We hear it all the time: “I’d like to go off the grid.” “Produce all my own power—and store it.”
These declarations come from a wide swath of people. They come from those looking at modest solar photovoltaic (PV) investments to power their homes with grid-tied systems and realizing that when utility power goes out, so does their system’s ability to produce power (backfeeding power on the lines is a hazard to linemen trying to repair a grid). Declarations of grid independence also come from people who are fed up with losing power for days or weeks during storms that are becoming more prevalent and more intense.
Yes, we’re thinking of Hurricane Sandy victims of a decimated power infrastructure, but also of the hundreds of thousands whose power goes out regularly in big and not-so-big storms and wait for days while large and overtaxed utilities try to restore power. (Dial up anyone at random in Southern New Hampshire and ask about this, and you’ll likely get an earful.)
And more and more, we’re seeing homes designed and built not just with net-zero (producing your own energy) in mind, but with storing energy as well.
Way Off the Grid
A 16.6-kw solar array provides all of the home’s electricity, which is stored in a bank of batteries. Photo by Mike Negron
Tim Snider’s vacation home north of Flagstaff, Ariz. was designed to be off the grid from the start. It’s powered by a large solar PV system, but it also stores the energy collected in a bank of batteries that are governed by a system to optimally charge them automatically—and automatically conduct load-shedding when power supplies are low.
That’s not just net-zero, but off-the-grid, baby. And it’s by far the coolest off-the-grid application we’ve seen thus far.
How off-the-grid is it? Way off. Snider’s home is miles from the nearest power lines, so the home had to build to be completely self-sustainable. He started the design thinking of powering his home with liquid propane generators. He decided to add 16.6 kilowatts of solar PV to the mix, even though powering the home with generators might have been cheaper. After all, if you’re going to power a home, you may as well take advantage of Arizona’s abundant sunshine.
Following are the green-tech highlights from a feature article written on the house for Electronic House magazine: