On paper, trucking in wood chips at an average $35 a ton to burn for heat seems like a much better deal than shelling out almost $2 million for No. 2 heating oil. But is the reality of biomass boilers as rosy as the idea? We caught up with Pleasant View Gardens to find out.
Since 2008, the 14-acre bedding and perennial grower has put in biomass burners at its two operations in Loudon and Pembroke, N.H. Its heavily forested locations made burning wood chips an obvious choice — not to mention the added appeal of having its heating dollars stay local rather than going overseas for oil.
Pembroke Nearing Payback But Over Capacity
The 7-acre Pembroke facility got the first unit, a Hurst biomass system that burns wood bole chips. The system, which Facilities Manager Russ Elkins likens to a Chevy in the biomass boiler world, uses reciprocating floor slats operating in sequence to move wood chips forward and dump them onto a conveyor. Known as a walking floor, the system provides the flexibility to burn a mixture of chip types if needed, though that hasn’t been necessary.
“It’s a good workhorse system,” Elkins says. “It has a tremendous number of moving parts, but we’ve done only routine maintenance.”
In other words, nothing unexpected; Elkins replaced a few pumps, meters, chains and bearings, the typical wear items.
Pleasant View Gardens is running through about 3,200 tons of bole chips a year, translating to about a $170,000 heating bill. That’s not a small number, but far from the $1 million bill the operation faced with oil at that location.
“We’re definitely saving $700,000 to $800,000 a year,” Elkins says. The savings helped Pleasant View beat its expected three-year payback time by a few months.
Even with the savings, the bole chip does cost about $10 more a ton than the whole tree chips that are burned at Loudon.
“We’re evaluating and don’t have the payback yet at Pembroke, but we’re almost there,” Elkins says.
In fact, the operation is already over-capacity for the Pembroke system, which runs a 100,000-gallon hot water storage tank. (Since installing the system, Pleasant View has expanded by almost 90,000 sq.ft.; if the folks there had it to do over, they’d install a larger 250,000- to 300,000-gallon tank.)
When temperatures dip below zero, supplemental heating with oil is a must at Pembroke. The predicted $30,000 cost to swap the system means Pleasant View is crunching numbers carefully before making a move, but its only an expansion away from making it happen.
Even with that, the operation is still upwards of 97 percent oil-free at Pembroke and 100 percent at Loudon.
Seeing Higher Efficiency And Savings
The Loudon system came later, due to its segregated greenhouse style and sloped lot. Time and costs were high for tying all the houses together into a single system, plus grading and other site prep to set the system. Here, the grower chose a Belgium-made Vyncke biomass boiler (think Cadillac) with multiple sensors, water jacketing in the boiler for higher efficiency, many convenience alarms and a 250,000-gallon hot water storage tank.
Adjusting to a European-made system hasn’t been without its challenges, like understanding metric conversions, waiting a minimum of three days to receive parts and accounting for the time difference when support is needed. But the benefits far outweigh those adjustments, Elkins says.
“There are quite a few Vyncke boilers in the States, so we can always borrow parts, and we’ve got three people on our staff, all trained by the manufacturer, on a rotation so we’ve always got support.”
At Loudon, Pleasant View is burning more wood (about 5,000 tons a year) and seeing higher efficiencies, translating into $800,000 a year in savings. The Vyncke system burns whole tree chips (tree tops ground up), which are lower cost per ton than the bole chips burned at Pembroke. That difference saves them $30,000 to $35,000 year in wood chips over Pembroke.
“The beauty of wood chips is, it’s renewable energy versus No. 2 heating oil,” Elkins says. “So before we were using oil, and all that money was going overseas. Now we’re spending roughly half a million dollars a year, and it’s all going into the local economy within a 35-mile radius of either facility.”
The biggest surprise with both systems has been the cost of boiler treatment, he says.
“It has to be tested about every quarter, and we spend more than $100,000 at each facility on boiler treatments.”
It was definitely an adjustment going to biomass, which takes time to ramp up and heat, from oil with its switch-on action, and the operation does see more in-season alarms from jammed wood chips and such. But Elkins says Pleasant View would do it again.
“When you’re saving the company a million dollars a year, that’s hard to argue with.”