查看文章

Life-cycle air emission effects of supplying water are explored using a hybrid life-cycle assessment. For the typically sized U.S. utility analyzed, recycled water is preferable to desalination and comparable to importation. Seawater desalination has an energy and air emission footprint that is 1.5−2.4 times larger than that of imported water. However, some desalination modes fare better; brackish groundwater is 53−66% as environmentally intensive as seawater desalination. The annual water needs (326 m³) of a typical Californian that is met with imported water requires 5.8 GJ of energy and creates 360 kg of CO₂ equivalent emissions. With seawater desalination, energy use would increase to 14 GJ and 800 kg of CO₂ equivalent emissions. Meeting the water demand of California with desalination would consume 52% of the state’s electricity. Supply options were reassessed using alternative electricity mixes …