In the 1970s John concluded that all buildings should be designed to need the least amount of energy in the first place. They should be passively designed to be energy defensive. For energy needed, alternative sources were implemented: examples include sun, water storage, wind, natural ventilation, thermal mass, evaporative cooling, waste heat recapture, shading and day lighting. Conventional sources of energy were employed as a last resort. Energy efficient buildings included the award-winning Clark Library at San Jose State University and the California Farm Bureau Federation Headquarters in Sacramento which won the national Owings-Corning and Department of Energy awards in 1981. Other similar projects include Nevada National Bank Headquarters in Reno, Koret Health and Recreation Center at the University of San Francisco, Batmale Hall at City College of San Francisco, and the US federal government's 600,000 square foot office complex in the Nevada desert. The firm created energy manuals for existing buildings for Bank of America, Pacific Gas and Electric and historic buildings in Shanghai The energy-defensive buildings consumed 18,000 to 38,000 btus/sq ft/yr - only 33 to 68 per cent of energy use standards proposed at the time. Energy savings paid for the entire construction cost of the buildings within twenty years.