Heavy rainfall has allowed the Central American country of Costa Rica to be powered almost entirely by its hydroelectric plants.
Bobby Hollis, a former vice president for renewable energy at NV Energy, is now senior renewable-energy manager at Apple.
Outside Twitter's corporate headquarters in San Francisco, Greenpeace makes its plea for the social media company to "Make our tweets green."
The tech giant says three-quarters of its energy needs are now renewable, with some facilities now at 100 percent.
Take a tour of people's efforts to harness the water, wind, land, and sun in the past and the present, and get a peek at ideas to displace fossil fuels in the future.
Even if they haven't installed a solar array in their backyard, Volt drivers could choose to recharge their plug-in hybrid with renewable energy.
A proposed federal rule change could help American Indian tribes to develop wind, solar, and geothermal power on their reservations.
The Jemez in New Mexico and Southern Utes in Colorado are among Native American tribes seeking to develop renewable energy on their reservations.
The San Luis Valley is rich in solar resources and needs tax revenue, but like other communities, it's moving cautiously in allowing large-scale solar power.
At the rural Navajo Indian reservation in New Mexico, the local utility is renting out solar and wind generators to residents, an easier and less expensive way to bring electricity service to homes.