With the cities of Houston and Palo Alto both announcing big purchases of renewable energy, it shows that prices are at the point where cities can get a significant portion of their energy from clean sources.
Houston's purchase makes it the largest municipal buyer of renewables in the United States.
It's buying enough wind energy to supply half its electricity for the next two years. The 140 megawatts (MW) from utility Reliant (owned by NRG) costs just $2 million.
"Historically, investing in clean energy has been a matter of cost, but wind prices right now are incredibly competitive with natural gas prices, so it's become easier than ever to invest in clean energy. And not only do you get clean air, but you are able to show leadership by making these investments. It shows the world that it's doable," says Luke Metzger, director of Environment Texas.
Purchasing renewable power is a significant way to help cities reduce emissions, says Laura Spanjian, Houston's sustainability director.
"We just reviewed data that shows that since 2007 and the last five years, the City of Houston reduced our emissions by 26 percent," she says. "So we are on the right track and we just want to continue."
Houston has some of the strongest energy efficiency standards in the country and one of the most extensive electric car charging networks.
Thanks to a $6.8 billion investment in new transmission lines, Texas will be able to deliver double the wind capacity to its cities. The state leads the nation in installed wind capacity, which supplies 9.2 percent of in-state generated electricity.
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