CA Solar Use Falling Because of Economics 362
mdsolar writes "The LA Time reports that California is seeing a big drop off in rebate applications for solar power systems. It seems that to get a rebate you have to also switch to a time of use rate with your utility. The math is not working out, especially for smaller systems that don't fully cover use during peak hours. The result: homeowners are reluctant to go with solar energy. 'The difference between peak and off-peak rates is particularly large in the 11 counties of Central, coastal and Southern California, where Edison provides electricity service to 13 million customers. Edison charges summer time-of-use rates that range from 29.7 to 35.9 cents per kilowatt-hour between 10 a.m. and 6 p.m. on weekdays. It drops to a range of 16.3 to 18.6 cents per kilowatt-hour from 10 p.m. to 6 a.m. weekdays and all weekend days and holidays, according to documents filed with the PUC.' There is likely an optimal system size that reduces consumer costs, but with things in flux you'd want some flexibility in your system."
Batteries (Score:1, Interesting)
Curious... (Score:1, Interesting)
Cost of Solar Powered Hardware $15,000
Tax rebate and reimbursement from state (50%) $7,500
$7,500 over 10 years $750
Hidden truths...
Property tax increase
Environmental fuzzy save the birds you're killing from the reflection of your solar panels tax
New-soon-to-be-imposed "Green Tax"
So on a reverse Mastercard like commercial for the state and greased pocket goons:
Cost of Solar Powered Hardware $15,000
Suckered homeowners 10,000
Revenue in our pockets from suckered homeowners... Priceless
Re:Batteries (Score:2, Interesting)
Re:Batteries (Score:5, Interesting)
Besides, it's not 100% efficient by any means.
16.3 cents per kw/h. Most systems would be lucky to achieve 80% efficiency*, so a 'stored' kw/h would actually cost 20.4 cents. Then there's the fact that most lead-acid battery systems end up costing ~8 cents per kw/h stored, amortizing over their life, because you have to replace them periodically. So you're up to 28.4 cents, vs 29.7 cents for the peak power. Considering the capital costs to install all this, it's not worth it. Drop the efficiency to a more realistic 60% and the costs become 35.2. Youch.
NiMH might be better, but is more expensive initially. LiIon is the most expensive, degrades over time whether you use it or not, but has the highest efficiency.
Now, oversizing your solar panel arrays and having the storage systems so you can go off-grid entirely, also expensive enough that it's probably not worth it. You still generally end up getting special high efficiency DC appliances and doing your cooking and drying with gas.
As a side note, to show the vast difference between areas, my power is ~8 cents/kwh. Off-peak, if I had it installed, is 4 cents including fuel charge. And people wonder why I'm willing to let the californians install this stuff first.
Answer: With my almost absurbly cheap power, combined with very little in the way of rebates, it just doesn't make economic sense.
*Efficiency in this case is a combined metric of battery, charging system, and inverter efficiencies.
Alternative power storage (Score:4, Interesting)
There is a rather interesting alternative to batteries as power storage - unfortunately its a little expensive on setup costs.
Compressed air storage. The same thing you hear is powering those new cars, its also used in a couple of large sclae power stations world wide (one in the US and one in Germany iirc)
The idea is you store air in high presure cylynders, 6000psi 540 cubic feet of air ones are quite good - these are standard and used for filling smaller cylynders (eg for diving) normally. The advantage is as these type of things go they are relatively commodity while being very high pressure. One of these will store about 1Kwh and is about 3' tall and 1' diameter. Lets say you are going to need about 16kWh during the day for lighting and electricy (you won't need any for air con, we'll get to that)
During the night you compress air into these empty tanks (you calibrate the day use to make sure they are empty by the end of the day) Compressing the air generates heat, so you use water to cool this, you should be able to extract enough heat in the water to fill your average hot water tank 4 or 5 times. This can be used for normal hot water, heating a swimming pool or in colder places/times of year for heating (under floor ideally). Compression is about 80% efficient in terms of energy in to potential electricy generating cpacity of the stored air. However factor in the heat you have stored for hot water and you are doing better than 100% - assuming you do use that hot water.
