Over the last 5 years, the price of new wind power in the US has dropped 58% and the price of new solar power has dropped 78%. Utility-scale solar in the West and Southwest is now at times cheaper than new natural gas plants. Even after removing the federal solar Investment Tax Credit of 30%, a recent New Mexico solar deal is priced at 6 cents / kwh. By contrast, new natural gas electricity plants have costs between 6.4 to 9 cents per kwh, according to the EIA.
(Score: 1, Informative) by Anonymous Coward on Monday May 25 2015, @09:21PM
> FWIW, solar cells *do* wear out. I'm not sure how long it takes,
All modern solar panels are guaranteed to produce at least 80% of their rated capacity at 25 years of age. [energyinformative.org]
Actual in the field results [nrel.gov] seem to be better than that.
(Score: 2) by kaszz on Tuesday May 26 2015, @07:59AM
According to a quick look in the above document the solar cells degrade with approximately 0.5% per year. The time in years it takes to degrade to 80% compared to when new is:
years = log(0.80) / log(1-.005) = 44 years
The amount of degradation at a specific year is:
Lost capacity in part of full (1) is: 1-(1-.005)^year
Ie after 44 years 1-pow(1-.005,44) = 0.20 of full capacity has been lost.
And these calculations is a rule of thumb, statistics.