The company I work for recently started installing photovoltaic systems. I've worked on 2 of the jobs (1- a 6300 watt system, the other a 3000 watt system), and my initial impression is that going on the roof sucks (to put it bluntly). I don't mind doing all the other work involved, but I really don't like working on the roof. I am a strong believer that these solar panels are going to be huge money makers in the next 15-20 as the demand for energy increases and I'm just curious as to what other electricians experiences have been using or installing them.
In my part of the woods, in lower NY, even with tax credits and rebates, there is still a 12-15 year payback for most systems (of a reasonable size). Many of the PV arrays carry a 10 year guarantee, so the payback may not occur until after the panels have failed. So ..... very little work in this part.
#58206 - 11/02/0510:16 PMRe: Installing Photovoltaic Systems
The rules regarding backfeed to the grid as I understand, are that if you have batteries in the home to store power for use during low/no light, you cannot feed back to the grid. You can feed back to the grid if there are no storage batteries in the home, and you use whatever you produce (if you can) during sunlight. I think the next good way to get large numbers of residences off the grid, will be the further development of residential fuel cells. Then it doesn't matter if it is sunny outside, or not, or whether it is fall and my roof has leaves on it.
#58208 - 11/03/0512:05 AMRe: Installing Photovoltaic Systems
I have been watching homeowner maintained energy schemes since the 70s and I have never seen one that made the customer a dime. You would be money ahead if you just bought T bills with the money you would spend on these ideas and use that money to pay the bill when energy gets expensive enough to make anything "off the grid" attractive. Most roof mounted systems compromise the integrity of the roof and got tossed when the roofer explained why they needed a new roof. Add that to the "cost". Who fixes a solar system or comes up with proprietary parts when the manufacturer goes belly up? If a utility, with central management and a trained maintenance staff can't make money with PV arrays, how can a homeowner do it?
#58209 - 11/03/0502:13 AMRe: Installing Photovoltaic Systems
I've seen a few systems installed here on gas stations and the like. They are purely for backfeeding, no batteries at all. I think that the rebates are big enough here in CA, and we (Chico) get enough sun to make them work well that it may be economically feasible. What most ignore is that the output of these things decreases from the day they are brought into service.
I"m not sure how valid this statement is, but I've heard that the total energy that goes into making a PV panel exceed what it will put out in its lifetime. They are just big silicone chips! If anyone has ever gone to a chip fab plant, you know how much energy, fresh water, and knoxious chemicals/acid goes into one, not to mention all of the waste and air/water polution that comes out! They are not that "green" of a product!
#58210 - 11/03/0506:36 PMRe: Installing Photovoltaic Systems
In Germany we got sort of funny and positive situation with regard to PV energy. It is more or less mandatory to sell all of the pv energy to the Poco at about .50€/kWh counted by a second meter, whereas you buy your own consumption at about 0,14€ depending on your provider.
There is a law in favour of green energies guaranteeing prices for a certain period or time in order to push these new technologies.
This means there will be quite a lot of practical experience in the near future regarding reliability and maintenance of such (at the moment economically senseless) projects heading for a future w/o oil.
Maybe I can give some link with more details in the next days.
#58213 - 11/03/0509:01 PMRe: Installing Photovoltaic Systems
Shockme: I'm not to far 'south' of you. THe majority of the solar I have inspected (resi) is connected to backfeed the grid (PSE&G) State BPU says that the utilities HAVE to buy generated power.
As to the $$$$$, not my thing.
BTW, Middlesex Water Co is now installing 'Phase II'; the second half of a 500KW solar system at the treatment plant. 1/2 is on the roofs(3); the 2nd half is basically 'on the ground', over a buried tank field. There plan is to use all the green power for the plant, not to dump into the grid