unfortunately, I think we're just about out of time. So I'd like to sincerely thank Peter, Emily, Julian and Lily for excellent and very inspiring presentations. Richard for coordination and all of you for great questions. Thanks very much.


Hello, hello, hello. My name is Matthew Coast. Is that weird? My name is Matthew Coast. And welcome to this pressing question that we have today, which is if will a man use a woman if he's allowed to? And so this is a question that came to me from our community not too long ago where a woman actually mentioned that she thinks that if you let a man that he will use you, right? And I think what she was implying was that he will use you for sex. Now, the question is, is this true? Is it true? And I think it depends, right? It depends on the man. Anytime I hear kind of this thing where men or women say most men or all men or men say all women or most women, it's a little cringy for me to be honest because the question is, how often does it happen? And I think that the answer is a little bit complicated. And so we need to talk about a few different things in regards to why somebody will use another person. That way you can figure out if a man is trying to use you or not. And so a lot of people think that men are just going to use them in some kind of malicious or have some kind of negative intent with this kind of using a person type of thing. But I think what really happens with both men and women is that we get into these different situations where we experience good emotions, right? We feel really good. We have something that's going on that feels good to us. And so what we do is we want to continue experiencing that. Because men and women are obviously different in some ways. We're also the same in many ways. And we're actually going to be talking about a bunch of different ways that men and women use each other today so that we can kind of get a more of a sense of what's going on here. Our channel and what we talk about on here is this idea of partnership, right? Being on the same side, having compassion for each other. Making sure that when you're in a relationship that it's valuable and beneficial to both of you. So real quick, I just want to say hello to everyone. If you're here and watching right now, hello. Say hello in the chat. Rose says hello. Amy says hello. Donna says hello. So say hello if you're in the chat here with me. And tell me what you think. If will most men use women if they're allowed to? What do you think? So Levine says hello. Princess Mamazilla Dragon Writers says hello. It's a great, great name. Shane, hey Liz, hey. Myrion, hey. Sunny days, hey. Suna, Suzy, Evan, Kim, Colleen, Lisa. Wow, we have a lot of people saying hello right now. So the question is will most men take advantage of women if they're allowed to? And so, and like I said, it depends. It depends on the situation. I think that most people will actually take advantage of other people, not in like a way where they wanna hurt the other person, but they do it because they're consumed with themselves, we're all consumed with ourselves. The reason this question came up was actually because we're consumed with ourselves and we look at things and we think, oh, men are, a lot of the women in our community were like, oh, men are trying to use women. And the reality is that we're both trying to use each other and there's a better way, right? There's a better way where we're experiencing the great things that we're experiencing, we're getting our needs met, we're having joy and fun and pleasure and we're making sure that we're in good situations. And that's kind of what we really wanna focus on in this community and with what we do here, none of this stuff that we do is about revenge or hurting anybody.  That was a joke, you don't have to cry in a corner. Although sometimes it can be very powerful to go cry in a corner. So I'm not talking bad about crying in corners. Okay, so what do we have here? The answers are, yes, because it is a mural request via love language understood, mutual request. They will majority of the time, especially if his character is not stronger than his integrity. It's a good one, Liz. What do we have here? He can be kissing you like he means it while using you. Is that a question or a statement? Not in a mentally healthy way? Yes and no, depending on, I think there's another thing too that we need to consider here, right? What is using somebody? So I think what we would define as using somebody here would be, and I think the comment originally in our community was about sex, right?   They tend to fall in love. They tend to have that dopamine come out, the oxytocin come out, and they start feeling these so good feelings of love, love, love, love, love for this man that they're dating. And so they're like, why isn't he feeling the same way? And there's actually women who are in our community who have been seeing men in non-committed relationships for up to 17 years. Can you imagine this, 17 years in a relationship? That's not a commitment. There's no commitment. The guy doesn't even call her his girlfriend. I mean, it's crazy. It's crazy, but it happens. It happens all the time. I would say that that's a situation where the guy knows, right? A guy knows that she wants something more, but he's not letting her go and he's continuing to have this sexual relationship with her where he's getting all of his needs met, but she is not. I would say that that knowledge and knowing is what constitutes using somebody. So I think that if you're in a situation where you're both kind of sleeping with each other and it's fun, that's fine, as long as you know that it's just