Combining two of Italy’s delights — coffee and sunshine — a couple of engineers in Rome have created an environmentally friendly way to roast coffee beans without electricity or gas. Antonio Durbe and Daniele Tummei have spent almost six years building and perfecting their sunlight coffee roaster.

The result is a system that needs a piece of land about the size of half a tennis court and sunny weather to roast up to 50 kilograms (110 pounds) of coffee an hour. The plant is run entirely by energy from the sun. Sunrays are concentrated by a set of mirrors on a coffee roaster and even the few electrical parts are powered by a small solar panel.