Verified Pellet Stove Efficiency Key to Industry Success

By John Ackerly | April 04, 2013

The pellet industry has been developing certification standards to ensure that consumers know the quality of the pellets they are buying, but a similar issue is being overlooked when it comes to the equipment that uses the pellets—the efficiency of the stoves. 

There is virtually no credible information available to consumers that indicates which stoves are extremely efficient, and which are pellet guzzlers. The federal and state governments should be clamoring for this information, because pellet stoves and boilers are the biomass heating appliance that most deserves incentives, and incentives are almost always tied to efficiency.

An efficient pellet stove should be receiving at least the same tax credits and rebates that solar panels receive, especially in the Northeast, Great Lakes states and Northwest.  Federal and state governments have made a huge mistake by not incentivizing pellet stoves, because they are typically far cleaner than wood stoves in the real world, they help save consumers money and they are a great way to reduce fossil fuel. The only catch is that some stoves are very inefficient.

The U.S. EPA does not require stove efficiencies to be reported, but it does endorse the Canadian B-415 standard, using higher heating values (HHV). The problem got worse when Congress provided a tax credit for stoves that were 75 percent efficient using the lower heating value (LHV), but neither Congress nor the IRS stipulated how efficiency was to be measured. The result is that manufacturers measure efficiency in various ways to arrive at 75 percent LHV, leaving the consumer unable to compare more efficient and less efficient stoves.

Virtually all manufacturers claim to meet the 75 percent LHV efficiency threshold that makes stoves eligible for the $300 tax credit, but it could be that only half the appliances on the market today are actually above 75 percent efficiency. LHV calculates efficiency as if the wood has no moisture, and is typically 6 to 8 percent higher than HHV.

Pellet stove efficiencies vary widely, with some performing extremely well and others lagging far behind. There are stoves on the market that are only 40 to 50 percent efficient, and others that are up to 90 percent efficient, using LHV. Without standardized information available, consumers don’t know which one they are buying.

For the residential pellet industry to succeed, it needs to provide reliable and accurate information about fuel and heating appliances. That way, consumers will save the money they expected to when they bought their appliances.

The Pellet Fuels Institute has done a great job initiating the process to set standards for pellets, so the industry can stay ahead of government regulation and address the needs of consumers. For appliance efficiencies, the industry is staying well-behind government regulation, which is coming, but also behind the expectations and needs of consumers.

Almost everyone who buys a pellet stove today does so to save money. What they don’t realize is pellet stove efficiencies used by the fuel calculators are an estimate based on an EPA default number, at best. At worst, they are far off the mark. The EPA default efficiency is 78 percent HHV, a full 10 percent higher than the 68 percent HHV many experts think the actual industry average is.  Lots of calculators use 80 percent, and the U.S. Forest Service chose an even higher number, 83 percent. 
For now, the safest thing for consumers who want higher efficiencies is to buy pellet stoves that are EPA certified.  A wide range of value and high-end stoves are EPA certified, from manufacturers such as Harman, United States Stove Company, Englander and Lennox. 

Our government has failed to do much at all to help incentivize residential pellet heating equipment, even though it has tested extremely clean in both the lab and the field. While European countries include pellet appliances along with solar and geothermal in their efforts to promote renewable energy, the federal government and most states have neglected a technology with huge benefits for the environment, consumers, energy independence and jobs.

The industry needs to show that it’s willing to step up and provide the data and the quality control that other renewable energy sectors provide. That includes not only standards to provide transparency for fuel quality, but also for transparency of verified appliances efficiencies.

Author: John Ackerly
President, Alliance for Green Heat