Walk into your local supermarket in mid-August, and the electricity consumption surrounds you. The combination of overhead lighting, air conditioning, cooler refrigeration and all those freezer compartments make that round-the-corner temple to the food pyramid (or the new food plate) one of the biggest energy hogs in town. To help manage high operating costs and extremely tight profit margins, supermarket owners are turning to fuel cells.
Fuel cells seem like almost magical electricity--producing machines. Supply them with hydrogen—or a fuel such as natural gas that can be re-formed into hydrogen—and through electrochemical processes, they will produce electricity, along with heat and water. No noxious exhaust, no carbon dioxide, and not even any noise. And they produce that electricity more efficiently than our central-station-based grid. Factor in energy losses from the time a fuel enters a traditional generating station until electricity reaches the wall outlet next to you, and you’ll find efficiency as low as 35 percent. On-site fuel cells are closer to 40 percent efficient.
The real value in a fuel cell, though, comes in applications that can take advantage of heat that otherwise would be wasted in the electricity-production process. In facilities where heating, cooling or both are critical to operations, capturing and using that heat can drive fuel-cell efficiency as high as 90 percent, meaning the energy potential of the fuels that otherwise might be wasted is being put to work. This recycling of energy makes fuel cells a great match for larger grocery stores.
“They’re perfect for supermarkets,” said James Warner, policy director for the Fuel Cell & Hydrogen Energy Association. “Cooling consumes a huge amount of energy, and when you’re in the middle of summer, it’s a tremendous vulnerability.”
When paired with absorption chillers, fuel-cell waste heat can be used to supply both building-wide air conditioning and refrigeration and freezing systems. It also can supply boilers used for wintertime heating and to keep coolers and freezers from frosting up.
The supermarket sector is growing rapidly, according to Willis McCullough, a sales manager with United Technologies Corp. (UTC). Since 2006, UTC has installed 12 stationary fuel cells in supermarkets and currently has contracts for an additional 14 units. He said operating costs can make or break a store’s profitability.
“The reality is the only moving target owners can affect is their operating cost,” he said, noting that, at a certain size, most retailers are paying similar wholesale prices for the food on their shelves. Profit margins are extremely tight for food retailers, so even small savings in how they run their stores can have a big bottom-line impact.
“Most of their operating cost is electricity,” McCullough said. “It’s a very competitive business.”
Reliability is another benefit of fuel cells. Not only can a power outage cost a supermarket up to $1 million in spoiled food, according to Warner, such an event also often forces a market to close its doors, so any available backup power can be dedicated entirely to refrigeration. A 400-kilowatt fuel cell can supply most of a store’s electricity needs indefinitely if it is connected to a constant source of natural gas, so customers can keep shopping even when the power’s out. And, with no emissions and virtually silent operations, the devices also face only limited scrutiny from permitting officials.
Of course, there is a rub, and as you’ve probably guessed, it’s cost. Without incentives, fuel cells only make economic sense in the few regions where rates have reached the $0.18 to $0.20 per kilowatt-hour (kWh) rate (Hawaiian supermarket owners take note).
“The incentives make or break every single job,” when the rates fall into the $0.10 to $0.13 per kWh rates most of us pay, McCullough said.
As fuel cell demand grows, equipment costs are falling, but those high costs aren’t only related to the machinery. Installation costs, including what electrical contractors and heating, ventilating and air conditioning pros charge for their work, also plays a big part in what store owners must pay.
“A lot of that is fear,” McCullough said, noting that those unfamiliar with the equipment can be intimidated by fuel cells’ reputation as a space-age energy source. “You’re installing a backup generator, a boiler and a chiller. There’s a fear factor that’s coming in that’s doubling our cost.”
McCullough noted that UTC is rewriting its contractor manuals to emphasize installation simplicity and that contractors’ bids often drop after they’ve done a job or two. He said such reductions will be critical if fuel cells can survive without the coupon-like appeal of state and federal incentives.
“It really is how we work with the engineers, designers and installers in how we get our costs down,” he said.
ROSS is a freelance writer located in Brewster, Mass. He can be reached at firstname.lastname@example.org.