During the day the compressed air is used to run a gas turbine, you should be able to get about 80% efficency again and be able to run a 2-3 kW generator, however the "waste product" is nice cold air - hence no need for an airconditioning system, you just pump this air around your house.
So overall:
During the night you use 24kWh of electricy at cheap rates to store air into 20 of these tanks.
You also end up with about 24kWh of waste heat used to heat your hot water for free - thats definitely your normal hot water use covered, under floor central heating and probably atleast part of your swimming pool if you have one.
During the day you get about 16kWh of useful electricy, plus you get all that nice cold air to cool your house down (about 10,000 cubic feet at a very very low temperature)
Not only do you get a net out of nearly double what you put in, you are also paying less for what you put in that you would if you used that power normally during the day, add a few solar panels and you are laughing.
The draw back?
Cost, you are looking at atleast $40k to install this type of system, plus its not exactly off the self - all the individual components are but you can't just buy it as a package, be nice if it was though!!
Panels not ready for prime time (Score:3, Interesting)
As far as batteries are concerned this is called "power caching" and can be used without solar. I can store all my power for the next day after charging the batteries overnight when the rates are super low - theoretically speaking that is. The solution, before solar, is to sell people "power caching" systems on the grid and then pull that power down during peak times and during brown/black outs.
I love the idea of solar, but until the cost comes down and efficiency goes up there is very little point to struggle with small home systems.
Comment removed (Score:3, Interesting)
Re:Batteries (Score:1, Interesting)
Re:Good question. (Score:3, Interesting)
I don't think the time of use rate is such a problem. If you size your system correctly, it will be just as "economical" as it was.....(I use the term loosely because I haven't yet seen the numbers run favorable for anything less than 15 to 20 year payout even with a favorable rebate system). Just make sure that you use less than you generate during the day to offset a lot of your cost at night. Peak time is "daylight hours" which is when your system should be operating at its peak, too.
Layne
solar and hybrid myths (Score:5, Interesting)
The math with current photovoltaics will not come out in favour until the fossil fuel rises by a factor of at least 10 times. Does not matter what, how, who, where. They are simply too expensive to provide a reasonable ROI. They also have a very high environmental cost to produce so people who buy them are not doing a lot of good to the environment.
This is a myth often repeated. I'm going to simply point to a google search that will net many informative results [google.com]. You'll find numerous calculations which all come to similar conclusions: solar panels have an "energy payback" of a few months to a few years, and their warranties extend well beyond the point where they become a source of income for the owner. This does NOT apply if you cannot place the panels where they will collect sunlight, or a geographic region which does not get enough solar power; there are plenty of online and physical tools to help with the evaluation of both. Solar power is not for everyone, just like hybrids are not for everyone.
There's one big caveat: wattage ratings for most panels are slightly inflated, because they're based off standardized tests using light sources which generate more light energy than you can find here on planet earth. Some manufacturers and retailers are upfront about this; others are not. Size the system off calculations based on your location, not spec sheets.
Photovoltaics are a gimmick, similar to the hybrid cars which allow metrosexuals and hollywood stars to show off some fake green credentials.
As a horsepower lovin' pistonhead, I eye hybrid owners' "my car runs on lolipops and giggles" attitude with some amusement (buying a car that burns gas does not "help reduce our foreign dependency on oil", if you understand that we have to buy oil from many sources for the nation's economic stability, no matter how much of it we use...and that consumer gasoline usage pales in comparison to commercial sector use, namely, petrochemical and truck/train/plane fuel), but hybrids DO most certainly make sense for heavy urban driving, which is exactly what they were designed for in the countries where they hit the public retail market big time: Japan. When Toyota came out with a full-size hybrid (Camry), they've been popping up all over Boston as taxicabs. The two keys are a)heavy usage and b)urban or other stop-and-go driving. Without the heavy usage, the gas savings don't compensate for the additional energy+materials (and hence additional price), and without the stop-and-go driving, hybrids are no more efficient than cars with similar drag-reducing design but regular powertrains.
