With 369,000 square feet under roof, it would seem McCormick & Co.'s sprawling distribution center in Belcamp would have an eye-popping power bill, with some 3,300 light fixtures and a refrigerated storage area big enough to drive forklifts in and out.
But in the past year, the 81/3-acre Harford County warehouse has generated more power than it has consumed, making it the first "net-zero-energy" building in Maryland and one of a small but growing number nationwide.
The Sparks-based spice and flavoring manufacturer first overhauled the building's lighting and air-handling systems. Then McCormick installed 7,500 solar panels on the vast rooftop, which generate enough power to offset the electricity the warehouse uses at night and on cloudy days.
"On bright, sunny days, our meter's spinning backward," said Jeff Blankman, McCormick's sustainable manufacturing manager. "And at night, we're buying power from the grid."
Net-zero buildings like McCormick's warehouse are part of a broader movement to get homeowners and owners of commercial structures to squeeze the waste out of their energy consumption for economic and environmental reasons.
Energy efficiency, experts say, saves money and reduces pollution. For businesses, it can help boost competitiveness.
More than $400 billion is spent per year powering homes and commercial buildings in the United States, according to the Department of Energy. Structures consume more than 70 percent of the electricity used and account for almost 40 percent of the nation's climate-altering carbon dioxide emissions. About half of the cost and emissions are attributable to commercial buildings.
"The buildings in this country that we work, shop and go to school in cost about $200 billion annually," said Maria Tikoff Vargas, who is leading the Energy Department's "better buildings challenge" aimed at improving energy efficiency. "There's a lot of waste that exists now in the system, so the real goal is to get rid of that energy waste."
In 2007, Congress called for a nationwide effort to achieve zero net energy use in all new commercial buildings by 2030, with the aim of getting similar results in all existing commercial structures by 2050. That's a tall order, with 81 billion square feet of commercial floor space nationwide, according to Energy Department estimates.
It's been slow going. The department lists just 10 net-zero-energy buildings in its online database. The New Buildings Institute, a nonprofit in Vancouver, Wash., tallied 21 net-zero buildings nationwide in a recent status report, with 39 other structures judged capable of getting to zero if they install solar panels or other generators of renewable energy. None was in Maryland.
But Vargas said the government's greater push is toward first squeezing the waste out of buildings' energy consumption before considering renewable energy.
McCormick got to net zero on its warehouse in a similar two-step effort. The company first set out to halve the 5 million kilowatt-hours the building consumed in 2006, Blankman said.
It cut lighting costs about 75 percent by replacing the distribution center's light fixtures with more efficient ones and by putting the vast majority on motion sensors. Aisles in the cavernous warehouse remain dark until someone approaches, and lights go off again after 15 minutes or so. In the cafeteria, motion sensors have been put on vending machines so they go dark between uses.
McCormick then struck a deal with Constellation Energy to install a 1.8-megawatt solar array on the distribution center's broad, flat roof.
The array on the Belcamp warehouse would likely have cost $8 million to $10 million to purchase outright, but the spice maker pays nothing up front, according to Mike Smith, Constellation's vice president of solar and efficiency sales. Constellation assumed the cost of installing and maintaining the array in return for McCormick signing a 20-year contract to buy the power generated by the sun hitting its warehouse roof.
The cost of solar-generated electricity in such a deal runs 10 percent to 20 percent below what a customer would pay for buying conventional power from the grid, Smith said.
Blankman said McCormick executives initially projected that the system would produce 80 percent of the building's power needs. After seeing how close that would bring them to net-zero consumption, they decided to squeeze more waste out of the operation. One upgrade involved putting motion sensors on warehouse conveyor belts so they would run only when pallets were placed on them.
"Back when electricity was cheap and controls less sophisticated, it wasn't unusual to let these run all the time," Blankman said.
The solar arrays have been operating since February 2011, and since then have produced 101 percent of the distribution center's electricity needs, generating a small excess of about 16,000 kilowatt-hours, Blankman said.
"What McCormick is doing is great," Vargas said. "It's leading the charge to pursue energy-efficiency measures."