Amid the Power Shutoff: Planning for a Resilient Future with Microgrids

The most recent PG&E power shutoffs in Northern California have directly affected more than 2 million residents across 38 counties. Despite these preventative measures, the Kincade fire started last Wednesday, and at the time of this writing, has grown to engulf more than 75,000 acres and threaten 90,000 homes. The Getty Fire in Southern California has already destroyed 8 homes and is only 5% contained.

Strong autumn winds and seasonal fires are nothing new for California, but the intensity, frequency and damage from natural disasters is increasing. What we have considered to be the typical period of California’s “fire season” has also lengthened. Weather is becoming more extreme in general and, with temperatures increasing, these trends are expected to continue.

During the shutoffs, schools close, traffic lights stop working, and hospitals have to rely on generators. The economic impact of the first shutoff alone was devastating. Lawrence Berkeley National Laboratory estimated the cost to the California economy could be upwards of $2.5 billion, with a heavy burden being borne by sole proprietors and small businesses. Insurance plans for small businesses typically cover natural disasters but not planned power outages, making the shutoffs even more impactful.

Figure 1. Transmission lines like these carry electricity at high-voltages across long distances before the power is stepped down and delivered to local communities.

Governor Newsom recently announced a $75 million program to help local governments deal with the impacts of the precautionary power shut offs. Half of the money will go toward local governments, with at least $150,000 to be funneled toward each of the state’s 58 counties.

While the investor-owned utilities (IOUs) will remain the backbone of the state’s electric-utility system for the foreseeable future, a handful of local governments want to join the 46 publicly owned load-serving entities in California. San Jose and San Francisco recently announced their interest in taking over portions of the grid in their jurisdictions from PG&E. Valley Clean Energy Alliance has offered the utility $300 million to acquire the Yolo County distribution system.

PG&E has held strong in their declaration that their infrastructure is not for sale, although the degree to which they ultimately control that decision will play out in bankruptcy court. In the meantime, a number of cities and counties are considering and implementing an emerging solution – developing resilient microgrids.

Microgrids offer a resilient alternative

Microgrids are local, interconnected energy systems that can use power sources like solar, wind, fuel cells and other sources to create a local mini-power grid. The electricity circulates locally and gets rid of the need to transmit power over long distances. On a good day, microgrids function in tandem with the IOU’s supply. In a crisis, they can function on their own.

Figure 2. A microgrid demonstration at a workshop hosted by the National Renewable Energy Laboratory. 

PG&E’s major power arteries sprawl across 2,500 miles, and these high-voltage transmission lines are connected to approximately 25,000 miles of smaller distribution lines. When a major power line is shut down, all of the smaller distribution lines that it feeds are also shut down. Microgrids reduce dependence on these major power arteries.

Microgrids are not cheap, but neither are the power shutoffs. And given that PG&E expects the shutoffs to continue for at least the next 10 years, there is no better time than the present to begin investing in resilient energy infrastructure.

Fremont: Solar grid for fire stations

In 2017, Fremont became the first city in the nation to complete a solar microgrid system for their fire stations. Their system combines 40-kW solar panels on car canopies with 110-kWh battery energy storage systems at three fire stations in Fremont.

The grid for their first station cost $800,000, but the cost was reduced to $500,000 each at the second and third stations. As the prices of batteries and solar panels continue to drop, the price for a similar new system is currently about $300,000.

Figure 3. This Fremont Fire station is one of three that comprise a resilient microgrid.

The cost savings on the project from generating energy is projected to produce a positive return on investment (ROI) after the first five to six years. More importantly, when the power goes out, Fremont’s fire stations remain a sturdy lifeline for the community.

San José: City ownership to reduce costs, increase resiliency

The City of San José is exploring multiple options to form their own public utility. They are looking into developing islands of energy resiliency that can provide support during shutoff events and also help low-income residents purchase solar panels and storage, subsidized by California’s Self Generation Incentive Program, while forming partnerships to help customers participate in group purchases of off-grid inverters, solar panels and battery storage at a bulk discount.

Mayor Sam Liccardo noted that the cost of the first shutoff to San José exceeded $500,000 – and only a small part of the city was impacted this time. The City is also currently gauging public support for a bond to fund such a public utility, which would require a ballot measure.

Borrego Springs: Installing a small-town microgrid

One of the communities most vulnerable to power outages, Borrego Springs has already developed a resilient microgrid infrastructure. Borrego Springs is a small community of less than 4,000 residents located in a remote area of Southern California, and has a single transmission line that brings power to the entire community.

Figure 4. The town of Borrego Springs lies in the desert of eastern San Diego County.

n 2007, a fire knocked out its essential transmission line and left the entire community stranded without power for two days. After restoring power, San Diego Gas and Electric received an $8 million grant from the U.S. Department of Energy to build a local microgrid.

Borrego Springs’ microgrid system was tested in 2013, when a major storm knocked out the same critical transmission line. The microgrid disconnected from the main power grid, and was able to power a gas station, a library and an elderly community.

Santa Rosa: Maintaining climate-smart services

David Liebman, Santa Rosa Junior College’s energy and sustainability manager, is spearheading a $5 million microgrid project funded by a grant from the California Energy Commission to prepare for climate impacts and allow the campus to maintain essential services during future power shutoffs.

The campus’ electric microgrid, powered by solar energy and equipped with a complex control system, can operate independently of PG&E during wildfires, or when escalating threats of fire cause the utility to shut off power.

Figure 5. Parking canopy solar panels that feed the Santa Rosa Junior College microgrid provide both shade for cars and renewable energy.

The campus currently has a $1.6 million, 1-megawatt Tesla battery system, acquired with the college district’s $410 million facilities bond that voters approved in 2014 to fund new construction and other campus projects. The system’s costs were partially offset by an $800,000 rebate from the state.
If microgrid systems expanded to Sonoma county, they could power hospitals, municipal utilities and college campuses, and allow essential government buildings to continue to operate in a natural disaster.

Technological advances open up clean energy options

Advances in renewable energy, battery storage and smart-grid controls are opening up a new future where every household, building and property has the potential to be an energy generator, user and mini-grid operator. As climate change and development patterns increase wildfire frequency and risk these strategies will become of growing importance for all Californians.