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By Bruce Barker THE
HIGH COSTS of natural gas and electricity are forcing farmers to move back to
an old standby. Coal is making a comeback in western Canada and some farmers
are putting a serious dent in their heating bills. Previously, Falkenberg's two poultry barns, both two-storey 46-foot by 252-foot, 48,000 square foot barns, required two natural gas boilers to heat them, with 1.6 million BTU and 1.2 million BTU burners. Barn temperatures are set as high as 93 F when chicks are brought in and as low as 68 F when the chickens are ready for shipping. To heat the barns, hot water circulates through pipes that run along the walls. Falkenberg's $65,000 conversion to coal includes all associated hoppers, bins, augers and pumps, including an addition to his shop to enclose the coal boiler. His boiler, rated at 2.3 million BTUs, was manufactured by Nova Metal Tech of Sherwood Park AB and retails at $32,650. A Wheatland 40-tonne hopper bin stands outside the building and holds several weeks supply of coal. An auger automatically fills a two-tonne hopper inside the building. The hopper bin feeds the stoker auger that keeps the coal boiler burning at the required temperature. A blower fan also supplies air to the burner and helps regulate heat. The two-tonne hopper was an innovation that Falkenberg felt was important, for several reasons. He didn't like the idea of having 40 tonnes of coal indoors, where an accidental fire could burn the building down. And the two-tonne hopper inside allows wet coal to dry, so there's less chance of bridging. If the coal bridges in the outside hopper and interrupts supply, the coal inside the building will burn for close to 24 hours - long enough to get him through the night without losing heat. Half-hp electric motors circulate water heated in the coal burner to the barns, through two-inch yellow jacket pipes. Pipes to the barn are buried about two feet below ground and insulated to R-80. The water system is pressurized to 10 psi. Most farm-sized coal boilers run on low pressure, so structural engineers aren't required in the manufacturing process. A 45-gallon expansion tank compensates for changes in water volume due to heating and cooling. Operation costs cut by two-thirds On extremely cold days, Falkenberg expects to use about two tonnes of coal per day. Laid in, his cost of coal is $38 per tonne for oiled coal. At that rate, operating costs could run as high as $2,400 per month in the winter. The most he used was in the 1.25 to 1.5 tonne per day range, although January and February this year were unusually warm. While just an estimate, Falkenberg expects coal costs to be about $12,000 to $15,000 per year. Compared to natural gas at $8,000 per month, he predicts substantial savings in operating costs. Even if rebates reduce his natural gas costs to more historic levels, Falkenberg still figures he'll be ahead of the game. Greenhouse - 16 years of coal heating At St. Albert AB, Chris Wirblich has been heating with coal since April 1985. His conversion 16 years ago was driven by the same economics as today. The only difference was that natural gas didn't peak quite as high. "There was a pretty good run up in price back then, too," says Wirblich, who operates St. Albert Greenhouses with his wife, brother and parents. "We felt coal was the way to go and it has saved us a lot of money since then." Wirblich heats almost 16,000 square feet of greenhouse, consisting of four 26- by 96-foot bays, plus another 60- by 96-foot greenhouse. Since insulation is non-existent on the walls and ceilings, heat is a major cost of production. Yet Wirblich's coal costs over the four winter months - November to February - is only $2,000 per month. His yearly coal bill is $14,000. In the dead of winter, if temperatures fall below -20 C, he has to supplement his coal heat with a stand-by natural gas boiler. "In 1985, before we converted to coal, our natural gas bill was $26,000 at a price of $3.50 per GJ. Today, without a rebate, our natural gas bills would have been $50,000 for the year if we relied just on natural gas," says Wirblich. He runs a 1.6 million BTU All-Canadian Boiler. Other than the stoker auger being replaced in 2000, he's had few problems with the 16-year-old heating system. "When you're pushing 400 tonnes of coal a year through, something has to wear out," says Wirblich. "But the repairs have been pretty minimal." When the heating system was converted to coal, the original system used steam heat circulated through fin-type registers in the wall. Wirblich changed to a non-pressurized water heat that circulates in a manner similar to Falkenberg's. He also has a few forced-air fans that use a heat exchange system similar to a radiator for heat transfer. Water circulates at 20 psi, at a temperature of 180 F. Two-hp electric Armstrong pumps circulate the water through three-inch water lines. Wirblich spent about $35,000 to convert to coal heat in 1985. He built a separate building to house the boiler. A 20-tonne hopper bin sits inside the boiler room and coal automatically augers into the stoker. Little effort required Coal heat isn't like natural gas. It takes some effort. But neither Falkenberg nor Wirblich says it takes much time. Falkenberg's ash system requires little attention. His boiler sits four feet above the ground and he built a removable ash box below it. Once a week, he uses a tractor with a front-end loader to remove