The bathyscaph is a deep water submarine used to explore the very lowest parts of the ocean. It is electrically powered. Once at the bottom, if the batteries or electrical system fail the best outcome would be for the sub to return to the surface. The designers made this outcome occur by holding the ballast in place with electromagnets. When power is lost, the ballast drops off automatically and the sub starts its ascent.
11 Ingenious Solar Projects Impacting the Developing World
The Water-Scraper Designed by Malaysian architect Sarly Adre bin Sarkum. The building would generate its own power using wave-power, solar energy and wind power, and has its own farms, including aquaculture and hydroponics farms.