Hybrids do not make sense for highway cruising commutes, which many people bought them for in the initial craze, mostly because they didn't do their homework. If your drive does not involve a fair amount of speed changes (ie, heavy stop and go traffic), a hybrid car is not for you. Buy a CDI/TDI diesel, or one of the lighter-weight Honda or Toyota econoboxes from 5-10 years ago. Just be aware, Hondas prior to 2000 or so have abysmal crash ratings (I don't know about Toyotas.) Use the money saved to switch over to energy efficient bulbs, install hot water solar collectors on your house, blow in insulation, buy new windows, etc.
Re:Good question. (Score:2, Interesting)
Re:VRLA-AGM, and nothing else! (Score:3, Interesting)
Re:Whither predictions? (Score:3, Interesting)
Regardless, until the feds hold the power plants to those standards(IE clean up your stacks or pay for the pollution), in raw economic terms they're cheaper.
Still, I've stated it before, but I'd shut down every coal power plant and replace it with nuclear if I could.
Much of the baseload demand could be taken care of with nuclear power, with solar/wind supplimenting, and hydro/geothermal being used for peak demands. I'd use the excess baseload power created by overbuilding on nuclear plants to produce hydrogen, ethanol, or whatever other fuel that'd end up being most economical.
Re:Curious... (Score:3, Interesting)
Re:About Edison's Dirty Little Secret (Score:5, Interesting)
Think about it. The energy companies already know that by strategically timing maintenance of critical generation systems, they can reduce supply and boost profits. It was done in 2000 by the electrical generators, mostly in Texas, and currently it looks like the oil industry might be doing the same to help run gasoline prices up.
I've heard a number of people complain about current regulation and utility policies are blocking the increased use of solar PV energy generation so it's not surprising to here any of the TOU issues coming up now. They are looking out for themselves and the PUC seem to be oblivious to any of this.
LoB
Our new system (Score:4, Interesting)
Prior to putting in the system, we estimated our electrical need, and tried to put in a system that would result in not having to pay anything all year. The system ran about $150,000, and the rebate was around $45,000. It's a large array, but we have space so it's kept in a fenced area next to the house, not on the roof. In our previous home electrical bills ran in the $400-$1000 range depending on time of year. Temperatures easily hit 100 degrees for weeks at a time in the summer, last summer we had a few weeks of over 110 degrees. Our electrical need is also high, since we have to get our water from our well using an electric pump, run our air conditioning constantly in the summer (my grandmother lives with us, and is home all day), and we bought some electric appliances.
Since installing the system, we are averaging a credit of $550 a month, which we can carry for up to 12 months. We haven't used the air conditioning, but now the temps are hitting 90, so we'll see how the increase in sun and the increased use of air conditioning balance out. I expect our credit to increase.
For us, the system made perfect sense. The ROI was originally estimated to be about 7 years, and the panels are warranties far beyond that. We purchased electric appliances because we could use them without worrying about driving the bill up. The exception is we have a gas cooktop, which we preferred for cooking. Not everyone has the space to install the amount of panels we did, but neighbors have been stopping by and asking questions, and a few figured out it would be a good investment for them as well. The panels take up about as much space as 3 or 4 of our trees would have, but those trees (almonds) couldn't produce anywhere near the return.
The initial investment was high, but it made financial sense for us, and we had the space to put up a large enough array to meet all our needs. The rebate from PG&E really helped us in our decision, but they benefit every month with the surplus electricity we produce which goes back into the grid. We're considering getting electric utility vehicles for the orchard maintenance, which may also take a larger initial investment, but should be cheaper to run since we can just plug them in instead of filling them with diesel. We're still doing research into how their performance is.