Sustainable manufacturing and green initiatives aside, energy efficiency is a tough sell. Plentiful oil and gas supplies coupled with moderate pricing don’t make it any easier. Nonetheless, utility companies and regulators continue to prod industrial users along the efficiency path, offering carrots to complement sticks to travel that route.
More than 350 rebate programs from utility companies, government agencies and other entities are available to U.S. manufacturers who upgrade to premium efficiency motors, ballparks John Malinowski, senior industry affairs manager at Baldor Electric Co., Fort Smith, Ark.
Rebates can shave a few months off ROI calculations, but efficiency ratings on today’s electric motors make the difference between premium and standard motors negligible. A small uptick in motor efficiency is less meaningful than reliability and productivity gains, and those are the kinds of benefits OEMs are trumpeting, not energy efficiency.
Energy consumption barely registers as a consideration when fans are installed to improve worker comfort; after all, a ceiling fan is a poor man’s air conditioner, and it sips electricity compared to a compressor. Comfortable workers likely are more productive workers, although quantifying gains attributable to better air circulation is as difficult as calculating throughput improvements from better lighting.
Industrial fan manufacturers don’t even tout their units’ energy features. Instead, they focus on reductions in heating costs, particularly in the kind of high-ceilinged spaces common in food and beverage production and warehousing.
Food manufacturers “do a better job of insulating and sealing the cube off” than other industries, says Ed Quinn, a vice president at Big Ass Fan (BAF) Co., Lexington, Ky. But a tight building doesn’t trump basic physics, and the thermal stratification that occurs in a high-ceilinged building means that the air at the top is quite a bit warmer than the air at the bottom. Forcing the ceiling air back to where the humans congregate can cut winter-time heating costs up to 30 percent.
“We pay a lot of money to heat the ceiling to 80° F even if it’s 60° at the ground,” says Quinn. As an example, he cites the installation of two 24-ft. diameter fans at the Beer Store, a Mississauga, Ontario, liquor distributor. The fans shaved 18°F from the top-to-bottom temperature variation at the 125,000-sq.-ft. facility, which has a 34 ft. building height. That resulted in a 19 percent reduction in natural gas consumption during Canada’s nine-month winter, saving the firm $35,000.
Adequate air circulation often is a quality issue in food production, whether it involves a cheese aging room or an ice cream freezer, and that’s reason enough to homogenize temperatures that otherwise would stratify. Energy reductions from an operations perspective are almost incidental.
Energy economics are a more overt driver in lighting projects, though better illumination also translates to more productive workers and less product waste. Last year, BAF hitched its star to the LED bandwagon, leveraging the talents of its 65 in-house engineers and a direct sales network to work directly with industrial clients.
A high-bay LED fixture was the first product, with washdown-ready units and other options following, including T5 and T8 fluorescents for the tradition-minded. “We thought we were late to the LED curve,” says Quinn, “but there are still a lot of people who want to lamp with fluorescents.”
Light up my life
BAF fabricates the fixtures. The LEDs are from Cree Inc., a global manufacturer that exemplifies the new wave of lighting suppliers. Legacy brands like Sylvania and Westinghouse are being passed around like wards of the state while manufacturers of televisions — the primary users of LED — invest in technical improvements. Siemens recently bailed from the lighting business and Philips is following suit. Samsung and other TV makers are replacing them as exhibitors at lighting industry trade shows.
Electronics are a big part of LED’s advantage. The electric surge and slow start-up that are destructive to fluorescents and metal halide bulbs are non-issues with LED, which are rated at 150,000 hours of service. Maintenance savings from bulb replacement alone were calculated at $129,000 for a 400,000-sq.-ft. Walmart refrigerated distribution center built in Balzac, Alberta, in 2010.
Motor manufacturers stopped banging the energy-efficiency drum years ago, relying instead on mandated improvements to drive that benefit. The payback from premium motors is real, but the timeline is longer than most manufacturers willingly will accept.
Motor efficiency ratings ratcheted up a few percentage points to the 90-95 percent range under 2010 regulations, but the regulations exempted many categories, such as gear motors and brake motors. The exemptions gradually will disappear. Beginning in June 2016, open motors down to ½ HP will have to meet standards previously considered premium efficiency.