Coffee fuels millions of people’s mornings, but like other fuels it also comes with its own unique environmental issues. Coffee is one of the globe’s largest agricultural commodities, with about 8bn kilograms (more than 16bn lbs) grown annually worldwide. That’s a lot of coffee – and a lot of leftover coffee grounds, most of which ends up in landfills or, in a best-case scenario, as a soil conditioner in someone’s garden.
Many people seem to like the idea of turning something they throw out daily into a useful commodity. Companies such as Starbucks and Nestle, for example, are already putting used coffee grounds to work, while researchers believe that oil from coffee grounds could end up contributing tens of millions of liters of biodiesel to the global fuel supply.