In the wake of an unresolved problem with wood pellet boilers in Haines, the Alaska Energy Authority has indefinitely extended a deadline for spending $1.2 million to put pellet-burners in Haines Borough facilities.
Engineer Jams Vail, energy infrastructure project manager for AEA, said on April 30 that the grant completion date “is not set in stone.” The money was to have been spent by June 30, 2016.
Instead, the agency looks at a project’s progress, and in light of setbacks here, a staged approach to installing pellet heaters here is a “better way to go,” Vail said. Only a few hundred dollars has been spent to date.
Vail recently came to town with Daniel Parrent, a biomass and forest stewardship coordinator with the U.S. Forest Service, in part to meet with owners of four wood-pellet heaters around town that appear to be suffering the same problem.
The “flame tube” or burn chamber in the four OkoFEN boilers in Haines – including one at the borough-owned Senior Center – have become corroded or burned out one or more times, Vail said. Other OkoFEN boilers are at the Chilkoot Indian Association, Eagle’s Nest Motel and Olerud’s.
All the boilers use the same, “premium”-grade pellet.
Representatives of Maine Energy Systems, who sell the boilers in the United States, have cited chlorine in pellets used in the Haines boilers as a possible cause of the problems. Recent tests by the company have shown the pellets contain a little more than 200 parts per million of chlorine.
MES said pellets burned in their boilers can accommodate a maximum chlorine content of 200 parts per million, but there’s nothing in company manuals that specifies that. Instead, the company suggests use of a “premium” pellet, but for all grades of pellets, the chlorine level limit is 300 parts per million, Vail said.
Messages left for a MES representative Wednesday were not returned by press time.
“There are truly experts we have access to. I can run what we’ve seen through those experts,” Vail said. “(The problem) can be a lot of different things” including metallurgy, system operation and environmental conditions, he said.
In the meantime, the borough is testing a higher-grade, stainless steel flame tube OkoFEN has manufactured called the “Alaska” model, but its success won’t be known until the end of another burn season.
AEA’s Vail and the Forest Service’s Parrent said the setback shouldn’t dissuade the municipality from pursuing the project it planned – placing pellet boilers in as many as 10 borough buildings.
“The issues we’re looking at should have no impact on the future of the project, unless there’s a reason to not use that particular boiler,” said Vail. Parrent said he expects the stainless steel burners will solve the corrosion problem, but even if they don’t, he doesn’t regard the issue as a major one.
“It’s a maintenance item, pretty much. (Flame tubes) only cost a couple hundred bucks. It’s like replacing brakes on a car,” Parrent said.
Vail said because pellet burners are a relatively new technology, there’s a “shakedown” process to getting them operational. “You almost always have a few bugs to work. Some systems are more operational than others. It will save money in the end. It already is.”
Former borough public facilities director Carlos Jimenez said the municipality has revised plans to put a pellet boiler first in Haines School. Instead, the the next boiler may go in at a new sewage treatement plant, possibly in a separate building to minimize corrosion typical at water plants.