Auream said:Xnarg said:Auream said:Xnarg said:jw530 said:...Think about it - if solar were that good, energy companies would be putting up football sized field solar arrays by the thousands in the desert. It would be more cost effective for a large utility to go solar than thousands of individual households.A lot of energy is lost in transmission and distribution, probably in excess of 1/3.Source?I can't find the graphic that I've previously posted which shows the percent of energy lost in generation, transmission, and distribution.

OK, well I'll do your research for you.

Wikipedia said:Transmission and distribution losses in the USA were estimated at 7.2% in 1995

Yes its wikipedia, but a source is linked for the quote:
http://climatetechnology.gov/library/2003/tech-options/tech-opti...

So as its 7.2% (at leastof 1995). I'm sure it could be higher by now, but likely no more than 8-9%. Still a long way off from 1/3, which sounds patently ridiculous on its face, prompting me to do the research. As I suspected, the number is far less.

I think the 1/3 may be a bit on the high side, but the 1995 number was not for long-distance losses, although in true government fashion, no disclaimer or info on how their number was arrived at. The use of a number of 7.2% rather than using 7-8% estimated may look to the casual observer like a legitimate number, when I would have my doubts, based on the laws of physics (see above for computations of power loss.)

My basic comment on the above is that there ARE huge grids going into the deserts, the radical conservancy groups are trying to stop them, but they are still going in, so they must think the losses in transmission and distribution are acceptable for them (the power companies implementing the technology.)

AbbaZabba said:Big news...
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system is still not installed... just going through plans. There is more room on the roof... tempting to see how big of a system will fit and just get that while the rebates are still good.
I'd analyze California AB 920 very carefully before oversizing your solar PV system. According to one comment, it's a stripped-down version of last year's AB 1920, and the rates of this excess electricity could be low enough to make oversizing your system not necessarily a good financial move.

You can read the bill details and history here. Anyone in CA who is looking to purchase a solar PV system and would be on a TOU (time of use) schedule rather than a flat rate schedule should be especially careful. The reason is that a TOU schedule can often result in a net electricity bill credit at the end of the year, but *not* excess production of electricity during that year. This is because a typical TOU plan will charge a lower KWH rate during evening and morning hours (off-peak, when your PV system outputs the least power) than during afternoon hours (peak, when your PV system outputs the most power).

A TOU schedule therefore makes it possible to size a solar PV system that will generate less electricity than you consume. For example, given a 12000 kWh/year electricity consumption, you might purchase a solar PV system that can produce 9600 kWh/year, and end up with zero net electricity costs for that year. You'd have to purchase a solar PV system capable of producing more than an additional 2400 kWh/year before you'd benefit from AB 920. Obviously, if you're on a flat rate schedule, this isn't a factor.

One additional consideration: There's no guarantee (that I could find) as to what the rate would be for that excess annual electricity your solar PV system would produce. You can bet the power utilities will try to make that as small as possible, possibly much less than the electricity rate you pay on a daily basis. Without specifics, how could you know what size PV system in excess of your electricity consumption makes financial sense to buy?

hpmax said:
On a personal level (let's leave environmental issues out of the picture), fundamentally the purchase of a solar cell is a significant upfront capital outlay in return for future savings. Essentially, it should be treated as nothing more than financial investment, just like buying a stock or bond. A grid-tied solar PV system, unlike a computer or a TV or the like, provides no utility that you did not previously have. If you have a choice between spending $30k and saving $2k a year for the next 20 years, or waiting 10 years and spending $10k and saving $2 a year for the 20 subsequent years, I'd say you are much better off doing the latter. There may come a point at which the dollar per watt cost will get low enough that the system will pay back quickly enough that the capital outlay cost is irrelevant, but when you know it will take 15+ years to recover your money, and solar cells are still getting cheaper, that time isn't anywhere close to happening.

Unless of course you live in New York, where electricity rates are fairly high, and there are extremely generous state rebates. I had no idea how good they were until looking at this thread. I plan on buying a new house soon and I'm pretty strongly considering installing PV solar panels, as well as a solar hot water system (self-made, I'm an engineer and it sounds like a lot of fun and can be done for under $1K). Combined with some insulation and air sealing I could be looking at utility bills under $20/mo.

According to http://www.solar-estimate.org/index.php I'd be looking at about a 5-6 year payback on the upfront capital cost. One thing I could not clarify is if the NYSERDA rebate, which is the most generous, will continue into 2010. Any other New Yorkers on this thread have any more detail on that? It would suck if it ended right before I was ready to install a system (obviously from a financial standpoint it would make no sense to do this without that rebate).

hpmax said:PMonkeyDishwasher said:You make a very good argument, and opportunity costs should definitely be considered. However, as with all purchases where the technology continues to improve, whatever point in the line you choose to buy in will eventually no longer be the cutting edge. I could easily convince myself to never buy another computer because processors, hard drives, and video cards keep getting better. I could do the same with TVs, or cars, or other major purchases.

At some point, though, you just take the plunge and decide you won't regret it.
This is a bogus argument. Yes, technology always changes, and if you wait you can always get something that is "better, faster, cheaper." But there's a big difference between a solar PV array and most technology. If I buy a new computer, I may be tempted to wait because I will be able to get a better, faster, cheaper model if I wait a little while. But there may be a compelling need for me to buy the computer. My current computer may have broken or is unable to accomplish what I need. I will be seriously hindered by not purchasing one.

On a personal level (let's leave environmental issues out of the picture), fundamentally the purchase of a solar cell is a significant upfront capital outlay in return for future savings. Essentially, it should be treated as nothing more than financial investment, just like buying a stock or bond. A grid-tied solar PV system, unlike a computer or a TV or the like, provides no utility that you did not previously have. If you have a choice between spending $30k and saving $2k a year for the next 20 years, or waiting 10 years and spending $10k and saving $2 a year for the 20 subsequent years, I'd say you are much better off doing the latter. There may come a point at which the dollar per watt cost will get low enough that the system will pay back quickly enough that the capital outlay cost is irrelevant, but when you know it will take 15+ years to recover your money, and solar cells are still getting cheaper, that time isn't anywhere close to happening.
I disagree that it's a bogus argument. I had no pressing need to get an HDTV. I wanted one, even though I watch relatively little TV, because it made it more fun to watch sports at home. In theory, I'm saving money by not going to sports bars to watch games as often. However, when I felt like the price was right for HDTVs (which were/are still advancing technologically), I didn't create a sophisticated time-to-recoup-costs spreadsheet. I just decided that I could easily tolerate the cost and would not worry about the marginal advances in tech.

hpmax said:People get grid tied solar PV systems for 2 reasons: because they think they will save money or because they want to have that "green" feeling. If you want the latter, consider that money spent (either by you, or the government on behalf of you) on the manufacture of solar cells, is money that isn't spend on researching new techniques to reduce the cost of the cells and hence make them more affordable. If you want the former, then you need to think of it entirely as a financial investment which should be evaluated just like any other.
Now that's a bogus argument. When we (and I'm referring to Americans), overpay for prescription drugs compared to other countries, aren't the profits from our higher purchase prices being used to fund R&D on additional drugs? Why would that be the case with prescriptions but not with solar manufacturers? Is there something that makes solar companies not want to diversify their product line and increase profits?