Only 10% of United States electricity is generated by renewable resources. Which renewable source supplies most of that 10%?

1. In the United States, renewable resources generate only about 10% of total electricity. 2. Of that 10%, hydroelectric power is the primary contributor, ahead of the other renewable sources. 3. Wind, solar, and biomass all contribute to the renewable total, but none of them is identified as the primary source the way hydroelectric power is. 4. This heavy reliance on hydroelectric power within the renewable category is one reason total U.S. renewable electricity remains a relatively small share overall. _Source: OpenStax College Physics (CC BY 4.0), Ch 7 "Work, Energy, and Energy Resources", section 7.9 World Energy Use_