SunPower solar PV system switched on at HP facility in San Diego

SAN DIEGO--As blustery Santa Ana winds kicked up on a blue-sky Southern California day, officials from Hewlett-Packard, SunPower, GE Energy Financial Services, and local and state government dedicated a new 1.1-MW solar photovoltaic rooftop power system today at HP's imaging and printing R&D facility in Rancho Bernardo.

The SunPower T10 solar roof tile commercial roof system is installed on five different HP rooftops, covering approximately 200,000 square feet of space, according to HP's project manager, Kevin Cowen. HP decided to use Evergreen Solar 190- and 180-W panels rather than SunPower units for the system, he says, accepting lower per-module conversion efficiencies because of cost considerations and what he called a corporate edict to have "no out-of-pocket expenses" on the project. 

HP also kept costs down by entering into a power purchase agreement rather than acquire the system itself, choosing to buy competitively priced electricity from GE Financial Energy Services under its SunPower Access program. Under the terms of the deal, HP owns the renewable energy credits and green benefits of the system, which it may retire or sell.  

With a rated capacity of 1172-KW-peak and an expected annual energy production of 1,651,000 KW-hr, the nonpenetrating rooftop system will provide 10% of the facility's power load, Cowen said. The installation team chose four Xantrex 250 inverters to help run the system. 

The system took about two months to install. Cowen said that PV panels and other components were lifted by crane onto the various rooftops for set-up over the course of six weekends, then the DC and AC wiring was laid in and the inverter spaces excavated and units installed near the various buildings.

During remarks at the dedication ceremony, SunPower CEO Tom Werner (shown in photo above on one of the rooftops) noted how the HP system is one of the biggest of its kind in San Diego County. He also mentioned a program that his company has started with HP, under which company employees can get SunPower PV systems put on their residences at reduced rates, noting that 600 HP workers have chosen to take advantage of the arrangement so far.

In an exclusive interview with PV-Tech at the event, Werner also commented on the impact of the recent extension of the eight-year investment tax credit on the US solar industry.

"At Sunpower, we call it the solar trifecta—it’s created three unique new markets for solar in America," he said. "One is utilities, they weren’t in the last ITC, and that turns out to be huge. We announced two utility agreements this summer, one in San Luis Obispo with PG&E and one with Florida Power and Light.

"If you’re looking at the commercial market, it's an eight-year market, so companies like HP that have multiple sites, they can plan it out over an eight-year horizon as they add solar to their sites.

"Then residential is uncapped at 30%, so now you have a nationwide program. For a company like SunPower located in the States, which serves all three markets, it’s just phenomenal." 

-- story and photos by Tom Cheyney