Cost of Solar Photovoltaic power low and getting lower.

The costs of solar photovoltaic energy are substantially lower than believed, according to researchers at MTU

- price of solar cell panels has fallen by 70 percent since 2009

- the life expectancy has been underestimated - 30 years should be possible

- the rate of deterioriation in performance of cells has been overestimated - rather than 1 percent per annum, it is more like 0.1-0.2 per cent.

- external benefits such as reduction in pollution and greenhouse gas emissions are frequently not considered.

http://www.mtu.edu/news/stories/2011/november/story57349.html