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.
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.
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.
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.
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.
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.
Apple is doubling up on solar energy at its Maiden, N.C., data center, and plans to make it run entirely off renewable energy by the end of 2012.
With lots of land suitable for solar and wind, the Army creates a task force to accelerate its program to get 25 percent of its energy from renewable sources by 2025.