Net Positive Energy Performance at Berkeley Library Looks Promising

West Berkeley Public Library, Berkeley, CA  |  Credit: Mark Luthringer

The West Berkeley Public Library was aiming to be the first library in California to achieve net zero energy (NZE) performance when it opened nearly a year ago in December 2013. After 11 months of operation the building is on track to achieve that goal and more. During several months the library had net positive energy performance, meaning the 175 onsite photovoltaic panels produced more than the building consumed, according to data collected.

The library’s predicted EUI as designed is 25 kBtu/sf/year, a 76% reduction from the national average EUI for this type of building, It utilizes natural ventilation for cooling and a solar thermal system to heat water for the radiant floor. Daylighting and shading strategies as well as optimal window-to-wall ratios minimize heat gain and the need for electric lights.

When the time came to rebuild the library, the city awarded the project to architecture firm Harley Ellis Devereaux, the only firm to propose a ZNE building. The 9,399-square-foot project is now helping to advance the city’s Climate Action goal of reducing greenhouse gas emissions (GHG) by 33% from year 2000 levels.  The design and construction process was supported by Pacific Gas and Electric Company with funding and modeling under the utility’s ZNE Pilot Program.