People have been asking me for details on how I set up Emily's newly converted 250 square foot backyard storage building art studio to use solar power so here is a run down of the project.
Originally I was going to run 2 20 amp circuits from the house for her to use for power out there to run the lighting, tools and a window unit air conditioner for cooling in the summer and a space heater for winter. But then I happened upon this article from treehugger about getting a basic starter solar power system going for $600.
So, I thought, hmmmm, why not?
And so it began...
I started shopping around on Ebay and doing some research on solar panels. Eventually I want to start buying the bricks of cells and soldering together to build our own panels but that's time consuming and this is something we wanted to get going quickly. I ended up going with a pair of 45 watt panels from UL Solar that I snagged for $218.
In the article mentioned above they suggested going with an 800 watt inverter but I wanted something I could run a circular saw, compressor or pretty much anything I might want to plug into it so I sprung for the 3000 watt Tiger Claw from OSP and let me tell ya, that dude is bad to the bone. I've run my saw, compressor, sander, the pump for the kid's swimming pool, the electric weed eater and a bunch of other things without so much as a hiccup. Now the inverter needs to be grounded and there wasn't a good grounding source near the building so I drove an 8 foot grounding rod in next to it and ran a 6 AWG wire to it. Thank goodness for all that rain we had the week before I drove that rod in the ground!
Of course also as the article mentions you need to have a charge controller to keep from over charging your battery(ies) on those hot sunny days when you're not using much power in the studio. Because I plan to expand the system later I went with the 40 amp charge controller from Coleman Air which I snagged off Ebay for $40.
Now, I kinda messed up on the battery because I just went down to AutoZone and picked up a yellow top Optima deep cycle marine battery for just under $200 that's rated at 55 amp hours. But afterwards I learned I could have got a 92 amp hour battery elsewhere for about the same price. Will keep that in mind as I expand the system because from what I've seen so far battery capacity is the first thing I want to upgrade. But I was in a hurry and wanted to get all this working as soon as possible so there it is. It's performing well enough though. Other than mounting the panels to the roof, running my wiring and cables, etc. that's about the gist of it. I ended up just running one 20 amp circuit from the house for backup power and to run the window unit A/C because while this system will run it, the battery can only keep it going for about an hour before it's tapped. Everything else the studio usually runs on does just fine off the battery though and as I said, I sometimes use it to run power tools and the 1.1 amp pump for the small swimming pool too. The best way to make an investment in solar power pay for itself is to use it as often as possible.
So now, on to some of the questions I frequently get asked about all this:
Wouldn't it have been cheaper to get a generator?
Initially yes but generators make noise that the neighbors might find objectionable and solar panels are very quite, in fact I haven't heard a peep out of them since they got here. Also, generators run on gasoline and as I'm sure you've noticed around the stations where they sell that stuff, it ain't cheap. Sunlight, however is still free. So over the 25 years the panels are warrantied for they will more than pay for themselves.
Wouldn't it have been cheaper to have gone ahead and ran that second 20 amp circuit from the house?
Yeah, it would have been but it wouldn't have been nearly as much fun and hey, we now have a backup power source in case of a power outage. Plus, there again, over time the free electricity will pay for itself.
What if we have a hail storm?
The panels are rated to take a 1 inch hail stone at 50 miles per hour and come with a 25 year warranty. Could we get bigger hail, oh yes, and if we do I'm sure a lot more will be damaged than just the solar panels. Let's hope not to see it.
How did you mount them?
I used hangar bolts tapped into the rafters with a good portion of sealant then attached two by fours which I then attached the panels to. But there are mounting kits you can buy too if you're not a cheapskate like me. ;-)
Are you nuts?
Well, yeah. ;-)