and empty the box. Wirblich approached his system differently. An auger leads from the ash pan of the boiler outside to a box that stores the ash. At the start, ash was augered onto the ground outside, but embers burnt down the original boiler room. Now, ash is augered into a metal ash box. "It takes five minutes a day to auger out the ash from the boiler and the box needs to be emptied once per week," says Wirblich. He requires a load of coal every week to 10 days, depending on the weather. The coal is dumped on the ground. He fills his hopper bin with a 40-foot, seven-inch grain auger. A front end loader is used to move the coal from the stockpile to the auger. Coal-fired home heating Coal heating isn't just for barns or greenhouses. Dan House, an acreage owner at Zehner SK, recently converted to coal heat. Previously on electric baseboard heat, he was paying $7,200 per year for electricity. Now on coal, his electrical bill is around $1,500 and his coal bill is about $1,000 per year. That saving - $4,700 per year - means a payback of about three years on his $15,000 cost of conversion. "Our capital has been paid for. Now we start getting money back," says House. The conversion to coal was a little more costly than if House had previously heated with a forced air or water system. He initially installed electric heat because bringing natural gas to the yard would have cost $14,000, before the cost of the furnace and installation. Putting ductwork into his house cost $3,500. The rest of his $15,000 expense for coal conversion included a Homesteader quarter-million BTU coal boiler, stoker, hopper and water piping to the house, barn and greenhouse. "We went with a larger boiler because we wanted to have room for expansion to the barn and greenhouse," says House. At the house, a heat exchange system converts water heat to air heat for circulation through the ductwork. He hasn't put heat into the barn or greenhouse yet. House hasn't completely automated his system. He dumps a truckload of coal into a small storage shed beside the boiler. His stoker has a small hopper that holds about eight five-gallon pails of coal, which he fills by hand, twice a day. "I can handle a lot of coal for the price of a storage bin and auger," says House. "It only takes 10 minutes, twice a day, but it does tie you down to the farm a bit." House cleans out the ash pan once a week and uses the ash as fill for holes in his driveway. Where do you find coal? Coal mines are scattered throughout Alberta and Saskatchewan, but most are owned by major coal companies whose businesses are power generation or coal export. Wirblich, a St. Albert greenhouse operator, has purchased coal from TransAlta at Wabamun near Edmonton. However, he found service to be lacking for small customers like himself. He now buys coal from Dodds Coal Mine at Ryley, a privately operated mine in east-central Alberta. Besides better service, Wirblich says he has about "half the ash compared to TransAlta's coal." Every load of coal varies in BTU content and water content. Alberta's coal supply is typically high in BTU content and low in sulfur. Low sulfur content is important as it reduces the amount of sulfur dioxide generated during combustion. Sulfur dioxide has been identified as a greenhouse gas that may contribute to global warming. Lower water content is also important. During burning, the water evaporates, which uses BTUs and results in lost efficiency. However, every load of coal varies so, at best, suppliers give only estimates of BTUs and water content. Dodds coal averages 9,000 BTUs per pound with a water content of 20 percent. It's a family operation with four owners. Co-owner Dayna Kudrowich says the mine has become much busier in the past year. Seventy percent of its shipments go to farmers and 30 percent to greenhouses. Dodds sold 30,000 tons of coal in 2000 and expects to push 40,000 tons in 2001. Oiled stoker coal has been selling for $30 per ton while unoiled stoker coal sells for $27. Oiled coal reduces dust. "We have people buying from Manitoba because our coal is still cheaper when you compare it to the softer, lignite coal at Estevan," says Kudrowich. Dodds maintains a list of trucking companies that haul coal across the Prairies. Often they schedule a load as a back-haul to reduce freight costs. Some local heating companies may also carry coal, along with firewood and wood pellets. All Canadian Hydronic Heater and Stoker Nova Metal Tech Ltd. manufactures the All Canadian in five models ranging from 500,000 to 2.3 million BTUs. The All Canadian has a 21-year history. Nova Metal Tech has been building them for 11 years. Coal is the most readily available, cheapest and best suited fuel for the units, but alternative fuels, such as pelletized sawdust, pelletized straw and cubed wood shavings can also be burned in the boilers. All Canadian boilers have a secondary burning chamber that ignites escaping gases and increases burning efficiency by 40 percent. Vertical tubes in the heat chamber, in combination with spiral heat diffusers, improve heat transfer to water. The spiral heat diffusers also work as cleaning devices in the tubes to scrape away fly ash sediment. Direct drive gear boxes reduce the potential for breakdown and further automate the units. A control panel monitors water temperature and regulates coal feed. Full automation is achieved with the All Canadian system.
Trevelles Contracting Ltd. RR#2, Site 3, Box 9, Kingman, AB T0B 2M0 |