What's green, brown, and powerful? Compost, at least in Boston.

Beantown is planning an urban composting facility that will collect yard waste and other compostable plant material, bring it to an indoor facility, and use the methane and heat that decomposition produces to create electricity and high-quality fertilizer. Planners forecast that enough electricity to light 1500 homes will be produced by the plant when it goes online, as well as enough heat to run on-site year-round greenhouses and sell excess fertilizer.

So, in exchange for something worthless -- leaves, banana peels, and apple cores -- Boston gets locally produced food, electricity to help offset the cost of the facility, and a decreased greenhouse footprint, merely by taking advantage of heat and methane that was once wasted.

This is really one of those "so smart, the rest of us feel dumb for not thinking of it" sorts of schemes that we EnviroWonks can only hope more cities begin to adopt. How much yard waste, veggie trimmings, spoiled leftovers, and past-expiration food do we all throw away? Perhaps more significantly, how much compostable waste do city parks, supermarkets, farms, packing facilities, restaurants, and the like produce?

It seems to us that there's a lot of energy-rich trash we're throwing away, and we can only applaud Boston for realizing its true value. And maybe, with a little push from the rest of us, we can convince our hometowns to see the wisdom in urban composting plants.