ECN Forum Forums General Topics of the Trade General Discussion Area Solar Power: The Basics AND Business of it.

Hotline, what did that whole set up cost?

"You can build your ow for less than $200!"

That's the sort of shyster we have to learn to deal with. The only thing 'less than $200' on that site is the set of literature he wants to sell you for $49.95, but claims a 'value' of $109.95. I'm pretty sure that you could buy those books, let them sit on the table, and not generate a watt of energy. Actually making electricity will cost you more.

Gorilla? He sure wants to make a monkey out of you!

$200 sounds like a rudimentary solar hot water system. He probably has you buying a couple rolls of black irrigation pipe, some plumbing parts and a little pump.
It might actually work if you live where water doesn't freeze.
In my shopping I have found PV collectors for around $3 a watt which is half what they were a few years ago.
(Japanese brand, probably made in China)
An off grid inverter is some hundreds of dollars, depending on size. I didn't see a grid tie inverter but I really wasn't looking since you need to buy a certified "system" to do that and there is significant cost to simply getting your product certified. I also think that in a rapidly developing world, the certified system might be obsolete by the time it gets through the process. That is probably good if you are a consumer but does not encourage innovation.

Any of you install oany of these solar panels yet? What Manuf is the best? What is cost for household? 3200 sq ft two people. Total cost including all required materials and install?

This is only a small piece of info needed for a system. All honestly this info is about is important as the color of the house you would like to power with solar. You need to know what you are powering, for how long, Solar conditions at the site, panel configuration, mounting, etc. Then you have to dive into local code and ordinaces... Must go and catch a flight

When you look at the people who get a significant amount of their power from their PV solar the first thing you see is they lowered their usage significantly before they started (better insulation, tighter house, CFL lamps and a whole regimen of energy saving practices) and that might have been where they should have stopped if saving money was their goal.
You really need more than simply saving money to justify this kind of project.

I was using C&D's runtime charts for UPS12-400MR which are high quality deep-cycle AGM batteries used in industrial UPS systems, but cost $300-400 a pop. And unfortunately forgot to divide by 6 electrochemical cells per jar even though I know better, doh! (72 cells = 12 jars.) Serves me right for trying to do the math in my head. I was assuming 12 hours of run-time. Call it 12 batteries, and chop my numbers by a factor of 6. In winter months in northern lattitudes, night lasts a lot longer than day, and you would need larger solar panels and additional batteries to compensate. And that's of course not considering any type of electric heat. You'd need an entire neighborhood worth of roofs to get enough solar power to heat a home in New England in the winter.

Cheapest I'm seeing 85Ah AGM batteries online is about $150. You DO get what you pay for- I clicked a link for one of the cheaper ones, which claims 85Ah on the title, but then in the fine print says you only get 36 minutes run-time at 75 Amps. In this case, the 10 hour run time is slow enough we probably would get close to 85Ah from it, but that sort of deep cycling is very hard on batteries, and there's no word as to the # of cycles. I *know* the $300 C&D above will perform as advertised, and will do so for several hundred deep cycles before performance degrades to 80%.

You just can't beat a generator for this type of backup power, though- even if you have to keep a couple cans of fuel on hand. For the price of just one battery, you could buy an awful lot of gasoline. AND you can do it on rainy days as well as sunny. What happens, for instance, to your 12 hour battery bank during a blizzard that knocks out power lines, coats your panels in a foot of snow, and is accompanied by clouds that blot out the sun for 2 or 3 days? At roughly 1 battery per hour of 800W load, that adds up.

"Snow?" I have heard of this thing.
Cold stuff that falls from the sky, right?

Around here a blizzard is a cup of ice cream at the Dairy Queen.

My outage is most likely going to be in August so temperature and lack of sunlight is not my problem. I do have a problem with feeding the monster. How much fuel do you need to have around? If you don't want to go start the generator every time you want water you need to run it all day but the overall usage is really pretty small.
That is why I think batteries may do the trick.

Alan:

I'm not the EC, but the inspector....

One job is $ 377K, other is $ 251.7K from the app's, which is public information.

Not to say that the 'costs' are accurate, but that's what is on the apps.

One is 2970 panels, other is 2069 panels.

With an average $300 a month electric bill the big one pays back in 105 years but the small system will only take 70 years

Of course that assumes nothing ever breaks and you have a zero maintenance bill. I hope you have a 70 year roof!