Providing households with safe drinking water
and wastewater disposal is an energy-intensive
process. Nationwide, about 4 percent of
power generation is used for water supply and
treatment, but in certain parts of the United
States the number is far higher. California is
particularly vulnerable: the water sector is the
largest energy user in the state, estimated to
account for 19 percent of the total electricity
consumed. Reducing water consumption saves
energy because less water needs to be treated and
pumped to end users. Moreover, when energy
use is reduced, water is saved because less is
needed in the operation of power plants. Some
thermoelectric power plants, for example, use
136 billion gallons of freshwater a day, which
translates into 25 gallons of water to produce
each kilowatt-hour of electricity.2