×

What's new in renewable energy on this Earth Day

Wind turbine renewable energy
Timothy Fadek | Bloomberg | Getty Images

Congress passed a bill a day before Earth Day to improve buildings' energy efficiency. The Energy Efficiency Improvement Act was a rare bipartisan effort, co-sponsored by a Ohio Republican and a New Hampshire Democrat.

But that's not the only eco-positive step the country is taking. According to the U.S. Energy Information Administration, electricity-generating companies will add 20 gigawatts of capacity to the power grid in 2015, about 68 percent of which will come from renewable sources.

New wind turbine installations make up nearly half of the total additional power-generating capacity, or 9.8 GW. Another 2.2 GW will come from solar power and 1.1 from additional nuclear capacity.

While the nation is increasing its share of power from renewable sources, it is also working to reduce dependence on some carbon-emitting fossil fuels. Of the 16 GW set to retire from the power grid in 2015, 81 percent is from coal-fired plants. Most of those retired generators are in Appalachian states like Ohio, West Virginia and Kentucky.

Read MoreAre fossil fuels about to become extinct?

The country's geography has a big influence on the renewable sources that crop up in different areas. Growth in wind-generated capacity is concentrated in the Plains states, with 8.4 GW, or 85 percent, going from the upper Midwest to Texas and New Mexico..

New utility solar installations are concentrated in North Carolina and scattered across sunny Southern California. The two combined will make up 1.6 GW of additional power, or 73 percent of solar additions.