A reader from Georgia wrote with a question on our approach to electricity use, and our decisions and experiences with being on or off-grid. The response email quickly became detailed enough to become publishable as a useful discussion of this issue.
We’re on-grid through an electric co-op (Boone Electric), and our electricity use varies strongly with the seasons. Summer is by far the highest because we’re running a walk-in cooler and refrigerators for produce. We also run AC in the house midsummer when the outdoor temperatures get too high, because we have to be able to sleep at night, though we keep the thermostat pretty high by most people’s standards. We also have an electric stove, which gets used heavily in late summer and fall for all the canning we do. We actually have two meters, one each for our house and main packing barn. The latter runs all our cold-storage areas and electric fences, while the house runs our personal needs plus the computer, and grow lights we use to start plants in spring and summer. The graphs below show the last 12 months of electricity use here, drawn from our Boone Electric account. Keep in mind that the billing month is well after the actual use dates, such that the peak in “October” is actually closer to mid-August through mid-September.
The graphs show monthly usage in kilowatt-hours/month. Our cold-storage barn meter peaked at around 650 kwh/month this year, which was hot and dry. Our home meter ranged from 400 – 1300 kwh/month. The highest month was an outlier (the highest usage peak we’ve had while living here) that may relate to AC use combined with lots of late summer canning, though it still seems abnormally high. I can’t explain the data glitch for the missing “August” numbers. For reference, these numbers translate to monthly bills of $60-$130 for the house, and $20-$60 for the barn (including the base fees and taxes, which are around $20 whether or not we use any electricity that month). The house electric bills also includes a fee for a “renewable choice” program which creates a commitment by the electric coop to source at least as much power from renewable sources as is used by the members in that program.
To put these numbers in context, I drew on data from the US Energy Information Administration, which tracks residential, commercial, and industrial electricity usage by state; the latest data are from 2009.
Our annual household average is just over 700 kwh/month, as compared to 1,098 kwh/month in the average Missouri household. That’s still inflated from our actual personal use, as there’s quite a bit of power used for the business, such as the fact that the computer is running a lot more for business use than personal, and we currently start all of our transplants in the house using grow lights, which are a serious power suck (but one that will dissipate when we build a greenhouse for managing transplants). So in terms of actual personal consumption I’d guess we’re closer to half average. In terms of total power use, if our household and barn 12-month averages are combined, they total just over 900 kwh/month, meaning our home and farm business combined still use less electricity than the average Missouri home alone.
We take a number of simple power conservation measures. We don’t have a clothes dryer, virtually never use electric heat, have energy efficient light bulbs in virtually all light fixtures that will take them, and keep various electronic devices on power strips that we turn off when not in use to minimize power drain. We do have a solar hot water system, which we noticed cutting our electricity bills by 20-30% once it went in years ago, and which we like having for the ethical sense of how it works. We do try to target our major hot-water usage (like laundry and dishwasher) around sunny days to maximize its benefits, and there are many days where our hot water is effectively “free”. That being said, we’re not sure it was really economically worth it, and are sure that solar PV (electricity) isn’t for us, because given how little energy we use already the cost of the system never really pays itself back. At our low rate of usage, it’s going to take 30 years for the solar hot water system to pay itself back (and that’s if we don’t have more expensive repair bills like we had this summer on a system that doesn’t seem to be nearly as fine-tuned as we anticipated). It would take a lifetime for PV to pay itself back. Estimates for how fast solar or other renewables pay themselves back often rely on high energy use numbers for wasteful households, not for how sustainably minded homes can actually be run to minimize use in the first place.We could do far more sustainable things with the solar PV money (like invest it directly in our vegetable farm) rather than put it into newly manufactured solar panels which use resources to mine, manufacture, and ship, like just being smart about our energy use in the first place. It’s a similar situation to paying $30-40,000 for a hybrid car, or $12,000 for a normal one that gets 80% as good mileage. I’m happy to see hybrids (and renewable energy sources) being built and purchased as that does help push development of better technologies, but basic personal conservation is still the untouchable elephant in the room of energy options.
Also, being off-grid increases your risk of power loss, and/or increases your costs to buffer that power loss (large generators, serious battery banks), and for a vegetable farm whose livelihood requires keeping lots of vegetables cool in the heat of summer, the cost/benefit of off-grid power just doesn’t compare to the security of grid power (we do have a small generator for emergencies anyway).
Besides, neither wind nor solar are all that cost-effective here in Missouri’s highly volatile climate, especially without investing in some serious backup generators/battery banks which also don’t really pay themselves back. We feel we’re overall more sustainable by staying on-grid and practicing effective conservation, rather than spending gobs of money to “save” that last remaining power cost. Part of our estimates, too, rely on the fact that Boone Electric is extremely well-run and we’ve very comfortable placing ourselves in their hands (they’re even quite respectful of our organic status, happily allowing us to maintain our power lines instead of spraying them, unlike some utilities we know of). In a different setting, we might be more willing to explore alternate options, but we’re quite comfortable with our setup. Effective conservation fits our lives better than the alternatives.