Renewable Technologies Increase Electrical Generation but Bring Their own Issues.
Wind and solar are playing an increasingly important role in our energy supply. Additions of generation capacity to the grid are helped by falling technology prices, aggressive state renewable portfolio standards, and federal investment tax credits. Solar thermal and photovoltaic (PV) added 3,365 MWe of grid capacity in 2013. Nearly 75% of this added capacity was located in California with another 10% added in Arizona. (These figures do not include nonutility, distributed capacity under 1 MW).
Wind capacity expanded less aggressively in 2013, adding 1,070 MW of grid capacity.
While wind and solar have made substantial capacity additions, the most fundamental issue with these renewables has not changed. Wind and solar are critically dependent on local weather conditions and only produce power about 25% of the time.
Capacity factors measure the amount of electricity actually produced compared to the theoretical production by a facility if it operated 100% of the time, 365 days a year, 24 hours a day. The National Renewable Energy Laboratory has calculated that the highest statewide average solar voltaic capacity factors are in Arizona, New Mexico, and Nevada (each 26.3 percent), and the lowest in the contiguous 48 states is in West Virginia (17.2 percent).In contrast, nuclear power has only 9.2% of total nameplate capacity in the U.S., but contributed 19% of the total electricity generated; all of it clean and carbon-free.
In addition to their intermittent generation, wind and solar sources have other issues.