The Evolution of My Solar Arrays


| 5/4/2011 8:24:34 AM


Tags: solar, renewable energy, PV, Cam Mather,

Just as we have tried to evolve as human beings as we age, the solar panels that power our home have gone through an evolutionary process in the years that we’ve lived here. When someone asks me, “What’s the biggest mistake you made when you moved to your off-grid house?” I usually reply, “How much time have you got?” The short answer to this question is that I wish I’d invested in more solar panels as soon as we moved in.

Now hindsight is always 20/20 and I forget that solar panels were a lot more expensive back in 1998. Even so, I wish I’d taken money out of my retirement savings plan and put up more PV. It simply would have made our lives so much easier. But of course, at the time there wasn’t a “Renewable Energy Handbook” (the book by William Kemp that we publish) to refer to, so we had to make it up as we went along.

panels on tripod

When we bought this place there were eight 60-Watt solar panels sitting on the ground held up by two supports, sort of like a pup tent. In the summer, when the sun is much higher in the sky, I knew that I was missing some potential energy and so I convinced my neighbor Ken to help me make a tracker. Ken, the maestro of all things steel and concrete came up with a great design. He even found me a perfect 12-foot pipe to put into the ground. I wanted about 4 feet of the pipe to be above ground. Ken suggested that we could just cut 4 feet off the pipe. I prefer to over-engineer things so I just dug the hole 8 feet deep. That’s the beauty of sand. And when a huge wind storms blows through, I’m happy to know that my solar tracker stand is dug in nice and deep.

cementing pipe

Once the post was cemented in to the ground, Ken fabricated the tracker. He let me do some of the welding, mostly on the parts that ended up below ground. The tracker is great because it allows us to angle the panels to capture as much light as possible. But pretty soon I knew we needed more PV. Our then-teenaged daughters were still living at home back then and they enjoyed watching a bit of TV and having long showers. So Ken developed a steel rack that we could bolt to the existing tracker and we added four 75-Watt panels. As I recall we paid about $10/watt for these panels so they were about $750 each. This upgrade cost us about $3,000. I like to remind people of this, especially when someone tells me how “jealous” they are of us not having a monthly electricity bill.

 

 finished tracker

gdaniels99
5/13/2011 4:16:05 PM

Why are you using PV to heat water? I've always heard it was more efficient and much cheaper to use a solar hot water heater which uses the sun to physically heat the water..which can also be used in winter to heat your house.


elnav_1
5/13/2011 11:00:24 AM

NICE SET-UP! I SEE HOW YOU ADJUST FOR VERTICAL TILT BUT THE PHOTO IS NOT CLEAR ENOUGH TO SHOW HOW YOU ROTATE HORIZONTALLY. HOW ABOUT SOME DETAILS ON THE ROTATIONAL ADJUSTOR AND HOW YOU SENSE THE SUN POSITION AND ROTATE THE ARRAY ACCORDINGLY.





mother earth news fair

MOTHER EARTH NEWS FAIR

Oct. 21-22, 2017
Topeka, KS.

More than 150 workshops, great deals from more than 200 exhibitors, off-stage demos, inspirational keynotes, and great food!

LEARN MORE