I recently noted that Hawaii has enacted a law that requires all new homes to install solar water heaters. Eventually, Hawaii may have as many water heaters as Israel, where 90% of homes have solar water heaters installed. When viewed from above, the Jerusalem often glitters with the shine of the thousands of solar heaters that adorn rooftops.
These heaters were first installed when the country experienced a fuel supply crisis in the early 1950s. The government responded by severely restricting the times when water could be heated. Israelis in turn responded by purchasing huge quantities of solar water heaters. By 1983, 60% of the population heated their water with the sun. A law was eventually passed requiring the installation of solar water heaters.