A High-resolution Energy Intensity Analysis of the Otay Water District System.

摘要

The water sector is an emerging target for energy efficiency efforts in the State of California. Energy is embedded in water from pumping, treatment, end uses, and wastewater treatment. The water sector accounts for 19.2 percent of statewide electricity consumption, with 7.7 percent attributed to conveyance, treatment, and distribution infrastructure. Energy savings can be realized through water conservation. A clear, defensible calculation of energy intensity (EI) is required to effectively harness this and allocate energy efficiency dollars.;This study is focused on the Otay Water District in San Diego County and included upstream energy contributions along the San Diego Aqueduct, operated by the San Diego County Water Authority. The EI for all pressure zones within the Otay Water District was calculated. Several trends were noted. Temporally, both EI and water consumption followed seasonal trends. Water consumption peaked in the summer months while EI peaked in the late winter. Spatially, as expected, EI increased through the system with elevation as more pumping was needed to deliver water.;Using the results, pressure zones were identified as potential targets for conservation programs. Pressure zones that consumed the largest amounts of energy and water were identified as targets for programs to conserve energy through water conservation. Zones consuming large volumes of water but relatively little energy are targets for programs solely for water conservation. Pressure zones that consumed low volumes of water but high amounts of energy are targets for energy efficiency upgrades. The remaining zones, while not major consumers of water and energy, are still targets for general conservation.