Dive Summary:

• The cumulative installed electricity generating capacity of wind and solar power combined now represents 4.72 percent of United States capacity.
• If other renewables – such as hydropower and biomass – are added, the renewable figure balloons to 14.86 percent of the country’s total generating capacity.
• Wind generation is likely to decline in 2013 due to the expiration of federal tax credits that gave benefits for building new installations; utility-scale solar should continue to grow in the coming year.

From the article:

In the excitement over the news that all new U.S. electricity generation for September 2012 came from wind and solar, as reported in Federal Energy Regulatory Commission statistics, the bigger picture went less noticed.

The cumulative installed electricity generating capacity of wind is now up to 4.43 percent of the U.S. portfolio and, adding solar’s rapidly growing 0.29 percent piece, the two biggest potential renewables resources are at almost 5 percent (4.72 percent) of U.S. capacity. ...