For well over a century, the primary source of renewable energy in the United States has been hydroelectric power. Hydro plants produce more than 6 percent of the country’s electricity. In places like New York state, home of Niagara Falls, the percentage is much higher.
This past March, a major milestone was reached when non-hydro renewable energy sources outproduced hydropower for the first time. During that month, nearly 7 percent of the country’s electricity was produced by a combination of wind, biomass, geothermal and solar generation. By far, the largest contribution came from wind power, which reached the 5 percent level for the first time.
Renewable sources such as wind and solar power have been expanding rapidly over the past decade and this trend is accelerating. Wind energy is booming in Texas and Midwestern states. California is leading the nation in solar energy, particularly on the utility scale. Many studies project renewables to reach the 25 percent level within the next five years.
As encouraging as these developments are, renewables are still a small part of the big picture. Coal is the largest source of electricity in the country and natural gas, the use of which is expanding rapidly, is the second largest. Nuclear energy, despite all the controversies, is still No. 3 and renewables — even combining hydro and non-hydro — remain in fourth position.
The evolution of the electric grid is a dynamic process and is moving in the right direction. However, there is still a long way to go in the cleaning and greening of our electricity supply.