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CA Solar Use Falling Because of Economics
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."
Peak means daytime. Solar only collects power during the day. The issue is that the panels were not collecting enough power to cover peak usage needs. Hence, there is nothing to store - it's all being used, and you still need to buy more at higher "peak" rates.
The biggest problem here is that solar panels are very expensive. You need a LOT to cover your usage unless you have also done MAJOR energy usage reduction efforts such as LED bulbs, better insulation, appliances, etc. If you don't take all those measures, the panel's don't make sense financially.
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. 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.
Please help metamoderate.
Off-peak here is 11 hours per day, so I'd need to sustain something like 1kW (at a guess) 13 hours - let's call it 15 for a bit of slack. No, sod it, let's go for a full 24-hour supply at an average of 1kW (I don't have a lot of heavy electrical appliances that run during the day). So that's 24kW/h - and I suspect I'm guessing high there.
Right, let's consider our power delivery system. Forget 12v, to reduce the current draw I'm going to use 24v electrics. This page has a range of 24v to 240v inverters. They run at around 90% efficiency (inverters are very good these days). Lets assume a full load draw of 50A - that's 1200Ah. LED lighting tends to be easier to get in 12V form, with GX53-type replacements being cheap and easy to get. They put out about the same light as a halogen lamp (maybe a little less) for an input power of less than 2W. At most they're going to pull down maybe 15A for a houseful. Let's for argument's sake say it's 10W, because that gives us a total load on the batteries of 60A. We'll split the lights across the batteries to even the load.
Still with me? Good. We have a total power requirement of 60A at 24v, for 24 hours. This is 1440Ah (it's also 1440kW/h, but that's just co-incidence. 24 volts, 24 hours). Let's go look at batteries.
A quick Google suggests the Elecsol 125 batteries might be the way to go - they're relatively cheap, small enough to be handled by one man (28kg - they're not light!) and not too expensive (a little below the £1/Ah price point). With 125Ah capacity, we'll need 24 to cover our day's requirements.
These are 34x17x24cm, and this is where my crappy arithmetic and geometry fails me. I could arrange them on a special stand about 102x68x80cm, or very roughly the size of a small chest freezer. You'd need a bit more room for the services board, and some switchgear, the inverter and the regulator. You'd still easily fit it in your garage, though.