Approximately a year after reopening, the Berkeley Public Library’s West Branch has been deemed the first “net zero” energy library in the state.

After collecting a year of data since its opening in December 2013, the West Branch has been officially certified to be producing more energy than it uses. From the conception of the project, the planners’ goal was to expend zero net energy, according to Alice LaPierre, the city’s energy efficiency coordinator. The library’s solar panels produce on average 500 kilowatts per hour more per month than the building uses — enough energy to power two houses for a year.

“We are really thrilled to have Berkeley Public Library’s West Branch be the first net zero library,” said Jeff Scott, the director of library services. “It truly is in the spirit of Berkeley for our library to be energy efficient.”

The library’s zero energy expenditures can be attributed to large windows and long skylines, solar panels and ventilation, according to a press release from the library.

“The No. 1 step to accomplish a net zero facility is controlling solar gains,” said Edward Arens, an architecture professor at UC Berkeley.

During the library’s reconstruction process, Arens visited the West Branch and spoke with one of the main designers on the project. According to Arens, the building has a ventilation system that encourages good air flow, as well as efficient lighting and many solar collectors that offset the electricity needed for computers, fans and other equipment.

West Branch was rebuilt after the passage of Measure FF, which provided bonds not exceeding $26 million that focused on renovating the city’s libraries. The measure’s aims included building more accessible and seismically safe facilities.

“The redesign of our public libraries was initiated by the city, but we wanted to go beyond that,” said Deirdre Cerkanowicz, a library specialist.

Libraries and city leaders also hope that the West Branch will be awarded platinum status, the highest rating offered by the Leadership in Energy and Environmental Design, a green certification program.

Since 2000, the city of Berkeley has been initiating energy efficient projects, such as using solar hot water systems for Dona Spring Animal Shelter and West Campus Swim Center, according to LaPierre. Upcoming projects include modifying the garage on Center Street to become net zero and instituting electric car charging stations.

Since reopening, the West Branch has seen an uptick in the usage of its various programs.

“The redesign of West Branch has brought a new life and energy into our branch,” said Suzanne Olawski, Berkeley Public Library’s deputy director. “I’m quite proud of the branch bond program and building a new facility that is accessible and seismically safe … and of the community for supporting our libraries.”