Join Date: Aug 2005
Location: Ellicott City, MD
Annoying, no small PV systems
Its really annoying looking around at solar power systems as there is basically no option in the US of UL certified inverters that are low cost and/or low output for grid tie. In my next house I want a system capable of powering the whole gosh darned thing, but in my current town house there is just no way I have the room for that kind of setup and no way the home owner's association wouldn't have kittens. The roof on my house is getting long in the tooth and I figure I need to lay down new roofing shingles in the next 2-3 years or replace everything from the tarp paper up. So I've been looking at solar shingles to intermix some in there, as they aren't that expensive. More so the solar panels, but I know the homeowner's association wouldn't crap themselves if I did that, and hey, why not offset 20-30% of my power use while I am at it (the 30% tax refund from the feds plus what I can get from the state doesn't hurt).
I also figure it would be a good experiment to test it out before my next house.
Well the issue is, the cheapest grid tie inverter is $1500 for a 700w output. I don't need anything near that much power (admittedly 700w is pretty low output). I am looking in say the 200-400w range and more like $500-800. The solar shingles are 17w a piece and about 9ft wide (5in exposure like a normal shingle), at $119 a pop I figure 12 of them gets me around 200w of output at around $1500 not including tax credits. Sure at the price per watt and how long I plan on living here there is no way I am going to see the pay back, but I would want to do this in large part because I want to do something for the environment (and hey, it doesn't hurt as a selling point for the house). With 200w of output that comes out to something like 10-12% of my daily electricity usage with the solar output my house receives (about 4.5 solar hours average daily).
So anyway, no way I am doing it if the inverter itself is going to run as much as the solar shingles. Hell at best I'd be doing maybe around 24 shingles...at around 400w output, that means the inverter would be half as much as the cost of the shingles. I realize the inverter is a write off as well, but I am not outlaying $3000-4000 just to offset 10-20% of my electricity usage when I am never going to see the payback in the amount of time I am in the house (4-6 years).
It just pisses me off looking at Europe, especially England as there are a number of low output (100-500W range) grid tie inverters available at pretty low cost ($300-800). No can do for US use as they are all 50hz.
Maybe some option will become available in the next year or two. Till then I guess just low E glass windows this fall and if I can convince my wife, a higher efficiency hot water heater (ours is 16yrs old) when we put in the bathroom in the basement soonish (this winter???). Of course when it comes down to it, between those two that could easily save 10-15% of our electricity usage.