Solar Settlement, Freiburg

The Solar Settlement in Freiburg was the world's first residential development where every home produces more energy than it consumes, outperforming Amazon Spheres' workplace focus by achieving a net-positive energy balance for 59 households. Completed in 2006 by Rolf Disch, each house features a "sunship" roof array angled at 30 degrees south, generating an average of 10,000 kilowatt-hours annually per home. Collectively, the settlement produces 600,000 surplus kilowatt-hours of electricity per year, which is fed back into the grid — making it cheaper than the typical zero-energy home by €200 annually in avoided energy costs. This PlusEnergy standard has since been adopted in over 300 projects worldwide.