When we started down the path to build an off-grid, 100% solar home with no grid connection, all electric appliances, and heat pumps for heat (except the slab in the garage and entry foyer, and we hope to later convert that away from propane to an air-to-water heat pump), our friends and even our contractor thought we were a little bit nuts. I mean, the power lines are less than 200 feet away, through an open field, but we just ignored them (both the power lines, and the people).
It was admittedly a modest challenge when we had only the 6.4KW of ground mounts early on, but then we added 3.2KW of vertical panels in early November and had to use the generator only sparingly. And once we got the final 4 KW of panels mounted onto the gambrel roof fired up on Dec 22 (for a total of 13.6 KW over four strings at different angles), we haven't run the generator at all. The lowest we ran down the batteries' charge was 41%. And, it got down to about -11F for a few nights, and the Mitsubishi hyper-heat heat pumps (rated for full output down to -22F) didn't even blink.
I watched the batteries like a hawk all winter, sure that we'd need to curtail power use or fire up the generator, but we just didn't. The most we did was wait for a sunny day to do laundry or run the dishwasher, and we didn't wait at all if it would be inconvenient to do so. The energy efficient building performed at least as well as we had hoped if not a bit better, and the energy-conserving appliances did the same. And I now see that I just don't need to worry and fret. I still have some alerts set up in the home automation system to tell me if something goes amiss or the batteries get too low, but the only things I now see are the "heartbeat" notifications that tell me, "Yep, still here - all is well". The whole adventure has become quite pleasantly boring.
So, if you're contemplating something similar, I can assure you it's possible, and does not require sacrifice. In fact, the whole thing has been easier and more peaceful than going through a typical winter with grid power outages that necessitated the automatic generator running for hours (sometimes days) at our previous home. And, while we didn't do this to save money, I've calculated our payback at 7.8 years using today's utility rates (which are all but certain to increase over time) as the comparator. After that, we're actually saving money.
So, what's next? We're planning to build a combination she shed / guest house over the summer, and give it it's own PV and battery system. We could tie it into the existing house and system without much trouble but I like the idea of a completely separate system for redundancy, just in case. And what the heck - I had so much fun building the first PV system, I'm looking forward to that more than any other part of the build.
It was admittedly a modest challenge when we had only the 6.4KW of ground mounts early on, but then we added 3.2KW of vertical panels in early November and had to use the generator only sparingly. And once we got the final 4 KW of panels mounted onto the gambrel roof fired up on Dec 22 (for a total of 13.6 KW over four strings at different angles), we haven't run the generator at all. The lowest we ran down the batteries' charge was 41%. And, it got down to about -11F for a few nights, and the Mitsubishi hyper-heat heat pumps (rated for full output down to -22F) didn't even blink.
I watched the batteries like a hawk all winter, sure that we'd need to curtail power use or fire up the generator, but we just didn't. The most we did was wait for a sunny day to do laundry or run the dishwasher, and we didn't wait at all if it would be inconvenient to do so. The energy efficient building performed at least as well as we had hoped if not a bit better, and the energy-conserving appliances did the same. And I now see that I just don't need to worry and fret. I still have some alerts set up in the home automation system to tell me if something goes amiss or the batteries get too low, but the only things I now see are the "heartbeat" notifications that tell me, "Yep, still here - all is well". The whole adventure has become quite pleasantly boring.
So, if you're contemplating something similar, I can assure you it's possible, and does not require sacrifice. In fact, the whole thing has been easier and more peaceful than going through a typical winter with grid power outages that necessitated the automatic generator running for hours (sometimes days) at our previous home. And, while we didn't do this to save money, I've calculated our payback at 7.8 years using today's utility rates (which are all but certain to increase over time) as the comparator. After that, we're actually saving money.
So, what's next? We're planning to build a combination she shed / guest house over the summer, and give it it's own PV and battery system. We could tie it into the existing house and system without much trouble but I like the idea of a completely separate system for redundancy, just in case. And what the heck - I had so much fun building the first PV system, I'm looking forward to that more than any other part of the build.
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