that, right? I think once as a woman, usually the longest period of time for most women from what studies I've read is that it takes somewhere between like three weeks and three months in order for her to start feeling those deep connected feelings with a man from having sex with him out, even with it not being a committed relationship. And usually after that period of time, the woman will definitively start feeling more and more connected with a man. And so if I were you, like, I was watching something earlier today. I've been kind of obsessed with watching Steve Harvey videos lately. It's kind of embarrassing, but he's got some really interesting things that he says. Some of the things that I think that he says is just totally off and some of the things that he says I think is really on. And one of the things that he said in one of the episodes I watched today was about how if you're in a relationship for three months for more than three months, you need to know where this relationship is going, right?  He has an idea of where things are going. And the question is do you fit into that picture of where he thinks he's going? And so before the three month mark, and I see kind of see what he's saying here where he's like, you know, before the three month mark, it's like, well, you know, you're kind of getting to know each other. You're still trying to figure each other out. You know, is this the person that I really want to have a committed relationship with and you know, get married to and all that kind of stuff. Honestly, I think you should be figuring this out beforehand. I, you know, I don't think there's anything wrong with having a conversation about this. If a man freaks out in a conversation like this, you already know what your answer is. Yeah, so that's true too. So Karen says a high value woman knows when to say no. That's true. And it will make a man feel like you're, like he recognizes your value if you can say no and if you can have boundaries. One of the things I talk about in my frame program, my Love Frames toolkit program is that whoever has the strongest frame, like the strongest beliefs about what's going on will win. So if you are like, hey, no, these are my boundaries and you're really strong about them, you'll win that. If you have beliefs about, you know, this is my value and these are the things that I accept and don't accept. Whoever's strongest in that kind of belief system will end up, will end up winning and will give that belief system to the other person in regards to the relationship.  I don't know if that was too complicated for everybody. Anyway, I just wanted to go over a few different ways that men and women kind of use each other. That way we can, that way you can make sure that you're not getting into a situation where you end up getting used. So Karen said, don't agree to a friend with benefit agreement. Arrangement, yeah, you know what, I agree. If you want something real, actually as a woman, I don't think you should ever really get into a friend with benefits type situation ever. Just because of this, a lot of women end up getting into situations like that because they're like, oh, well this guy seems really hot or whatever and they end up getting into a situation like that with a guy where they're just hooking up and then they start to feel things for him and he's not feeling it for them and it ends up hurting really, really badly. So yeah, so let's talk about some of the ways that men and women use each other. And these, this is a list that I came up with and what I ended up finding was that I created this list and I looked at it and I realized that all of them are mutual, right? So I know men and women that have experienced all of these, except for maybe one of them and we'll get to that though. So the first one is free food, free drinks. When I first think about this, I think about women kind of in bars, right? Like asking for free drinks from men which I have been a victim to. And when I was young, like 10 years, 15 years ago when I was going to bars and clubs and stuff in my early 20s, early mid 20s I had run-ins with this where women would come up and just get free drinks and walk up run-off which is kind of a funny thing to think about. And then men, but men do this as well, right? They do it less in terms of, they usually do it less in the initial stages. Women tend to do it more in the initial stages and men tend to do it more in the later stages or in the relationship stages where a guy will get, because the fastest way to a man's heart is obviously through his stomach. And so a lot of, if a man thinks that he can get free food from a woman and he has no intention with her that can be a situation that happens as well. I've seen it, I know people that have experienced that. So the second one, the second way that men and women use each other is through getting validation or making themselves feel better, right? Feel better about themselves, ego boost. And when I wrote this one, I was thinking about men getting kind of an ego boost from women, right? Because men and their egos a lot of times are, and it's actually both, especially in American culture these days, there's a lot of ego going on right now where men and women are, they just, they wanna feel good. They want that validation that they get from the opposite sex. And for women, this is like the Instagram thing, dancing in front of men, different types of situations like that. Sometimes for men, a lot of times it's like getting into a relationship or having a woman, that there's a woman in our community, not too long ago, or maybe this was on the last live stream. Anyway, there was a woman recently who mentioned that, oh no, it was in the community. There was a woman recently who mentioned that men, they've talked to some men, and those men were like, oh yeah, I want women to chase me. I want you to chase me.  