Central America's new coffee buzz: Renewable energy

That morning cup of coffee gives many of us a needed boost, but Central American coffee farmers have found a new source of energy in their beans: Turning agricultural wastewater into biogas.

An often-overlooked byproduct of the world's favorite stimulant, the water used to process raw coffee beans is usually dumped back into the environment untreated.

In Central America, locals call it "honey water" because of its sweet taste and yellowish color.

Extremely polluting, it is high in methane gas - a leading contributor to global warming produced, in this case, by the fermentation of the coffee tree's berries.

Across Nicaragua, the 1.3 million sacks of coffee produced annually generate pollution equivalent to about 20,000 cars.

Now a pilot project at 19 farms in Nicaragua, Guatemala and Honduras is treating that water, separating out the methane and using it to fuel electric generators.

"Look how high that flame is," said Sarahi Pastran as she cooked bananas in her kitchen at the La Hermandad coffee cooperative in San Ramon de Matagalpa in Nicaragua.

Her stove was connected to a pipe that ran across her lush yard and connected to a biogas generator fueled by coffee byproducts that used to pollute local rivers.

The project was launched in 2010 by Dutch sustainable farming group UTZ Certified, seeking to use less water in coffee growing and use it more creatively.

"It used to cause a lot of pollution... and it smelled," said Francisco Blandon of the wastewater that his family farm used to produce.

"A lot of families live by the river. They bathe there, wash their laundry. It gave them rashes and intestinal parasites when they drank it," said Blandon, 39, as two of his four children...