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Bob McGovern · 02-14-09, 05:15 PM

Five and a half years ago, I bought 32 acres of the nakedest prairie imaginable and started building. The land was cheap because no utilities came near it (sadly, that condition will change next week. Darn.) With a blank slate to start with, lots of sun, and absurd winds the decision to go off grid was obvious.

Nothing is finished exactly. And there are a few things I would do differently, looking back. But for the most part, the result is amazing: Two of us live in perfect modernity and comfort, running a 1200 sqft house and a full-time (60 hr/wk) cabinet shop off eight PV panels and a small wind turbine. And our total annual living costs are under $500, in one of the most brutal climates anywhere. This stuff works, it's easy, and it's cheap.

Most of our heat comes from passive solar, perhaps 80%. Active solar (in-floor radiant tubing driven by solar hot water) supplies a baseline via the floor slab; a small woodstove acts as a kicker but only runs a few hours per night. Domestic hot water is preheated by the same solar thermal, then boosted up to shower temperature by a demand propane heater. House is all steel and insulated with water-based expanding foam derived from soybeans. Shop is Arxx insulated concrete forms with cementboard siding.

We have a hybrid solar/wind electric supply, about 1200 installed watts of each. Wind provides two thirds of our power in winter. In summer, it's about half and half. The PV panels are on Zomeworks trackers and the turbine is an 8 ft Bergey XL1. Twin inverters only supply 60A at 120/240 modified sine wave, but that's been plenty. Daily consumption is a steady 4.5 kWh. We make more power than our batteries can store, most of the time. Excess energy is dumped into the hot water storage tank. The batteries are immense -- roughly 10,000 Amp-hours at the 100 hr rate, or enough to last 45 days with no charging inputs under normal usage.

Telecom tearouts. That's key to the whole business: really big batteries!

Finally, we have a rare water well out here, but the water isn't real good. So we have 1000 gallons of rain catchment for drinking and landscaping. Wish we had a bit more, since we get only 8" of rain a year. We can go months without precip.

Looking forward to trading ideas. I can post photos is that's allowed, and I'm always happy to answer questions.

Bob...

02-14-09, 05:15 PM	#1
Bob McGovern Lurking Renovator Join Date: Feb 2009 Posts: 24 Thanks: 0 Thanked 0 Times in 0 Posts	Thanks for the forum; WY offgridder here Five and a half years ago, I bought 32 acres of the nakedest prairie imaginable and started building. The land was cheap because no utilities came near it (sadly, that condition will change next week. Darn.) With a blank slate to start with, lots of sun, and absurd winds the decision to go off grid was obvious. Nothing is finished exactly. And there are a few things I would do differently, looking back. But for the most part, the result is amazing: Two of us live in perfect modernity and comfort, running a 1200 sqft house and a full-time (60 hr/wk) cabinet shop off eight PV panels and a small wind turbine. And our total annual living costs are under $500, in one of the most brutal climates anywhere. This stuff works, it's easy, and it's cheap. Most of our heat comes from passive solar, perhaps 80%. Active solar (in-floor radiant tubing driven by solar hot water) supplies a baseline via the floor slab; a small woodstove acts as a kicker but only runs a few hours per night. Domestic hot water is preheated by the same solar thermal, then boosted up to shower temperature by a demand propane heater. House is all steel and insulated with water-based expanding foam derived from soybeans. Shop is Arxx insulated concrete forms with cementboard siding. We have a hybrid solar/wind electric supply, about 1200 installed watts of each. Wind provides two thirds of our power in winter. In summer, it's about half and half. The PV panels are on Zomeworks trackers and the turbine is an 8 ft Bergey XL1. Twin inverters only supply 60A at 120/240 modified sine wave, but that's been plenty. Daily consumption is a steady 4.5 kWh. We make more power than our batteries can store, most of the time. Excess energy is dumped into the hot water storage tank. The batteries are immense -- roughly 10,000 Amp-hours at the 100 hr rate, or enough to last 45 days with no charging inputs under normal usage. Telecom tearouts. That's key to the whole business: really big batteries! Finally, we have a rare water well out here, but the water isn't real good. So we have 1000 gallons of rain catchment for drinking and landscaping. Wish we had a bit more, since we get only 8" of rain a year. We can go months without precip. Looking forward to trading ideas. I can post photos is that's allowed, and I'm always happy to answer questions. Bob...