EL MONTE, CA — The Cathay Bank Corporate Center, a renovated building designed to sharply reduce energy and water use, is now adding a solar photovoltaic system to supply about a third of the site's electricity.

PermaCity Solar began construction this week on the project to build a 432.5 kW PV system that will canopy new carports at the bank's building in El Monte.

The canopies will feature 2,128 solar panels, which are sourced from PermaCity Solar's partner Schüco.

The PV system is expected to generate 695,181 kWh annually, cut energy costs by 40 percent and save the banking firm about $9,000 a month.

The system also will prevent an estimated 494 tons of CO2 from being released into the atmosphere, according to PermaCity Solar President and CEO Jonathan Port.

Port's company designed the carport PV system in collaboration with Gensler, the architect for the seven-story repurposed building that houses the bank's corporate offices, and renewable energy consultancy EcoMotion.

Cathay Bank acquired the 102,548-square-foot building four years ago this month. Rather than raze the structure, Gensler recycled it. (Before and after images are below.)

Gensler's design strategy included hanging a high-performance glass curtain wall on the exterior. Inside, the siting of workstations, conference rooms and other occupied areas, lighting systems that take advantage of natural light, and other energy and water-saving measures -- including use of low-flow and waterless restroom fixtures -- all support a building design that reduces environmental impacts.

Now showcased among Gensler's "Green Keepers" projects, the Cathay Bank Corporate Center uses 31 percent less energy, 47 percent less interior lighting and 65 percent less water than a non-green building of comparable size.

The solar-canopied carports are an extension of the efforts to lighten the site's environmental footprint. At night, LEDs powered by PV system will light the carports. The installation project is scheduled to be complete in September.

Established in 1962, Cathay Bank is the oldest Chinese American bank in the United States. Its holding company, Cathay General Bancorp became the largest Asian American banking corporation in 2003, and in 2008 was ranked the 9th most efficient bank holding company among the largest 500 by American Banker magazine.

Images courtesy of Cathay Bank, Gensler and PermaCity Solar.