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Nonprofit Teams to Produce Solar-Powered Coffee

By From the Lowell Sun

Who came up with the idea that grinding the pits of bitter coffee cherries, putting them through water and slurping the black liquid might be fun?

You wonder about it when you hear just how many steps it takes to produce a bag of coffee. Plucking cherries by hand, taking the skins off, fermenting, raking and drying beans -- the list goes on.

But perfecting the process is now coffee producers' pride. With the world hooked on coffee, plantations around the world are busy firing up bean-drying machines, throwing piles after piles of wood into the furnace.

Most coffee producers use electric/wood-fired driers based on an 80-year-old design, said Rich Trubey, program developer at Mesoamerican Development Institute (MDI), a nonprofit organization based at UMass Lowell. These machines eat up enormous electricity and lots of firewood -- so much so that a half-inch square foot of rain forest disappears for every cup of joe that you sip, even an organic one.

"It's kind of a hidden story of the coffee industry," Trubey said.

But in the mid-1990s, the MDI -- which helps increase the efficiency of food production in rural Latin America through use of renewable energy -- teamed up with Cooperative Montes de Oro, a cooperative of 300-plus farmers in Miramar, Costa Rica, and installed three units of 25-foot-tall "solar coffee drying tower" developed by the MDI.

The tower is a hybrid, designed to use both solar heat and propane-like gas made from corn husks. During the day, the water goes through pipes attached to 16 flat-plate solar thermal collectors, picking up more and more heat as it travels from one panel to the next. It eventually reaches boiling temperatures before flowing into a hot water tank, which then sends forced hot air into the towers' chambers. When the sun goes down, the gas tank kicks in to keep the water hot.

The MDI had all parts of the towers manufactured in Massachusetts and New Hampshire. The tower uses just 20 percent of electricity that a conventional drying machine requires, Trubey said. It has reduced the cost of drying 100 pounds of coffee from $3.50 to 40 cents.

This carbon-neutral, organic, fair-trade coffee to Red Barn Coffee Roasters in Upton, which roast the beans and packs them in bags that carry the brand name of Café Solar. Market Basket began carrying Café Solar in 2005, and the one-pound French and medium roast bags are currently sold for $7.99 each.

This solar system protects not only trees, but also migratory birds that rely on the forest. The MDI and the Cooperative Montes de Oro received the U.S. Forest Service's 2009 Wings Across the Americas Award in March.

Coffee beans are a fussy fruit. African coffee farmers used to dry them on a porch under the sun, but this is labor-intensive and beans can grow mold easily. So producers rely on wood-fired machines.

The industry has been changing, though, adopting different sustainable practices. If done right, plantations can increase forest biodiversity, Trubey said.

For information on Café Solar, visit

Have green story ideas? Hiroko Sato can be reached at