Carlsbad Desalination Plant Supports Statewide Energy Conservation Efforts

August 18, 2020

Cutting-edge technology and local control give plant flexibility for intermittent operational reductions during peak-use periods

To support statewide emergency energy conservation efforts, Poseidon Water and the San Diego County Water Authority are temporarily reducing water production at the Claude “Bud” Lewis Carlsbad Desalination Plant.

While the plant uses less than 1% of peak energy demand in San Diego Gas & Electric’s service territory, Poseidon and the Water Authority are committed to supporting electrical reliability while ensuring continued delivery of safe and reliable water supplies.

The Carlsbad plant is also the first major water infrastructure project in California to eliminate its carbon footprint. It eliminates the need to transport water from Northern California to the San Diego region, offsetting approximately 190,000 megawatt-hours of electricity and 68,000 tons of carbon emissions each year. The plant also uses energy recovery devices that save an estimated 146 million kilowatt-hours and reduce carbon emissions by 42,000 metric tons every year.

“This partnership by the Water Authority and Poseidon is another reminder of the value of the cutting-edge technology and local control at the Carlsbad plant,” said Jim Madaffer, chair of the Water Authority’s Board of Directors. “Operations are flexible and the technology is nimble, so production can be ramped up and down in response to local needs.”

The Water Authority is also working with its 24 member agencies to reduce other power demands during the heatwave by closing offices early and shifting energy-intensive pumping to off-peak hours. In addition, the Water Authority is running its Lake Hodges Pumped Storage Facilities to generate up to 40 megawatts of on-demand power, helping meet temporary peak demands.

The Carlsbad Desalination Plant is the largest, most technologically advanced and energy-efficient desalination plant in the nation, and it has produced more than 62 billion gallons of drinking water for San Diego County since it began operations in December 2015.

Starting Monday, the plant ramped down operations, making an additional 8 megawatts of power available for other uses. If more load reductions are necessary over the next several days, additional curtailment may be considered at the plant.

“This is an example of how desalination plants can help contribute to energy reliability, in addition to water reliability, by taking appropriate action to increase the available energy capacity during the extreme heat event,” said Poseidon CEO Carlos Riva. “After the past several months in particular, we’re no strangers to crisis planning and we’re proud to do whatever we can to help our region address the current energy shortage.”

For more information, go to the plant website,, or to the Water Authority’s website,

  • The San Diego County Water Authority sustains a $268 billion regional economy and the quality of life for 3.3 million residents through a multi-decade water supply diversification plan, major infrastructure investments and forward-thinking policies that promote fiscal and environmental responsibility. A public agency created in 1944, the Water Authority delivers wholesale water supplies to 23 retail water providers, including cities, special districts and a military base.

    Media Contact Information

    Grace Sevilla

    Phone: (619) 855-5135