When PNC Financial decided to push farther than the LEED (Leadership in Energy and Environmental Design) Platinum certification for their model net-zero energy branch in Fort Lauderdale, the goal was high: 50% energy savings and the same or better comfort for staff and customers as compared to PNC’s 2500+ branches.
Thanks to solar panels on the roof and walkways, the building actually generates more electricity than it uses, sending the surplus to the grid. Sending excess power back to the grid is possible thanks to careful design and planning the company carried out with its architect, Gensler and green building consultants CJL Engineering and Paladino & Company.
PNC Financial specified a direct current (dc) power system from Nextek Power Systems to significantly increase the efficiency of their lighting system and its use of renewable energy generated at the building site. Nextek’s innovative Direct Coupling
platform eliminates wasteful power conversions inherent in conventional systems. "This is another example of PNC's commitment to innovation and energy efficiency," said Gary Saulson , PNC's director of Corporate Real Estate. "We expect the net-zero energy branch to spur business growth and development in the area. Ultimately, we hope it will inspire other businesses to adopt similar green building practices."
Most of the lighting in this PNC Bank branch is connected to the Nextek patented dc microgrid that uses the solar power
it gets converted into grid-compatible ac power. This allows the power generated at the site to be used avoiding two conversions: one from dc (solar) to ac (the grid), as well as from ac (the grid) back to dc (the electronic light fixture) amounting to a large integrated efficiency improvement. When the sun’s not shining, the dc microgrid powers itself by converting the grid power into dc at higher efficiency than any single device can accomplish affordably on its own. For more, see the video
AC or DC Power?
Nextek CEO Paul Savage says PNC Financial’s use of dc microgrid technology represents a growing trend in net-zero energy building design. “In today’s competitive marketplace it is not enough to install solar panels on the roof and put a plaque on the door announcing you’re sustainable. Thoughtful design that reduces the building’s power requirement first is what’s needed, and that’s what PNC is doing.” By connecting the clean dc power generated by the sun to dc consuming lighting inside the building, and adding daylight harvesting and other control strategies, the branch’s lighting will consume 70% less power from the grid.