And the question was about, you know, this guy wants me to chase him, should I chase him? Right, and my answer to that was, I don't know, do you want, if a man wants a harem of women who all chase after him, do you wanna be one of the harem?   Because investment is what creates a committed relationship and makes you feel like you want a committed relationship with someone. So the more that he invests in you, the more likely he will want a committed relationship with you, and it's the same with you and him. And so if you're investing and he's not, then you're probably going to be the one that wants the committed relationship and he won't. And so it's not always about what people like, right? Cause men will go for things that they like, right? Men will go for sex sometimes because they like it, not because it leads to something meaningful down the road. One of the challenges that we have a lot in our society is short-term thinking, short-term ego boost thinking type stuff. And so, yeah. Exchanges. Yeah, so, exactly, exactly. So I'm just reading some of these chats here. Yeah, absolutely. Yeah, some relations aren't anything but exchanges. It's true. Yeah. Yeah, I mean, if you're, I don't know why a lot of women, I've still been kind of searching for this answer for why women are constantly trying to change men. We get women in our community all the time that are trying to change men. And is that Harambe? Is that how you pronounce it? That's hysterical. That's the gorilla. And so it's one of those things where, yeah, it can be a challenge. Harambe, that's too bad. We're kicking you out, buddy. Sorry. Sorry, if you come in here and say inappropriate things, we're kicking you out. We don't tolerate this anymore. Yeah, well, sometimes, and I think it's human nature, right? Because we end up with these people in relationships. And we wish, you know, I think a lot of times what happens is we wish that things were a little bit different. Like we wish they were a different way. And I think that's a problem, right? I think wanting to change somebody is a problem. I went through this with my father, actually, for a while where I was trying to get him to eat a better diet because I wanted him to live longer. And trying to force him to eat a different diet just made our relationship fall apart. It didn't make him eat better or want to eat better. And I think that's pretty common with everybody when they're trying to change somebody is it doesn't really work. Changing people doesn't work. Accepting them for who they are and then deciding whether who they are is acceptable to you or not is what works. Setting up boundaries and saying this is who I am and this is what I need in order to feel valued and cared for and cherished in our relationship. I think that is a much more powerful way to do things. Yeah, okay. So Lynn says it works both ways. It does work both ways. All right, so we're moving on here. Number three. So the third way that people use each other is to make their lives seem better or normal to their friends in real life or on social media, sometimes to their family. So people will get into relationships just because they want to feel like they're valuable. They want to feel like they're worth being in a relationship with. And so a lot of times people, both men and women will get into relationships and just hang out in relationships that they don't particularly care about waiting for somebody better to come along because they want to feel like they're normal or okay or they want their friends and family and followers on social media to think that they're cool or whatever happens on both sides. So men and women do this. Another one is using people to run personal errands when they have no interest in the person. So I've seen a lot of women do this before where they, I've heard guys complain about it, where women will just use them to send them on errands and stuff with or without her and have absolutely no interest in the guy. I think some guys do this as well, right?  So if you are trying to show a man how valuable you are to him, that doesn't work. That never works. I know women that also try to convince men that they're valuable enough, that's another no-win strategy. So don't do that, don't do that. Don't run personal errands for men just to try to impress him or make him feel like you're valuable or whatever. That doesn't work. So another one is paying for things and we talked about this at the beginning with free drinks and free food but it's a little bit different because this is definitively a money strategy which in this works both ways as well. I know men and women that have been in situations where the person they were seeing was buying tons of things for them, gifts, taking them out to movies, buying tickets for concerts and all kinds of other things and the person that had no interest in really being with that person at all and they knew that person had interest in them and they just let it continue to happen because it felt good, right? And so this happens on both sides all the time. So don't get into a situation where you're constantly, you know, a lot of these things, what they, the reasons that they happen is because a woman doesn't feel like she's enough for a man and so what she ends up doing is all these different things, paying for things, running errands for a guy, right? You know, giving him stuff, free food to try to make her seem more valuable to him and it just, it just, none of that stuff works. Another situation is paying bills. So I've seen this, it's a big thing in the men's industry because of the whole gold digger thing, right? So guys are scared out of their minds of getting into situations where they have a gold digger who is just, you know, using him for his money but it happens in our community as well. There's women in our community right now who have been in situations where they were paying a man's bills for him, you know and not even living with him and paying his rent for him.  