The Wayman Farms project was our first off-grid solar system.
It’s unique because it has an off-grid well, which is a large system.It’s a 15 horsepower well, which is enough to run five or ten houses. It has a septic system and has solar and battery, so there’s no utility lines coming in or out of the property.
One of the things that was really difficult, we built a microgrid there. What that means is we could put four or five more houses on the same power system and basically add solar and battery on each house so that it all worked together. We did that because we were planning five houses at that location sharing the well. But the biggest problem that we were trying to solve was the well startup, because the well was so big that it drew a ton of power, so we have twice as much power to start the well as we have that runs the house.
At Wayman Farms, we have three solar inverters. They take solar panels and they create AC power. Then we have two battery inverters. They take DC from the batteries and create AC power and manage the other three inverters.
So we have five inverters that are all really expensive, and then we have tons of wiring and equipment, and then we have a battery that just starts the well.
So we have something like $35,000 or $40,000 of equipment whose entire job is to start the well.
Last week, we did a solar job where it’s just solar panels directly into a solar VFD, which is a variable frequency drive, which runs a well. So to compare, $50,000 of inverters and batteries versus $500 extra for a solar enabled VFD, and we can do the same thing now for 500 bucks that took us 50,000, 4 years ago.
So there’s a big difference in how we run off grid wells versus how we used to do it. The other big problem we ran into at Wayman farms, we could only put one inverter in. In off-grid homes, the inverters didn’t stack. A normal house has a 200 amp main service panel to run everything. Our inverter is 30 amps, and they didn’t let us put a second inverter in and do 60, for instance. So we had to run his entire house on only a 30 amp inverter. That’s a sixth of what a normal house would use.
One of the ways we did that is propane dryer, because dryers take a lot of power. Propane stove, propane heat for the home, and a propane water heater. So the things that are electric in his home, he has LED lights, which are very efficient. He has outlets. He has a variable speed, high efficiency HVAC unit, so for air conditioning. It can heat or cool, but in the winter, we switch him over to propane like if he has a week-long storm. He has a booster pump because his well water sits in a tank and it’s not pressurized. So his booster pump pressurizes it so that he can shower, for instance.
So these are the things we had to do to make this home work, and we built it very efficiently. The home has a fully insulated envelope, so we did the blow in insulation even up against the attic and everything. And this home was really fast to Build. So from when we started the well (meaning we proved that there was water) William moved in 126 days later. So the house construction was really fast. The solar and battery were really fast. It didn’t hold it up at all. It made it faster.
The long story short is it was very expensive and difficult to build this house this way. Five years ago. Because solar and battery technology wasn’t very advanced. Even with our batteries, I think we spent $25,000 on batteries at that house, and for the same size of battery today, we would probably pay 8,000. And now they last longer, so some really big changes.
So one of the things we’re going to have to do at this house … because he wants to add onto his house. He’s thinking of buying an electric car. We’re going to have to go and replace his inverter system with something that’s scalable. The system we use now is scalable. We can do one inverter, which is roughly 30 amps, or we can do 10.
So we can go to as big of a system as we will ever need and it’s very scalable as the homeowner’s usage grows, because that happens over time. The house next to William’s, we built last year. It has two inverters just to start with and three batteries and that’s it. All the equipment fits in about a seven foot space. It’s actually in his laundry room across from his washer dryer.
And that home was built for a fraction of the cost.I think we were $37,000 for the solar battery inverters and everything. I think we were $115,000 at Wayman Farms. Most of that cost was for the well, which we know how to do better now, but solar VFDs didn’t exist back then. They’re a new product.
If we ever remodel Wayman Farms, we’re going to replace the inverter. We’ll probably replace the VFD to a solar VFD and take it off of the microgrid, and then the microgrid would actually be useful for another two or three houses because it has enough power to run three houses.
We may be able to save quite a bit of that infrastructure, and battery costs are coming down, so we’ll probably expand the battery as well.
So that’s what we did at Wayman Farms. What we got out of that is a 1200 square foot home, so three bedrooms, two baths, with a 900 square foot garage. It has all the water it could want. So at my house, I pay $200 a month for water. Wayman Farms has $1,500 a month worth of water that they produce that they get to use at no cost. They just have to maintain the well.
They don’t have a power bill. They don’t have a water bill. They don’t have a sewer bill. It is an amazing house. It’s super fun to be at. They have about one power outage every two years, and it’s usually if they’re out of town and there’s a big snowstorm, and they don’t turn on their generator because they’re gone, and the snow melts off and it starts itself back up.
They have lived there full time for the last four or five years. Their power consumption has gone up quite a bit lately because they planted 15,000 square feet of grass. So their watering system, their booster pump that runs their watering system is running seven hours a day when it used to run one hour a day.
So we’ll probably add some solar panels for that. But if we had five more solar panels, it might be 2,500 bucks. He can add another 15,000 square feet of grass if he’d like.
To compare, at my house, we just planted grass and my water bill is going to go up between 100 and 150 bucks a month. We’ve had four power outages this year.
So his system is something like four to five times as reliable as my power grid. So that’s Wayman Farms. So the well solar system is shared between the five lots there, so I think for the well system, he paid $15,000 for his share. Each of the five lots will pay $15,000 to pay for the microgrid part that runs the well. Then his home was 50,000 for the solar and battery for his home. Abe’s house, the house next to him is 38,000 for the solar and battery for his home, and he’s paying $15,000 for the central system.
That is all of their power and water cost basically included in their mortgage.
It’s really amazing how much things have changed and how affordable it is now.
The underlying theme though is being able to live off grid is really awesome and now it’s actually affordable. Our costs are the lowest they have ever been, equipment keeps getting better, costs keep going down.
It’s a great time to go Off Grid!