all 9 comments

[–]o08 8 points9 points  (1 child)


First step is to build a home that is super insulated. For the basement consider ICF's. For a 24X32 square foot home this will cost you an extra $6500 in materials cost. This extra cost does not take into account what insulating your basement would normally be, just comparing to a basic concrete pour. The basement should be a minimum r-20.

2nd step is is well insulated walls, and windows, and attic space. Foam is the best but costs considerably more than fiberglass. Nonetheless, this is the best long run cost saver in regards to energy usage. Why oversize other equipment when you can conserve as much heat possible. Make sure there are no gaps in the house and remember that caulk is your friend.

Why the need for massive water tanks? Have a water well drilled. Depending on flow, this can be used for drinking water and geothermal energy. In northern climates, ground water is generally a constant 45-52 degrees throughout the heating season. The installation of a geothermal heat pump takes the energy from this ambient water temperature and creates heat normally delivered through a traditional forced hot air duct work system. If you are drilling for water anyway, the only additional costs are the installation of the geo heat pump which is about $3000 more than a normal high efficiency furnace. Depending on the depth of the well and location from the home, casing, electric wires, extra water pipe would need to be factored into your cost. Often times, government tax credits will offset the cost of installing a geo heat pump. Geothermal is 300% more efficient than the cheapest nat gas costs. You should see heating bills of about $15-$30 month in January.

The next largest cost in geo is the type of loop you decide upon. Closed loop requires a lot of piping and excavation or another drilled well. An open loop system dumps the water into an existing body of water. Standing column open/closed loop systems will reinject the water back into the well. All of these loops cost extra but open loop is cheapest.

At this point, the largest costs are hot water and lighting. Purchase a hot water heat pump. This takes ambient air at 60 degrees or hotter and converts it to hot water. For a family of 4 you would need a 40-60 gallon hot water heat pump. You monthly hot water bill will be reduced to $8 per month. Costs of this will be about $1500-$2000 more than a normal hot water heater.

If you install the geothermal, you can then have the option of a desuperheater connection to the hot water heater. This takes the left over energy from spent gases in the geo process and sends it to your hot water heater. This will reduce hot water heat energy usage by up to 40%.

LED lighting will then take care of your final large energy waste. While initial investment in these bulbs is high, certain governments and states subsidize them to make them affordable.

Forget the fireplace and just put in a wood stove. Fireplaces can often take heat from the home.

Now, you can begin to size your alternative energy electric production facility. If you are yet to purchase land then consider one near a stream. You can then install a micro-hydro turbine depending on head and flow. These are the least expensive energy option as all it consists of is a water catch, piping, and a small turbine. The water is then returned to the stream. Doing it yourself, one of these can cost as little as $10,000. It also has the benefit of being a base power which as long as you find a stream that runs year round, will never fail you. This could also be used as the "dump" for an open loop "pump and dump" geo configuration.

Depending on your location, you can either tie into the grid and sell energy back to the local utility or just store extra energy in batteries. The batteries will cost you an extra $1500-$2000.

A small solar panel would probably take care of summer cooling times when the geo then operates as a air conditioning and water flows are often lower.

At this point you are energy neutral and water neutral.

Source: I am completing a home with this same configuration.

[–]EvilScotsmen[S] 1 point2 points  (0 children)


Thanks for sharing the details. Do you have plans to grow vegetables and rear animals?

[–]slice_of_pi 5 points6 points  (2 children)


The Earthship folks from New Mexico have done lots of work on this...rain, solar/wind energy systems, passive heat. They've built in Sweden IIRC.

[–]wormcasting 4 points5 points  (1 child)


From what I've read about Earthships, I recall that the ones built in colder climates never worked really well over time. Too many problems with humidity and insulation. As the oridinal idea was developped in New Mexico that's no surprise.

Another problem with Earthships is that you can't build them in many parts of the world due to construction laws beeing very specific about what you can and can't do, and Earhships are way to "exotic" to comply with those laws in many cases.

That said, you should still gather infos about the Earthship concept, there's plenty to learn and it will inspire you a lot.

Also check out the Passivhaus institute.

[–]slice_of_pi 2 points3 points  (0 children)


I've done quite a bit of reading as well. The design is flexible enough to work in moist or cold climates quite well; the primary problem is that people weren't thinking ahead when they built and neglected stuff like subfloor thermal & moisture barriers. You're right, the design was created for New Mexico, so it isn't a surprise that a house built the same way wouldnt work very well.

There is a lot of valid criticism of Earthships, mind you, I'm just pointing out that in terms of energy and water use, they're ahead of the curve.

[–]laibach 4 points5 points  (0 children)


I really like this project...

It's made for two people, but you could easily expand it

[–]traztx 5 points6 points  (0 children)


I don't know about the costs, but it makes sense that the answer varies by the location. A tropical home doesn't need energy to heat, and heating a Dakota home would take more than a Louisiana home. Water is easier in some places and almost impossible in others. Maybe you can google around for stuff in your area. For example, I live near dallas and the search terms "energy efficient dallas" gives interesting results.

[–]rhinorocan 6 points7 points  (0 children)


If your planing to dam and utilize water power remember the damage that can be done to the enviorment by resticting water flow. Also check the laws. Water rights even on small rivers and creeks are sometimes governed by international treaties. Large fines can be leved.



If you can, use metal rods to disperse the heat from the fireplace through the floor. There is a way this can be done so that the fireplace heats the whole house instead of just the area in front of it. If you are going to construct the house from scratch, you could place a structure like that into the concrete, place a lever at the connection to the fireplace, and be able to regulate the heat entirely from there. For long term durability and wear and tear, concrete mixed with fly ash and plasticizer (to replace the water) can last longer and be more durable than almost any other material. The use of fly ash helps to reduce industrial waste. There are a lot of interesting experiments being done with polished concrete, concrete embellished with decorative rocks, that would be nice.

As to specific energy needs. I think the United States Environmental protection Agency has worked out some numbers. Don't know how well GE represents it, but they claim to visualize it here: