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Depends on where you live. In Phoenix, $4160 of solar panel will produce roughly $1432 of electricity/year.

Plug in numbers here:

http://pvwatts.nrel.gov/pvwatt...

I used retail pricing here: https://sunelec.com/home/

Damn, they used to talk about payback in 15 years, not in 3.

I've found that many of the payback points to be outlandishly pessimistic. My costs for installing extra installation and changing to natgas for heating paid off in just a few years, when the "experts" were telling me no less than 10.

My biggest issue with going totally solar at home is that I have a spa, which even with a very efficient unit would stress the storage batteries. But I'm expecting even that barrier will fall, sooner rather than later.

Plug in numbers here:

http://pvwatts.nrel.gov/pvwatt...

I used retail pricing here: https://sunelec.com/home/

You have to get them in Barbados, but they're for sale in the US close to this price. UL listed, brand new grade A. A couple months ago they gave away a few megawatts worth of used panels for the price of shipping.

The gov't has been penalizing the import of cheap foreign solar panels since at least 2011. Trump is just more of the same old BS...

Free electricity from sunshine negatively impacts gov't tax revenues, therefore it is against gov't's interests to allow solar panels to be easy to obtain and install for cheap. We've had this technology for decades, yet you STILL can not walk into a Walmart or Home Depot today and load your pickup truck with solar panels (overpriced puny toy panels don't count). Yet you can pick up a noisy and expensive to operate gasoline powered generator at ANY of those big box stores quite easily...

I jumped through all the paperwork and bureaucracy back in 2010 to have 5KW of solar installed on my house. Without an electric bill to worry about paying every month, I decided to quit my full-time day job and haven't had to pay significant income taxes ever since. Without driving around to work every day, I also don't pay nearly as much road (fuel) taxes either.

If everyone managed to jump off the grid tomorrow, the gov't would be up a creek without a paddle due to all the tax revenues drying up. You can bet they aren't going to let that happen. So the war against cheap solar panels continues...

BUY ANY QUANTITY: CL 280 W/285 W $0.25

BRAND NEW

GRADE A

UL LISTED

25 YR WARRANTY

(no association, only a company I purchased from)

http://sunelec.com/

Solar panels at $0.32/wp (PDF) retail are rated at 14.5% efficient.

http://sunelec.com/solar-panel... is advertising grade A panels solar at $0.41/watt in pallet quantities (12kw).

My lead acid batteries are about $80/kwh and good for about 7 years.

How are you going to beat 47 cents per watt with this stuff installed on the buildings that use the power?

I priced solar just 2 months ago, talked to two local companies that sell solar, the end price is just nuts, about $3.40 a watt installed for a 10.5 KW system in Texas.
Then you're probably paying about $2.45/W for supports and installation. Raw panels - in pallet lots or slightly more if repackaged for fewer than 25 panels - are regularly well under $1/W, and you can get B grade (blemished but still fully functional and guaranteed) for about half that.

One of the cheaper places to get them is Sun Electronics, headquartered in Florida but with sites elsewhere. But there are plenty more.

A lot of the government subsidies require installation by licensed contractors (who mark things up substantially more than the subsidy, so it's really government welfare for contractors). But you can still do-it-yourself and be permitted, inspected, and approved in essentially all jurisdictions.

Remember to be nice to the inspectors. Talk it over with them - or the chief of their department - in advance, but do your homework even before that and come to them with a plan or quick questions - not wasting their time (ESPECIALLY on inspections, when they have a tight schedule) is VERY important. When you're ready to go get the permit. Do it THEIR way - their word is effectively the law. Try to get it right the first time (so they don't have to come back after you correct something). Don't cut corners - do it better than a contract electrician. (You can afford to spend a little extra time to make everything neat and better done.)

$0.096/wh. Multiply by 4 to limit discharge to 75%.

Who, other than NASA, cares about efficiency, when you can buy panels for $0.28/watt?

6V*230AH = 1380 watts per battery. 10KW / 1.38 = 7.25 batteries I need to match their energy storage capacity. At $105 per battery that only costs $760. So, do you want to pay $3,000, or $760?

I could build the entire system, with an inverter, battery charger, and a couple solar panels for what they charge for just the battery.

Wow, will those panels really last 20-30 years on a roof? I'm picturing myself spending a lot of time up on the roof soldering replacement panels in!

To be sincere, I don't know. Note they are actually "modules" (no longer individual panels to be soldered together) so they actually might.
In Australia, without aberrant custom taxes, the "installation industry" really took off. The price is about $1.5-$1.6/W installed on your roof and dropping... the 25y warranty was offered to me by the installer (and most probably backed by the manufacturer).

Here's an insight on what a mature "installation industry" has to do with the prices.

And here's a site that seems to offer reasonable prices with the added advantage you can actually ask them about warranty conditions.

http://www.sunelec.com/blog/

$0.59 laminates and $.78 panels.

oops, forgot to sign in before posting.

I'm guessing your employer either ran out of money or resources to actually implement the project, or a few of the major players of the energy industry stepped in and said otherwise.

Actually, just so we can make this argument quite to the point, I'll do the math here for everyone to see. Unlike most of the posts on here, it might also look like I'm actually doing something productive, instead of trolling people for cheap laughs.

According to the article, Wal-Mart will be installing these solar grids on 130 stores. There are roughly 3619 locations in the US alone, and nearly 9000 worldwide. Some of these operate under different names, but that doesn't matter, it's still the same company. The discount centers average around 102000 sq ft, while the supercenters average approximately 197000 sq ft. Now, I'm not going to count the stores overseas, as that's a whole different ballgame with other energy regulatory commissions that delegate what is and isn't acceptable for their particular power grid/division. I'm also skipping over the Walmart Market, Sam's Clubs (even though there are over 500 of them) and a small handful of other store varieties they offer throughout this particular area of the globe.

Lets multiply these numbers and see what we get if Wal-Mart were to implement these in EVERY store in the United States. Mind you, this is also a company with the total asset value of over 180 billion USD:

706 discount stores with an average of 102000 sq ft. 72012000 sq ft.
3619 super centers with an average of 197000 sq ft. 712943000 sq ft.
Combined, the total is 784955000 sq ft.

The other reason I didn't count Sam's Clubs is to account for skylights. Even though Wal-Mart will ndoubtedly find a cheaper supplier for solar panels, we'll use this illustration for general purposes.

http://www.sunelec.com/sun-laminate-245-watts-3050-vmp-p-1590.html

Taking the total square footage of these solar panels (18.33), we'll divide the total number of square feet of Wal-Mart's combined roofing by the approximate (rounded up, again accounting for skylights) square footage of the solar panel. The result is (rounded down) 42815727. That's the total number of solar panels needed. Not including labor, wiring, etc, the initial cost would be approximately 8 billion USD. Wal-Mart's revenue for 2011 was nearly 422 billion USD.

Taking the number of solar panels needed produce roughly 245 watts apiece. Remember that previous number? It's about to get a whole lot bigger. Roughly 10.49 billion watts is the total output. That translates to approximately 7.67 trillion killowat hours per month. Also, using Wal-Mart's own data we'll estimate 5400 homes times 3619 locations. The total minimum number of homes that could be powered is 19542600. The census bureau estimates there are 160 million homes in the united states. 19.5 million is approximately 12% of these homes powered by solar energy from Wal-Mart, not including other renewable energy ventures if they so chose. The excess power that could be sold on the grid by Wal-Mart alone would be enough to more than make up the cost in just over a few months, assuming the energy is redistributed at the cost of $.001 per killowatt hour to a major energy provider, and not directly to homes for twice that cost, which would still undercut most potential competitors by roughly 50%.

The fact that it seems you don't comprehend the enormous business potential behind such an obvious business venture bothers me to no end. It's right in front of you, yet you choose not to look. Goddamn, dude, I hope you're just toying with me.

Well...
A fairly small bit of googling will get you readily assembled panels for $1.50/W. http://www.sunelec.com/solar-panels-c-5.html

Admittedly, these require actually mounting on the roof, and grid-tie inverters.
But let's ballpark these at $3/W.
In sunny Scotland, I pay $.25/kWh of power.

A 1kW panel produces around 900kWh/year of electricity.
( http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php)

At current prices, this 1kW panel would produce $225/year, or payback (neglecting interest!!!) in 6 years.
And I've just got notice that bills are going up 10%.

For 'solar laminates' - these are the bare glass panels with solar cells on which need a frame made, the cost is around $1/W, so payback can be lots sooner in some cases.

(this assumes that I can simply backfeed the meter. In the UK as it stands, you cannot do this)
For places with lower electricity prices, payback is questionable.

Not in Scotland I think. Not $10,000. That's not thrifty at all.

Here are panels for $1.40/Watt. http://www.sunelec.com/sv-solar-panel-190-watts-1740-vmp-p-1652.html Use them five hours a day peak equivalent for 30 years and that is $0.025/kWh. Wonder where you get your numbers?

OK. Kyocera 135W panel is more than $300 is still a square meter in area and weighs 27lbs. http://sunelec.com/index.php?main_page=product_info&cPath=5&products_id=571 Unisolar flex cells are $210 for 68W so you need two of those. http://www.google.com/products/catalog?q=flexible+solar+cells&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=shop&cid=1196353780637427779&sa=X&ei=-mzrTc_VOYPegQeZ3P3YCQ&ved=0CHsQ8wIwAg

It's actually starting to make more sense.

Previously it had to be subsidized and was more of a way for offsetting your costs to taxpayers, than to the Sun ;).

But from what I see the prices are dropping: http://sunelec.com/index.php?main_page=index&cPath=5

Currently average retail electricity costs are about USD0.09 per kWh (grabbed from DOE). So: ( 1.60 per watt ) / ( 0.09 per kWh) = 2 years.

The sun doesn't shine brightly all the time and there are installation costs etc, so the payback time is about a multiple of that say 8-10 years?

Did you give them a call? They certainly list them: http://sunelec.com/index.php?main_page=kaneka_gsa60

What are you talking about? You can get a full 2 kilowatt system with a 2.5 kW grid tie inverter for about $7,500 installed. That's pre tax credit. You get the cells here. These start as low as $2/watt, but the cheapest in stock right now is $2.40 ($4800). Add the grid tie inverter, available here on sale for $1825. That's $6625. You should have no problem finding someone to instal the whole thing for $1000. That ought to be enough of a system for most people, assuming they use gas or heating oil for heat in the winter. You should build up a high enough balance over the year to run A/C in the summer without difficulty.

I'm going to be setting up such a system within a year or so, once I move into my new house.

I'm talking just the panel consumer cost. I.e. you walk into a store and that's your price for the panel.

The panels coming out of China next year are expected to be low cost do to lower manufacturing.

I am not talking about the converter.
Like these:
http://sunelec.com/index.php?main_page=index&cPath=5&zenid=2cb58ed84ab020ff9956e7bcdaa79691

eBay or Craigslist. They don't come up real often.
And the only places you see them on Craigslist very much is where home-solar installs are common,,, which means California & the desert states.

Also another option is to look for B-grade panels--these are either cosmetic blemish or non-UL panels. The potential problem there is that these panels may not qualify for gov't rebates (assuming you are going to do a qualifying system). Even though they are new, they may lack the usual warranty as well. http://www.sunelec.com/ has some at the moment, look in the yellow panel that has the title "World's lowest price $2.98/watt". A grade-A 180W panel would cost around $800, where the non-UL panels they have are priced at $550.

It is also an option to build your own by buying cells and connecting and building an enclosure for them, but this has consequences too. The cost of cells to build a 180W panel is around $300 on eBay right now, but DIY panels will not qualify for any rebate programs. Most people who try to seal their home-made enclosures end up with moisture or mildew problems, so the most-dependable way seems to be to use non-wood materials and to provide small venting on the top and bottom while preventing rain from entering through the top.

Humidity seems to be the arch-enemy of all photovoltaic panels.... The humidity itself kills the panels (both home-made and commercial) and the humidity comes from clouds , so if you get a lot of rain you won't get much from solar power anyway, and maybe should consider hydro instead.

....Also it is observed that home-made panels tend to suffer more reliability problems, but then again, they can be made so that they are easier to open and repair. If you have a commercially-made panel that suffers an internal failure and is out of warranty, it can be quite difficult to repair it to be useful at all because of the way these panels are manufactured. The panel is a few layers of plastic laminated to a piece of glass (and cells and wiring stuck in there somewhere) and there's no way to separate the thing non-destructively.
~

I think that you misread me. That's the renewable energy subsidy if we gave wind power the same 'subsidies' that are 'given' to nuclear power. This system was set up by the Price-Anderson act

Thanks for the link. I didn't know the industry paid for insurance. I went ahead and both saved it to my hdd and bookmarked it.

Many people have battery banks to store the energy their solar, wind, or hybrid systems generate.

Don't get me wrong, but while people do it, it's not globally economic to do so. Most people who do these systems do so to avoid the expense of running line power to them. Meanwhile they do things like run special refridgerators and use hydrocarbon method of accomplishing tasks such as heating their home, water, and cooking. For example, solar power will make sense much more quickly in Sunny california with high electricity costs than ND with it's cheap electricity.

First, North Dakota isn't good for solar as you say but the state is a great site for Wind Gennies. As is SD and Minneasota. MN, where I live now, generates several megawatts of power by Wind Gennies. While it may be mostly those living off the grid in the US who's doing it, it's not the only place solar panels and batteries are used. The same think is done in the third world. In Africa one or more NGOs are going into small villages where they setup solar panels and battery backups to power lights, radios, refrigs, small tvs, and such. The lights allow children to read and do homework for school while it's dark. The refrigs allow medicine to be stored, and the radios and tvs keep the people informed about the world. They are also used for educational purposes. The IEEE's Spectrum had an article about how some people started a business in South Asia building solar energy systems they then sold in remote locations and other places without electricity. The business created jobs manufacturing them, it also allowed those who bought a system to improve education as well as earn more money. One example was of a person who ran a repair shop, he was able to use lights so he could work when it was dark thus he increased his income. In another Spectrum article they described how a group of EEs went into a remote village; in Cambodia, Thailand, or Veit Nam, I don't recall which, and setup a transceiver with a tower for the antenna so they could have radio communications with the outside world. Using a "home built" PC and a bike converted into a generator, the group was able to offer the village internet access as well as voice radio. If they wanted to power the system all they had to do was pedal the bike. If they had setup a solar panel the bike could of been for backup.

Fact is you only have a few years to make back the investment because the batteries degrade, eventually needing replacement.

Sure, the batteries eventually need to be replaced, however batteries today last longer than the deep cycle batteries of yesteryear, and they're cheaper. Batteries can now have 10 year warranties with 20 year life expectancies. Here's one with 7 year replacement(pdf), and 3 year prorated warranty for a total of 10 years. As for solar panels, they can be rated 20 years or more. The same with the chargers.

Ok this site has batteries inteneded for renewable resources for sale. The L-16HC seems to be the best deal, for the amp-hours. It's a 6 volt battery that has 420 amp-hours of capacity. That's 2520 watt/hours. Divided by it's cost of $288, that's $114 per kw/hour of capacity, and it's only rated for 3-6 years of 20% daily discharge.