mheslep
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Recheck, e.g. solarbuzz. Of course the chart from that solar PV company is using a favourable bracket, which in the US for Industrial systems in sunny climates is now $0.192 per kWh for July 2010, so the chart from 1366 Tech is accurate for that case, especially since they draw the distinction between retail (residential) and wholesale electricity (two horizontal lines). The difference between residential and industrial PV is clearly due to greater installation and distribution costs, i.e. cost of installation scale, which is irrelevant to a figure on costs of PV cell production itself over time - the point of that chart.talk2glenn said:I do not know what methodology the architects of your graph used, because it is more certainly not the case that solar electricity production is anywhere near the level of $0.20/kWh. Current US aggregate production cost is ~$0.32/kWh. This is a customer-cost rate for residential, roof-mounted solar panels in optimal conditions. http://www.solarbuzz.com/solarindices.htm
Solarbuzz prices specifically exclude:talk2glenn said:Because it is a customer-cost rate, it does not include subsidy-added costs, which can be upwards of 50% of net. This implies an unsubsidized rate of ~$0.48/kWh; this is many times higher than the average electricity rates paid by most American utility customers (for reference, average rate was 12 cents in 2009 in the United States, not including demand charges).
solarbuzz said:the impact of rebate programs that are available today in some European Countries, Japan, some States of the USA and through bi-lateral aid programs.
Yes for the moment. If trends continue as shown in the PV cost chart indicating solar PV is dropping 10% per year, then in 5-10 years that will no longer be true for some cases.talk2glenn said:For commercial/industrial electricity generation, costs are lower - between 15 and 30 cents/kWh. Note that this is still significantly higher than the costs of conventional and other alternative fuels.
Well replace 'must be' with 'are more cost effective when'talk2glenn said:Further, solar has one critical disadvantage (shared by other renewables) - geography. Unlike conventional plant technologies (nuclear, gas, coal), in order to achieve these rates the solar plants must be built in "optimal conditions". In the US, this means parts of the contiguous southwest (Arizona and Southern California).
Capacity factor drops (% of daily sunlight available) in less than sunny conditions and thus cost per kWh rises in the E./N. Efficiency (% of incident light converted to electricity) of the PV panels actually improves in cooler climates.talk2glenn said:Efficiencies drop dramatically as one moves east and/or north (for perspective, efficiency drops by about 50% when conditions go from clear to partly cloudy in Phoenix, AZ).
Agreed.talk2glenn said:The typical response from solar-advocates is that efficiency will improve with time. Clearly, this is true.
Er, no. The efficiency of carnot cycle boiler plants are approaching their thermodynamic limits, have been for some time. More can and is being done in traditional heat cycle plants with rejected waste heat - combined cycle plants, and more efficient turbine blades. Though these gains are significant over the total scale of the grid, the efficiency gains themselves are small - unlike those seen in PV. More importantly, the cost of fuels for these plants (nuclear aside for the moment) is only going up, even if coal and gas reserves are plentiful at the moment.talk2glenn said:But it is also true that efficiency ratings for competing technologies will also improve with time.
Solar subsidies may or may not be over done, but not for the reasons you suggest here. PV efficiency is not limited in the way heat engine efficiencies are (http://upload.wikimedia.org/wikipedia/commons/c/c9/PVeff%28rev100414%29.png" ), nor are there limited fuel supply issues increasing costs as in the case of fossil fuels.talk2glenn said:2) We are foolish to subsidize solar technology development to the extent that such subsidies disfavor other, potentially more efficient alternatives. There is no reason the promise of "improved efficiency" should be uniquely solar.
Fossil and nuclear have received much, much more government subsidies in total. We see figures of dollars per Watt produced showing renewables receiving more than fossil/nuclear, but I don't find that metric, by itself, useful.talk2glenn said:Any technology, lavishly subsidized by public funds as solar has been, will improve.
I'm generally in agreement with you here on subsidies and I favor free markets when I can find one. Here, the competition (fossil/nuclear) has been given more subsidies by orders of magnitude in total than solar/wind/etc. Take away the $billions of subsidies given to fossil/nuclear including that which it received in the past, add back in the externalities cost (pollution), then let's talk.talk2glenn said:Policy makers should be asking, is the gain in efficiency/dollar equal to or greater than the gains that could be had by spending the same amount on an alternative fuel source?
These points are addressed by markets. They are not addressed by policy makers. This is why solar subsidies (like all subsidies) are generally a bad thing, from an economic perspective.
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