Net-zero energy commercial
DPR’s team of experts set its sight on transforming a dilapidated business park into a netzero energy use, natural systems demonstration project.
In 2009, DPR Construction Company, Inc. (DPR) decided to invest in a company-owned regional headquarters (HQ) in San Diego, California. It had been leasing its HQ space, which limited its ability to retrofit and redesign it. DPR discovered an abundance of speculative commercial buildings near the end of their useful lives in its community. These buildings have less optimal building systems that risk being a burden to their operators; however, DPR recognized an opportunity. It could reuse an existing building structure, because there are many ways to overcome an aging building’s potential inefficiencies in mild, coastal climates.
The project would embody DPR’s corporate leadership and culture, which affirms a respect for the individual and a belief that together they can change the world and nurture an atmosphere where employees, clients, partners and the environment are all valued assets.
DNV KEMA joined DPR’s project team as an expert in energy efficiency and passive system design, which uses natural cross-ventilation to cool and daylight harvesting tactics to reduce electricity use. DNV KEMA worked with the architects, mechanical and electrical professionals, and DPR employees to integrate these features throughout the 24,000-square-foot building and its exterior area. Key features include
> Optimization of energy performance through maximized natural ventilation, daylight harvesting skylights with controls to save energy, and envelope system enhancements
> Operable windows with mechanical system inter-lock to control and minimize the use of mechanical heating and cooling
> Individual task lighting and thermal controls—such as low-velocity overhead fans—to increase occupant comfort and reduce electricity use
> Tubular skylights and light-diffusing interior fabric shades to spread light evenly
> 64-kW direct-current capacity photovoltaic (PV) system mounted on roof, designed to generate enough ower to offset the building’s annual energy use
> Monitors and clerestories constructed on the roof’s south side provide more daylight and enhance the stack-effect
> Over-sized roll-up doors connect users to the exterior environment
> Building dashboard displays monitor energy efficiency and report carbon-impact
> Building-management system interlock and monitoring for efficient mixed-mode operation
Skylights and operable windows offer 51% greater energy performance than a typical Calif. Title 24 code compliant space. The new HQ kept 95% of the existing building’s structural walls, slab, and roof deck intact, plus most of the curtain wall. Diverting, reusing, and recycling materials reduced waste into the landfill stream by more than 75%. DPR’s HQ achieved net-zero energy use within its first six months of operations. During this time, it used approximately 110,000 kWh of electricity, while the PV system generated 230,000 kWh, which provided a sizable margin to achieve annual net-zero energy. DPR is pursuing LEEDR for New Construction-v2.2 Platinum certification for its new HQ.
> DPR Construction, California, United States
> Duration: February 2009 - May 2010