I don't think you should ever be doing that for a man. Just period, end of story. I don't think you should ever pay a man's bills, ever. He's a man, he needs to figure it out, right? If he needs to go and get a loan, if he needs to go and get another job, if he needs to figure some things out, let him figure things out. I don't think you should ever be paying his bills for him. That's that and so let's move, let's move to the next one. This is the one that I think might just be something that women use men for, which is the fixer, getting him to fix things for her. That's something that, you know, men are fixers, we're problem solvers, we like to do stuff like that and sometimes, but the next one is primarily a thing that happens to women, which is the one that we were talking about at the very, very beginning of this, which is sexual desires or sexual needs, getting those sexual needs met.  And that's a problem and so that does, but it happens both ways. I know plenty of men that have been in situations where, and it happens less often with men because it's easier for women to get sex anytime they want it, whereas for men, it's much, much more difficult. I think you'd be surprised, I think a lot of women would be surprised at how easy they could get sex if they just asked one of their guy friends if they wanted to have sex. I think you'd be very, very, very surprised. But for men, it tends to be a lot more difficult. And so what ends up happening is you see all these guys on these online dating apps and online dating websites where they are pushing for sex, right? Because if a guy, and it's one of those things, the original reason why this question actually came up was because a woman in our community was asking about women who shame men for men's natural desires. And what happens is, which is something that's happened a lot, especially lately, I don't know if you've seen the Gillette commercial or there's been a bunch of other things out there in the not too distant past where there's been some feminists that have really attacked men and shamed men for approaching women or asking women out or coming on to women or moving things forward. But you have to realize as a man that if you go out on dates and you meet somebody that you really like and you don't push things forward, the woman will probably lose interest. I actually had a friend of mine recently came to me and she's like, hey, there's this guy who I've been going on these dates with. And he hasn't made any moves. He hasn't tried to kiss me, hasn't done any of that kind of stuff. And we've been on, I don't remember how many dates that went on. And do you think he still likes me?  And which goes to something I was talking about on the last live stream, which was the invitation. The invitation, if you want a man to invest in you, if you want a man to pursue you, if you want a man to move towards a romantic sexual relationship with you, it can be a really powerful thing, especially in this day and age to do an invitation, to do an invitation, to show him interest and invite him to make a move. And I talk a lot about that in some of my other stuff here. So what are we saying here in the comment section? Consider stress factors, investment. Chase a man at your own peril. I agree with that. Chase a man at your own peril.  And what he said was, you know, you should make a woman chase you. And so I was wondering, should I be chasing men? And it's like, no, why? Because, so why would a male men's dating coach and a women's dating coach both recommend to the opposite sex that you have the other person chase you? You know, why would a men's dating coach tell men that you need to have women chase you and why would a women's dating coach also tell women that you need to have men chase you and invest in you? Why would you do this? The answer is that because it works, right? So it works if you're a man and you want a real relationship, it works to have the woman invest in you, right?  It's, that's it. It works, it works guys, problem solved. All right, that's it. I guess, you know, we don't need any more advice because we have that right and I'm just kidding. There's a lot of different things. Actually, if you want some really great advice, if you have a really tough situation that you're working through and you want some advice in an anonymous setting where you don't have to give your name, we're doing a free 30 day trial to our Inner Circle program where you can have one of our coaches help you in your personal situation and answer your questions about whatever situation you have, there's a link in the description of this video, if you want that, click on the link and you can get a free 30 day trial to the Goddess Club Inner Circle program that we have and get your questions answered about whatever your situation is and nobody will know who you are. There's also a bunch of cool things that you get in there as well. Like I have this feminine texting secrets that Men Crave guide that you get in there.  