Super Therm® coating saves fuel for food-hauling fleet
Heavy Duty Trucking • April 2010 • Photos Curt Lundberg
Sunshine brings warmth and happiness, but to refrigerated trailers it brings only heat, and too much of it. Those hot rays from far away can raise temperatures inside the trailer to unbearable levels and cause the reefer unit to work really hard to keep things cool.
That was the case with Pacific Shipping & Trucking of Denver, which has a two-way food products haul with temperature extremes that were difficult to deal with. Then came a special roof coating that proved to be an impressive solution.
The carrier moves truckloads of baked bread from Denver to Phoenix, then returns to Denver with ice cream, explains Keith Robertson, the fleet’s owner and president. Bread is maintained at (27°C) 80°F, but ice cream must stay frozen at (-28°C) -20°F – “extreme heat to extreme cold,” he says. It’s a drop-and-hook operation, with trailers full of bread left at docks in the usually hot southern Arizona city while empty reefer trailers wait nearby.
A driver backs his tractor onto an empty, then starts the reefer unit to begin cooling down the trailer’s interior so it can take on ice cream. Temps inside the trailer can be (48°C) 120°F or more, and it’s got to be cooled to below zero. “It was taking us two and a half hours to get sitting out in the sun to get to minus 10 – from there they can start loading – then,” Robertson says. “Now it takes 45 minutes to an hour,” so the reefer runs less and burns less fuel.
The product is called Super Therm®, a ceramic-based compound that blocks the sun’s rays and prevents the trailer’s roof from becoming a heat sink. The product costs $900 to $1,000 to apply per truck, but saves enough fuel to pay for itself in 10 to 11 months, Robertson says. He has had Super Therm® installed on 22 trailers involved on this haul and plans to put it on more of his 100 trailers.
Super Therm® is a water-borne insulating coating that also prevents moisture penetration and air infiltration over a surface, says its maker, Superior Products International, of Shawnee, Kansas. “It is the most effective and longest lasting ceramic insulation coating on the market today,” SPI claims on its website, www.spicoatings.com. It is ecologically safe, fire-resistant and approved for use around food by the federal Food and Drug Administration. SPI makes seven insulation coatings for various applications, and others for corrosion and fire control.
Super Therm® reflects over 95% of the three radiation sources from the sun, which are ultraviolet, visual light and infrared rays, the site says. On building roofs, where it has been used for more than 20 years, it does the work of 6 to 8 inches of traditional insulation. It is Energy Star qualified as a 20-year roof coating.
Curt Lundberg, a Denver-based distributor of SPI products who sold the Super Therm® to Robertson, did a study of Pacific’s bread-ice cream operation that measured fuel use before and after the coating was in place. As Robertson said, after coating roofs with Super Therm®, the cool-down time in Phoenix was cut by 1.75 hours or 44%. The study showed a reefer unit also used less fuel while under way: 20% less fuel on the outbound “hot” haul and 29% less on the return “cold” leg. A reefer burned thus 5.75 (21.7 litres) fewer gallons per day and saved about $13.50 with non-road fuel at $2.35 per gallon (3.78 litres). Long-term savings depend on the number of trips a trailer makes; at 200 to 250 trips a year, the savings could total $2,500, Lundberg says…($50,000 over 20 years).
If in Australia 21.7 litres x $1.80 per litre = $39.06 x 200 trips = $7,812 per annum x 20 years = $156,240 total fuel savings plus engine life extension and CO2 reduction!
Installation is fairly simple, he says. “You pressure-wash the roof with a detergent – we use Simple Green – then roll or spray it on. It goes on to the thickness of a credit card, 18 mils wet and dries thousandth of an inch. We have had it on buildings in Kansas for years and it doesn’t deteriorate and it lasts through hail storms. It will last more than 20 years, which is more than the life of a trailer. You don’t have to re-coat it at any time; you don’t even have to clean it for it to work.”
Lundberg has measured roof-surface temperatures and found them to be even higher than interior temps. “A roof gets to (62°C) 144°F in Denver in the sun. Elsewhere it’ll get to (93°C) 200°F,” he says. “By putting this on, the product doesn’t allow the roof to heat up. It’ll only be 2 or 3 degrees above ambient. It amounts to putting a tent over the trailer.” > Super Therm®.