As San Diegans start to crank up their air conditioners, the city and the San Diego County Water Authority are developing a way to store energy by using water. Water officials said it’s expected to save ratepayers money in the long run, according to a May 4 report by the ABC-TV affiliate KGTV San Diego. The city and authority want to build an energy storage facility at the San Vicente Reservoir, about 25 miles northeast of San Diego.