1909-1918: New Solar Water Heater Design Dramatically Increases Length of Time Water Remains Hot, Sells Well

Despite the initial success of the “Climax” solar water heater (see 1891), consumers are dissatisfied with a major drawback of the heater: its inability to keep the water it heats hot for more than a few hours. Inventor William J. Bailey of the Carnegie Steel Company separates the solar heater into two components: a heating element exposed to the sun and an insulated storage unit kept inside the home. Bailey’s invention allows families to have solar-heated water day and night, and even into the next morning. The device keeps water in narrow pipes instead of a large tank, allowing the water to retain its heat longer and for less water needing to be exposed to the sun at any given time. Bailey calls his invention the Day and Night, and by 1918 sells over 4,000 of the heaters. [California Solar Center, 2001; US Department of Energy, 2002 ]