Over time, Plastech’s natural gas bill has increased to $6,000 annually (Canadian) just to heat its shipping area. So the company began looking into alternative energy sources to lower its heating costs.
Plastech was most impressed with solar technology, but was hesitant after learning that dark colors are recommended for the wall to which a solar collection system is attached. The company’s 26,000-square-foot building features ivory-colored corrugated steel walls, and management didn’t want to paint them a darker, more absorptive color.
Then the company learned about Lubi solar air heaters, which feature perforated glazing. Developed by Enerconcept Technologies Inc. in Magog, Quebec, this technology makes it possible to install solar heaters on light-colored walls.
Plastech installed a Lubi solar air heater system on one building wall in late 2010. Besides $6,000 in annual savings, the system reduces Plastech’s CO2 emissions by 15 tons per year. In addition, Plastech received incentives from Natural Resources Canada and a rebate from the Energy Efficiency Fund of their natural gas utility company Gaz Metro. These incentives shortened payback on the project to four years.
Measuring 90 feet wide by 24 feet high, the system, from a distance, appears to be several rows of windows. In actuality, the system consists of 638 panels, each of which measures 3 feet wide, 1 foot high and 6 inches deep. Each panel also has 906 perforations that allow air flow to keep the panel cool, minimize heat loss to the environment, and increase efficiency.
Sunlight radiates through the panels’ glazing and is absorbed by the steel wall. This heat is then trapped as hot air within the plenum between the panels and the wall. When the 5,500-square-foot shipping area requires heat, a motorized damper opens and a 7,000-cfm indoor ventilation fan draws collected warm air into the area via DuraTex fabric ductwork.
The ductwork is 36 inches in diameter and hung with a cable suspension system approximately 2 feet below the 24-foot-high ceiling. Manufactured by DuctSox, DuraTex is lightweight and features linear diffusion orifices that evenly disperse the warm air.
If the shipping area doesn’t reach its set point temperature of 69 F from the Lubi system, a second motorized damper opens to add ambient heat recovered from production floor machinery through the same duct system. If more heat is needed, a Reznor propane gas-fired heater acts as a backup source, says Yann Rouleau, plant manager.
During the system’s 15-year life cycle, Plastech estimates it will save at least $90,000 (based on 2011 energy prices) in projected energy costs, eliminate more than 300 tons of CO2 emissions from the environment, and provide employees better indoor air comfort.
For more information on solar air heaters, call 866-829-1690 or visit www.enerconcept.com.