Caffeine fuels many of our days, but an even bigger energy source may be the grounds themselves. A new waste-to-gas technology, originally developed by NASA for powering lunar bases, is being adapted to turn enormous amounts of coffee waste (paper, burlap sacks, plastics, and biomass) into clean energy.
Green Mountain Roaster, a supplier to multinational corporations such as Starbucks and McDonald’s, is taking the first steps to demonstrate that the concept works with its own waste. "Syngas," a molecular cousin of natural gas which can burned to produce highly efficient electricity and heat, or used to power vehicles, is created by breaking down raw biomass into useful fuels. The basic concept, known as "torrefaction," is not all that different from turning any "bulky, water-saturated material," raw biomass, into combustible fuel perfect for coal-fired power plants.
It fact, it’s very similar to roasting coffee beans. Material is heated to around 572 degrees in an airless chamber. The dry, energy-rich powder (similar to the creation of biochar) can be made from plant materials such as willow, poplar, perennial grasses, and wood waste from sawmills, according to researchers at the U.K.'s University of Leeds.
The process still has kinks. One major one is that the torrefied powder can explode in storage. There is not a cheap, existing distribution network enjoyed by oil, gas and coal. But the U.S. Environmental Protection Agency has already targeted millions of acres of brownfields and abandoned industrial sites for growing energy crops on marginal land to usher in the day when biomass will not be waste, but energy.