Most of us take for granted turning the faucet and filling a cup with cold water to drink on a hot summer day. The reality is the transport, treatment and distribution of water all requires energy. Water utilities have the opportunity to save a significant amount in costs while also improving energy efficiency and reducing pollution by adopting water conservation programs.  And when we save water, energy is saved as well.

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Source: National Conference of State Legislatures

Currently, numerous companies only have leak-detection programs in place to reduce the amount of wasted water. This is important considering the average water loss in the water system is 16%. Furthermore, leaking pipes result in additional energy to deliver water to its destination. There is a very limited set of utility companies that have adopted water saving technology or other conservation techniques such as water audits.  Energy costs can constitute 25–30% of total operation costs for water and wastewater utilities. By installing water saving pumps and motors, utility companies can lower these significant costs while also improving their services.

The energy intensity of a water system varies based on several factors according to a survey of water companies conducted by the National Association of Water Companies (NAWC) and the American Council for an Energy-Efficient Economy (ACEEE) including the distance water travels in the system, the water source, and the size of the water utility. As a result energy consumption can also vary from system to system. It is important that water utilities better understand their current state of energy consumption so they can make improvements on it. One of the best ways to do this is to have an energy audit. An energy audit provides water utilities with a range of options to improve energy performance. Water utilities may also make operational improvements requiring the enactment of a strategy to regularly monitor energy usage within the water and waste-water infrastructure.

Energy is also required to collect, treat, and dispose of waste-water. In 2010, the U.S. water system consumed over 600 billion kWh, or approximately 12.6 percent of the nation’s energy according to a study by researchers at the University of Texas at Austin. The study found water systems use about 25 percent more energy than is used for residential or commercial lighting in the U.S.

The water energy nexus is mutually dependent relationship. Not only is there a significant amount of energy required in transporting water, but there is also large quantities of water needed to generate energy. This includes fossil fuels, biofuels, and non-conventional fuels. In the United States, generating energy consumes 20% of the water not used by agriculture. As the demand for energy in the United States continues to rise, there will also be a mandated increase in water consumption, an important  concern that will need to be addressed going forward.