How Bright Is Renewable Energy's Future?

What's the state of play for renewable energy, such as wind, solar, and hydropower?

With Senate Majority Leader Harry Reid's annual clean-energy conference this week in Las Vegas, many of the country's decision makers will be focusing on these renewable sources of energy. The Nevada Democrat's conference will draw big names, including Interior Secretary Sally Jewell and Energy Secretary Ernest Moniz.

This high-profile event comes on the heels of a report the Energy Department released last week that showed wind energy was, for the first time ever, the No. 1 source of new electricity generation capacity (a distinction it earned in 2012).

Two years after the Solyndra debacle clouded the solar industry, it's looking bright today. A BrightSource solar plant under construction in California is being dubbed the world's largest.

Meanwhile, hydropower just got a rare win in Congress when the Senate easily passed two bills seeking to streamline permitting and construction of hydropower projects.

What opportunities and challenges face these renewable-energy resources and others, such as geothermal? How could storage technologies change the game? On solar power, is its future more in distributed solar (such as on rooftops) or utility scale (such as the BrightSource facility)? How are the economics of natural gas affecting the future of renewable energy?