EPA Issues New Emissions Standards for Residential Wood & Pellet Stoves

On February 4, the U.S. Environmental Protection Agency (EPA) released updated emissions standards for new residential wood heaters, under Section 111 of the Clean Air Act. Prior to this 2015 final rule, the New Source Performance Standards (NSPS) were last updated in 1988. The revision of the standards reflect improved wood heater technology, which allows residential heaters to run cleaner and more efficiently, producing fewer emissions. For the first-time, new wood fired boilers, indoor wood-fired air furnaces, and single burn-rate woodstoves will also be regulated under the new rule. Residential pellet stoves are also included in the new emissions standards. In total, 2.9 million homes in the United States, roughly 2 percent, use wood heat. Among those homes who do use wood heat, the largest percentage of use is by those on the lower-end of the income spectrum. Pellet and wood stoves are growing in popularity as well; last year, the Energy Information Agency (EIA) reported that wood heat saw a 50 percent jump in 2013 in the New England region alone. 

According to EPA, emissions from new wood stove models will be reduced by two-thirds--producing $3.4 billion to $7.6 billion in public health benefits. Under the standard, newly manufactured heaters will cut fine particulate and volatile organic compounds (VOC) emissions by 70 percent with an expected reduction of 46,100 tons and reduce carbon monoxide (CO) emissions by 62 percent when compared to emissions without the rule. In communities that are heavily reliant on woodstoves for winter heating needs, exposure to pollutants such as CO and particulate matter can be disproportionately high.  Exposure to these pollutants is associated with numerous adverse health impacts, including cardio-vascular and developmental impacts, as well as asthma and various cancers.  The components of wood smoke are also precursors to ozone. In rural communities in particular, wood is often a secondary and, in many places, a primary source of home heating.    

The core of the rule is a 5-year phased plan, beginning this year, with final emission limits to be met by 2020. The first phase begins 60 days after the final rule is published in the Federal Register.  The first step-down will set emission limits for new wood and pellet stoves at 4.5 grams of particulate matter (PM) per hour of operation for both catalytic and non-catalytic stoves; most residential wood stoves on the market today are non-catalytic. Phase two of the plan takes effect in 2020, when the PM emission limit will be set between 2 and 2.5 grams per hour, depending on wood type used for emissions testing. According to John Ackerly, executive director of the Alliance for Green Heat, these standards will not adversely impact consumers, saying, “Over five years who knows what kind of innovation will happen, and that will enable stoves to hit 2 grams pretty easily without driving up the cost.”   

Pellet stoves, due to their higher burn efficiency, will be less affected in the near-term, but the pellets sold for use in these stoves must meet certain emissions criteria, as dictated by the EPA.  The pellet industry is concerned over the three different emissions testing methods that are allowable under the regulation.  According to Jennifer Hedrick, executive director of the Pellet Fuel Institute (PFI), “PFI has significant concerns that the current EPA language – allowing for U.S. pellet producers to choose among multiple standards programs – will cause more confusion than clarity among manufacturers, retailers and consumers as they try to grasp what the different programs and fuel standards mean.”  

Probably most noticeable to those shopping for a wood or pellet stove will be the absence of a consumer hangtag, with key stove emission and efficiency information. In the new rule, EPA retires the requirement for heaters to display the hangtag. However, EPA will allow the use of a special label on stoves which already meet 2020 emission standards, or are able to test under 2.5 grams per hour using cord wood.

While the new rule does not apply to existing heaters already in homes, it also does not replace any existing local requirements or regulations for wood heaters. Not regulated under the new rule are fireplaces, pizza ovens, fire pits, barbeques, chimineas, and masonry heaters. The EPA did propose to set emission limits for masonry heaters in this ruling, but postponed doing so until there is more efficiency and emissions data with reliable testing methods to draw upon. 

While various industry groups may have some problems with the implementation or timeline of the rule, it’s certainly a step in the right direction for the health of millions of households which rely on wood and pellet fuels as their main source of heat.

Author: Caitlin Madera 

For more information see:

Summary of Requirements for Woodstoves and Pellet Stoves, EPA

Overview of Final Updates to Air Emissions Requirements for New Residential Wood Heaters, EPA

EPA Finalizes NSPS for Residential Wood Heaters, Biomass Magazine

Increase in wood as main source of household heating most notable in the Northeast, EIA

Statement on EPA’s New Source Performance Standards Rule, Pellet Fuels Institute