Water efficiency linked to ‘surprisingly large’ energy savings in new study

August 25, 2016

In every green building project, designers put countless hours into developing a plan that not only limits the structure's demand on the grid but also reduces its reliance on natural resources. New research from the UC Davis Center for Water-Energy Efficiency now shows just how linked those two goals may be, finding reduced water usage can lead to substantial cuts in both energy usage and greenhouse gas emissions

To make this connection, researchers analyzed the effect of urban water usage limits mandated to counter California's ongoing drought. By reducing urban water usage by 25 percent between June 2015 and February of this year, the state saved about 922 gigawatt-hours of energy – enough to power 135,000 homes for an entire year, the LA Times reported. Plus, it saved an additional 220,000 metric tons of greenhouse gas emissions, equivalent to taking about 50,000 cars off the road, according to GreenBiz. 

"Reduced water usage can lead to substantial cuts in both energy usage and greenhouse gas emissions."

In fact, during peak summer months reducing water consumption alone saved as much energy as most other major energy efficiency programs in California combined, the LA Times reported. Further, water-related savings came with just one-third of the price tag compared to other programs. 

While industry professionals have long linked water usage with energy consumption, the UC Davis analysis makes clear just how massive the opportunity for savings truly is. 

"The numbers were surprisingly large for those of us who have been in this field for some time now," said Max Gomberg, conservation manager for the state water board, according to the LA Times. "I was pleasantly surprised at the magnitude of the action."

Turning insight into action
So, with this potential for savings in mind, what can we do to limit our water usage going forward? The Natural Resources Defense Council (NRDC) outlined a number of water-saving strategies that can be implemented throughout the state, from improving efficiency in urban and agricultural settings to improving reuse and rainwater collection systems. 

Of these methods, improving urban residential and commercial efficiency is one of the most important. Urban businesses and homes accounted for about 20 percent of the state's overall developed water use between 2001 and 2010, according to the NRDC. Based on the Council's analysis, commercial water usage could drop by anywhere from 30 to 60 percent by simply adopting up-to-date water-saving technologies and best practices. Similarly, relatively small improvements, such as repairing leaks and choosing more efficient appliances, could bring residential water usage down by as much as 60 percent. Most importantly, achieving these savings is entirely feasible with technology that is already widely available today.