Potential developers for a 500MW pumped hydropower energy storage facility at a reservoir in San Diego have until mid-September to respond to a request for proposals (RfP). Energy-Storage.News reported back in late April that San Diego Water Authority was gauging interest from industry in executing the vast project, which would net revenues that could lower water rates for consumers in California, while assisting in the integration of renewables, particularly solar PV. The project would be jointly owned by the Water Authority and the City of San Diego, which owns the site where the facility would be built.