Economics of renewable energy

Cost per watt is the big driver of PV. I am now able to buy PV, in small quantities of under $.60/watt! The first PV I bought was close to $10/watt. In many ways, panel efficiency doesn't really matter. If you get 100 watts of out put per square meter instead of 110 say, unless the price is comparable, it isn't going to change most installations much. That said, higher EF at lower cost is a win/win.

Icarus

 

IMHO the key metric is $/kwh for generation plus $/kwh for moving power for demand. Here today we have on-shore wind having the lowest cost per unit energy, but often this is geographically and chronologically not the best fit. Infrastructure including storage may be more expensive compared to other renewables. There have been studies that wasting some wind may be less epensive than storage.

On storage hydro is the cheapest, but isn't available in most of the world. Compressed air according to a california study may be next if you have proper geological formations. DOE is also looking to batteries and hydrogen storage.

Solar costs unlike onshore wind should still be falling. Part of the problem is regulatory, and these regulatory burdens may be higher than the government subsidies. A feed in tarrif along with changed federal regulation could greatly increase solar. In california and hawaii better infrastructure are needed before storage is a problem. By then hopefully some of the wind experiments will have made storage affordable. Solar should get installed faster than wind in this country starting in 2016.

Offshore wind really is more expensive than solar in many places today. Gulf coast of texas, coast off windy places in the north east coast can fill in lower costs, since solar is more expensive here and doesn't provide a large percentage of energy. Offshore wind like solar should see decreasing costs in the US. Onshore wind is about as cheap as it is going to get.

All the forms are needed to make a large dent in energy demand.