ZNE is a term describing buildings, homes — even communities — that generate as much renewable energy onsite as they use annually. California law now calls for 50% of existing commercial buildings to be retrofitted to ZNE by 2030.
“The Point Loma/Hervey Library will remain open throughout the zero net energy renovation process, although patrons may notice work going on in different parts of the building,” said Christine Gonzalez, branch manager, Point Loma/Hervey Branch Library. “As one of the first City buildings to be converted to ZNE, we’re excited to be a model for sustainability and the move toward 100% renewable energy.”
The other two libraries in the ZNE rollout are Serra Mesa-Kearny Mesa Library and Valencia Park/Malcolm X Library.
All three libraries already have solar photovoltaic systems to generate energy. Converting to ZNE will require the installation of additional technologies including LED lights and new lighting sensors; heating, ventilation and air conditioning (HVAC) control devices; building automation systems; and energy-monitoring equipment.
“The City of San Diego is working to transform our municipal building stock to drastically reduce energy consumption, energy costs, and greenhouse gas emissions,” said City chief sustainability officer Cody Hooven. “These ZNE library projects are proving that it can be done and will serve as an example for future deep energy retrofits of City facilities. We’re excited to bring clean energy resources to these communities and pave the way for the City’s clean energy future one building at a time.”
The start of the retrofitting of Point Loma/Hervey is set to begin at the end of February.
Shannon Sales, an associate City engineer on its sustainability team, explained why libraries were chosen for the ZNE project.
“We wanted a place where people go that would be a good test case,” said Sales, noting libraries are designated “cool zones” where the public can take refuge in especially hot times. “We also wanted a place where its solar panels are visible, so the community can see that steps are being taken to achieve zero net energy making the buildings more efficient.”
Amplifying the definition of net-zero energy, Sales said those buildings “must produce more energy annually than they consume. We figure that Point Loma Library annually produces the energy of 35 homes per annum.”
Once ZNE retrofitting is complete, the Center for Sustainable Energy will begin monitoring energy usage to determine if the buildings will achieve ZNE, or if additional improvements are required.
Sales said there will be an “interactive dashboard display” in Point Loma/Hervey Library so people can see how much energy is actually being consumed adding, “We can adjust and tweak the settings to make it run as efficiently as possible. “This program is a pilot right now, but it can be replicated citywide in other retrofitted buildings.”
The project is being funded by a grant from the California Energy Commission in cooperation with SDG&E.
The ZNE program is part of the City’s Climate Action Plan, approved in 2015, which calls for eliminating half of all greenhouse gas emissions in the city and aims for all electricity to be from renewable sources by 2035.
Recently, Mayor Kevin Faulconer released the 2019 Climate Action Plan Annual Report, which shows the City is ahead of schedule in meeting its clean-air goal.