Conserve Energy to Save Water

Newsha Ajami is the director of urban water policy at Stanford’s Water in the West program and the Engineering Research Center-ReNUWIt.

Updated June 30, 2014, 6:09 PM

Chances are you've washed your hands a few times today. Have you ever considered the energy footprint of this ritual? Or how much water is needed to power your lights, computers and cars?

Water is an integral part of energy development and production. It is used to refine and process fuel, produce electricity and cool power plants. Similarly, energy is just as necessary to every step of our water-use cycle: it is used for water extraction and distribution, as well as wastewater collection and treatment.

Have you ever considered how much water is needed to power your lights, computers and cars?

For example, in California, nearly 20 percent of the state’s electricity requirements go toward water. Much of it is either used to move water across the state through a sophisticated distribution system, or for the treatment of water and wastewater. Thirty-two percent of California’s natural gas consumption — excepting gas from nuclear power plants — goes toward water, as well. Much of it is used for heating water in homes. While there is limited data available on energy-related water consumption in California, in the United States the energy sector — including biofuels, thermoelectric and fuel production — is the second-largest water consumer at 14 percent, second to agriculture at 71 percent.

But this usage is not sustainable. California is currently confronted with a number of water and energy challenges, including an extensive drought, rising energy costs and a growing realization that cheap water and energy sources are limited. The immediate and long-term effect of climate change on the state’s water and energy resources will exacerbate these challenges.

Plus, our future water supply portfolio is likely to be more energy intensive. New and alternative water sources — such as water recycling and desalination — require more energy than it takes to access traditional surface and groundwater sources. Groundwater extraction is becoming more energy intensive because of declining groundwater levels. Stricter water quality standards are increasing the amount of energy needed for water treatment processes and our aging, leaky infrastructure is an issue, too.

Likewise, new energy and fuel production options have become more water intensive. Unconventional oil and gas production methods such as hydraulic fracturing have significant implications for local and regional water quality and quantity. Bioenergy consumes water at various stages of production (including irrigation for crops) and also has impacts on water quality and quantity. In addition, the expansion of nuclear energy and its resultant high-temperature discharge water can significantly affect regional water availability and quality.

To confront the intersecting problems of energy and water, states like California must coordinate more efficient and complementary systems.

We should be pursuing cleaner energy and streamlined approaches to conserving water in order to truly safeguard our water supply. Water conservation, leak prevention, rain and storm water capture, graywater reuse and pollution control are all simple measures that could enhance our water security without putting extra pressure on the water resources, all while improving our energy footprint. Cost-effective cross sector investments are necessary for states like California to reach a sustainable water-energy equilibrium that meets current and future demand.