You can get it for free and you'll learn all about how to do that over text messages and you can also use those over like with normal face to face talk if we still do that in our day and age. All right, so does anybody have any other questions about anything, Rebecca with the online sites just guard your heart. So online dating sites, are they a waste of time? I don't think that they're a waste of time. I think that they can be a waste of time. I think it depends on the situation that you're in. I think it depends on the city and state that you're in. A lot of people are like, oh, it doesn't matter where you live. It does like let's just be honest here. It does matter where you live. And the reason why some people will say it doesn't matter where you live is because what really matters is what's going on inside. And what really matters is what's going on in your heart and in your mind. So if you meet a lot of guys and they just want sex, it could be him or it could be you or it could be both of you, right? It's not necessarily just him. It's not necessarily just you. And it's not necessarily both of you. I don't know. But so if you want to connect with a man and you want him to feel like you're somebody that he wants to be with in a committed way, with in a committed relationship. And he's in a place where he's looking for that, which I think most guys are looking for that. There's a lot of jaded guys these days, but there are a lot of guys who are looking to get into committed real relationships.  And that all has to do with the heart, right? Connecting with his heart, connecting with your heart, connecting your hearts together. Maybe that sounds weird. Does that sound weird? I don't know. Anyway, another thing is your perspective, right? If you have past hurts, if you have lots of pain from your past and you come to a situation with a guy where you think in your mind, men just want sex. Men don't want a relationship. Men are gonna use me. Men are gonna hurt me. If these are the belief systems that you have, what's gonna happen is you're gonna find evidence to make this true, right? You're gonna find things, even if he's the best guy in the world, you're gonna find red flags, you're gonna create red flags, you're going to look for things that aren't even there. You're gonna make things that aren't red flags into red flags and you're not gonna end up finding, you're gonna think there are no good men out there, right? And so this is what happens. Absolutely Liz, law of attraction. That's right. It's not only law of attraction though. So Helena and I have talked quite a bit about this and she's kind of more into the woo-woo kind of law of attraction stuff. I'm more into kind of the practical things, but it's really like practical, like use this, it works. This is how you use it. This is how it works type of thing. But it's amazing how much those things mix, right? So she kind of gets into this thing of like feeling it and seeing it and it comes to you, you go to it. And I kind of come from this thing of like reprogramming your mind so that you see the things that you want to see, you see things that serve you, right? So whenever something's going on in my life, whenever I like to do little checks, right? Where I question what's going on in my life. And I look at it, I'll look at a belief system that I have. Let's do one with men for instance, we're doing amends and dating stuff right now. Let's say you have a belief in your mind about men. Let's do the, there are no good men out there. And you catch yourself saying that, right? And you want to catch yourself saying things because those are usually associated to belief systems that you have that you don't even know that you have. And so when you catch yourself, it's like your subconscious mind is throwing something out there. And if you can catch it or if you can have somebody else catch it and they're like, hey, did you realize that you said this? You said there are no good men out there. You said men are pigs or you said, men are just trying to use women or whatever. And just look at that belief and say to yourself, does this serve me? Right, if you ask yourself, there's this person out there named Byron Cady and she does this thing where she asks if something is true or not. I don't like that because it's very possible that you might take evidence that isn't good evidence for that thing being true and making it true. I'd rather say, does this serve me, right? Does it serve me to look at men and think that they're gonna take advantage of me? Does it serve me to look at men and think that they're pigs or think that there are no good men out there? Does this serve me, right? And then, oh, Helena's here. Hey, Helena, we're just talking about you. And so, does it serve you? And if it doesn't serve you, then what you need to do, in my opinion, and Helena might have a different, I think she's got a different kind of system for doing this. But my opinion, what you need to do is you need to break that and create a new kind of belief system around that exact same thing, right? Maybe it's a small one. Like, let's take the belief system of there are no good men out there, right? The first thing that you might wanna do is say there are some good men out there. There are a few good men out there. There are good men out there, right? And then look, what you do is you look for evidence of it. If you can look for evidence and you can find evidence that there are good men out there, that'll break that belief. And then you have a chance to work in a new belief around that, right? And so maybe you'll want to keep the idea that there are some good men out there. Somebody was saying something a little bit. So Liz was talking about heal to bring forth a new self and presence