The San Francisco Public Utilities Commission plans to begin construction on the “Bay Corridor Transmission and Distribution” project early next year. The work will involve a stretch of Illinois Street, from 23rd to 16th streets, as well as smaller portions of Terry A. Francois Boulevard, 22nd, 20th and Mariposa streets. It’s expected to take a year to complete, financed by revenue from SFPUC-owned hydropower generated from the Hetch Hetchy Reservoir.
“The project is in the preliminary stages of putting in a high voltage clean energy transmission line,” said Charles Sheehan, communications manager, SFPUC. “It’s for commercial users who use a fair amount of energy, such as medical and biotech or municipal clients who are large energy users.”
California’s Clean Energy and Pollution Reduction Act of 2015 mandates that the state increase the proportion of its electricity derived from renewable sources, to 33 percent by 2020, 50 percent by 2030. The City has its own, more ambitious, renewable goals: 50 percent by 2020; 100 percent by 2030. Roughly 44 percent of the City’s electricity demand is currently meet by renewables.
Greater use of SFPUC’s hydropower within the City would contribute to San Francisco reaching its renewable electricity goals. However, given that all of SFPUC’s hydropower is currently used, either in or outside of San Francisco, increased reliance on this source within the City may not directly create any additional clean energy resources to meet state mandates, and won’t contribute to overall national emissions reductions.
SFPUC’s primary function is to provide water services to San Francisco residents and businesses, as well as the nearby counties of San Mateo, Alameda and Santa Clara. According to SFPUC literature, the Hetch Hetchy Power System is the backbone of the City’s clean energy portfolio. Hetch Hetchy water produces 93.5 percent of SFPUC’s power mixture; the rest is generated by smaller hydroelectric facilities, solar, wind, and geothermal. In addition, 80,000 wet tons of biosolids discharged in San Francisco annually is “digested,” releasing methane, which is used to generate electricity.
SFPUC’s renewable electricity supplies are used to power public facilities and businesses, including Muni, hospitals, schools, and residents and businesses located in the San Francisco Shipyard. Cruise ships also access the renewable electricity at shoreside charging stations. In 2014, the San Francisco Board of Supervisors approved legislation to enable SFPUC to sell electricity directly to City residents, replacing power that would otherwise be provided by Pacific Gas and Electric Company.
“Hetch Hetchy power is truly zero emissions energy,” Sheehan commented. “The 100 percent greenhouse gas-free energy represents 17 percent of the City’s energy needs. The airport is our biggest client; the planes are plugging into Hetch Hetchy water. You can’t be clean energy if you’re plugging into electricity produced from coal.”
At San Francisco International Airport, electricity is used to power airplane lights, controls, backup components, and in some cases, enables passengers to charge devices at plugs located adjacent to their seats. According to the California Energy Commission, four percent of California’s electricity needs are supplied by coal-generated power, most of which is consumed in the southern part of the state.
The Bay Corridor transmission line will principally serve customers in District 10, which, according to Sheehan, includes neighborhoods that’d historically been under the shadow of the polluting Potrero and Hunters Point power plants. The work will mainly involve putting in a conduit, or tube, through which the high voltage transmission line will run. SFPUC will coordinate with PG&E to connect the transmission line to the investor-owned utility’s Illinois Street substation. However, Sheehan stressed that the line will belong to SFPUC, which’ll interface directly with hydroelectric customers.
“In addition to putting in the conduit, we’ll also be installing fire suppression capabilities for the City,” added Sheehan. “Combining the work saves money and time. Hydrants, four times the size of regular hydrants that can deliver high pressure water supplies, will be added along Mariposa to Terry Francois at South Street.” The Auxiliary Water Supply System, also known as the “Emergency Firefighting Water System,” is funded by Earthquake Safety and Emergency Response bonds approved by voters in 2010 and 2014.
The work will also include private development entities that’re undergrounding utilities in the area, such as the Mission Bay Development Group, which is constructing the Mission Bay South project, located between Mission Creek, Mariposa, and Seventh streets and the Bay. Coordination between SFPUC and other entities will allow streets to be excavated to accommodate multiple projects.
“There will be a 72-hour notice for parking,” offered Steve Kech, public relations officer, SFPUC. “Also, barriers will be put in place for rerouting traffic. Most of the work will be in the parking strip next to the sidewalk.”
According to SFPUC representatives, work will be done one block at a time to minimize traffic congestion, preventing entire streets from being closed off during construction periods that’ll only occur during daytime hours. The goal is to allow traffic flow in both directions where construction is being conducted. The Commission plans to issue notifications on Nextdoor, send mailings, and attend neighborhood meetings to inform community members about the work.
According to Sheehan, the Bay Corridor Transmission and Distribution high voltage power line will convey Hetch Hetchy hydroelectricity, as well as power from smaller hydroelectric facilities. “It’s about building the City’s clean energy infrastructure, and doing sewer and water work as well,” said Sheehan. “The true value of the project is that by offering clean, Hetch Hetchy waterpower to our customers, we’re lowering the City’s overall greenhouse gas emissions.”