$1500 for a 500W System

[chemlabrat]

I was an engineer at a nuclear plant for 5 years and while there, the company (TVA), started a program called Green Power Switch. Basically, if you can generate half a kilowatt in solar, they will dual meter and buy the solar from you for 12 cents over the RETAIL price, and it is guaranteed for at least 10 years after you start doing it. On top of that, they'll pay you $1000 up front to offset startup costs. So if you are buying power from the electric company for 10 cents per kW, then they would give you a credit on you bill for 22 cents per kW of solar generated.

(Side note: this is available in many parts of AL and TN. Check tva's green power switch generating partners website for more info)

They get the money to do this by having other customers who want to go green but don't have a desire to produce power buy energy credits from TVA. These energy credits people buy fit the bill for them to pay a premium for solar generation.

So here's my question... if I can build a 500W system (the min to qualify) for $1500, then I could get a 30% tax credit ($450) and a $1000 check from TVA and end up with only $50 in the system. Anyone have any brand suggestions for a grid tie system that can be built in that price range?

[Mike90250]

500W is a pretty small system , as long as i was going to bother with the permits and inspections, I'd go for at least 2,000 w.

Try sunelec.com in florida, they have some grid-tie kits.

Keep in mind, some of the power you generate, will be used in house, before it spins the meter backwards. 500W won't go far at all.

[chemlabrat]

That's a good point. I guess I was just trying to get something for nothing, and while I could probably get close to doing so, the something I get might not be worth much. As for permits and inspections, I have no idea what I would have to have, but unless there's something solar specific required for this program (which so far they haven't mentioned) I shouldn't have any inspections. I live in the middle of nowhere and our county doesn't require any building inspections to be done. I just built a house last year and did most of the work myself and didn't have to get any electrical or building inspections. In our county things have to be built to code only if they are constructed within the city limits. Not that I wont be using a licensed electrician friend of mine to help, but just saying I may not have the expenses associated with legalities.

[Sunking]

What a waste of public money.

[Naptown]

The best way to do this is to to search for solar sellers of which there are many.
500 watts is pretty small and you would most likely be pruchasing a larger system.
For very small systems look for modules in the 220 -235 Watt range so you will most likely need three.
Next figure on using micro inverters as these are more economical for a very small system
Using general numbers as far as cost and for a minimally appointed system your costs should be as follows

About 2.50 a watt for modules 220x3x2.50= $1725
$ 200.00 each for inverters x3= $600
Connector cord, racking etc $350
Misc beer etc for buddy (no tax credit on this) $100
Total outlay $2725
Less
Utility rebate $1000
30% federal credit $787
net costs after credits $938

Now you are looking at a system of 660 watts
If insolation is anything like in Maryland you can figure roughly 1.2 KWH for each watt DC on the roof so you will produce approx 792 KWH per year
I think you are paying about 11 cents a kwh so the system would save you $85 a year and the additional credits would work out to about twice that.
So total savings and income per year of $255
After about 4 years it will pay for itself and the rest is money in your pocket.
Simple return on investment in this case is about 25%
This assumes your state mandates net metering and output for is calculated by a PVwatts predicted output.
Check Dsireusa.org for specifics for your state.
Estimates are informational only and do not take into account tilt azimuth or shading if any.