in future. I'm totally on board with that. Like, healing is one of the most powerful. Oh, hello from Korea. Healing is one of the most powerful things that you can possibly do in order to reshape the world that you live in. And I actually spent a long time doing this with myself because it's so important. I think that the only way that you can really do this effectively, like really, really effectively is to hire a mentor or get a mentor or hire a coach. Somebody that's outside, right? It's hard to do with friends or relationships. I remember I was in the military, it was 2005. And I was at the end of my military career. And I was dating this woman, her name was Jackie. And it was like the beginning of me kind of getting into a lot of like personal growth stuff. And I remember I was like looking at things and I was trying to find my limiting beliefs. I was trying to figure out what my limiting beliefs were. And there was this book that I got. It was called Mind Lines. And what the book said was to go and talk to people and ask people what beliefs you have that are limiting you in your life. And so I got my girlfriend at the time, Jackie. And I sat her down in this coffee shop and we're sitting there and I was like, I was like, yeah, you know, I'm just trying to figure out what belief systems I have that are really bad. And she was trying to be a great girlfriend. And she was like, no, no, no, all your belief systems are great. No, no, no, everything you think is wonderful.   And I caught something in our conversation that she said that was like a limiting belief system that she had. And I was like, oh, here's one of yours. Now, I don't, I don't even remember what it was. I have no idea what it was. But I said it and she got so angry.   It was like everything she doesn't like about me. Like she was listing off. And I was like, oh, perfect, perfect, perfect.  Yeah, it was pretty funny. But it gave me a chance then to like look at myself. And what I found was that I actually ended up going through some programs. I did some one-on-one coaching and I went through some programs. And for me, those were the biggest, gave me the biggest breakthroughs. You can try to kind of reframe the world around you by yourself, but it just doesn't work very well because you're in it, right? And so when you're in it, it's like, when you look at men, you're like, no, really, there are no good men out there. No, really, men are trying to use women. No, really, and you say these different things that aren't serving you and you don't even realize that it's not the truth because you're so in it that it's hard to reflect on it and see it. Whereas if you have a good mentor or you have a good coach, that coach can sit there and be like, did you hear that you just said there are no good men out there? Did you hear that you just said that all men are trying to use you? Let's say that you're in a relationship with a guy. Let's say you're in a relationship with a guy named Jeff.  How do you think he would feel about you thinking that about him? And it's one of those things where if you have a coach, it's just better. Which is why I'm getting to pitching the Inner Circle program again. If you want a 30-day free trial and you want to have your questions answered, if you want a coach to help you with your situation, you should join our Inner Circle trial. There's a link to it in the description under this video. I think that's it for today. I don't see any other questions about anything, specifically if she chases the man she's in her masculine energy. Yep. Should I not pick up the cleaners either? Okay, well, thanks everyone for being here with us today. And again, thank you so much. We're looking to build a world of partnership. We're looking to create a place, a society where men and women aren't trying to fight and attack each other. We're trying to heal the war of the sexes here. And part of that is, part of that's a logical thing. Part of it's looking at things in a different way. But really, most of this work, if you want a real long-term committed relationship, and this isn't a very popular thing to say, but it's really about doing the inner work. It's really about getting into the heart. It's really about healing what's going on with you and creating a place where you can emotionally and mentally be in a space where you can be in a real relationship and you can connect in the right ways and you have the right frame of mind and you're in a space where you can really relationships are all about dealing with the hard times, right? Because anybody can be in a relationship during the easy times. And the question is, can you be in a relationship during the hard times? Which all relationships go through. There's a myth out there where a lot of people seem to think that a relationship either it just works and everything's great or it's not meant to be. And I disagree with that. Most of the people that I've seen who had that mindset, usually run into a situation where things build and build and build and build until it explodes and then all of a sudden they're in like crisis mode because they think they're getting a divorce because they haven't worked through some of the problems and challenges and issues that are in the relationship and it just continues to put weight and pressure and pain on the relationship until it just explodes. That's right Liz, explode, bomb exploding. That's right. So thank you everybody for being here. Thank you for being a part of our channel. I appreciate you and you guys are the best part of everything that we're doing. So thank you so much. And I look forward to speaking with you again soon. Cheers.