PlusEnergy is a term used in building design to describe a structure that produces more energy than it uses. The term was coined in 1994 by Rolf Disch when building his private residence, the Heliotrope as the first PlusEnergy house in the world. Disch then went on to refine the concepts involved with several more projects built by his company Rolf Disch Solar Architecture in order to promote PlusEnergy for wider adoption in residential, commercial and retail spaces.