Do Wood Stove Changeouts Work?
Residential wood heat in the U.S. is plagued by the same problems as Europe and scores of other cold countries: most stoves are old, obsolete and put out too much smoke. As a result, wood heating elicits a mix of appreciation, ambivalence and antipathy. Those who use it the most invariably love it. Those who use it the least, and often live in more urbanized areas, think it’s antiquated and polluting. One of the main solutions has been to incentivize the replacement of older, more polluting stoves.
The longevity of most stoves is a blessing and a curse. Unlike cars, refrigerators and HVAC equipment, and many other appliances, people keep and use their stoves far beyond their ideal retirement age. Eventually, turnover occurs. Every year, thousands or even tens of thousands of stoves are retired naturally. Some of the owners buy new ones, or switch to pellet stoves. And many old stoves retire when their owner passes. But natural turnover is not happening fast enough.
Stove changeout programs almost always rely on local, state or federal funding to subsidize the removal of old stoves and the installation of newer ones (or nonwood heating appliances). The goal is not only to reduce wood smoke pollution in a town or airshed, but also in the immediate neighborhood and inside the home. These programs are often compared to Cash for Clunkers, a $5 billion dollar federal program providing $4,500 vouchers for people who replaced their 18 miles-per-gallon or less cars with one that got at least 10 mpg more.
Some in Congress argued that a $4,500 voucher was too generous, and introduced a bill that only gave $2,500 for an exchange netting 7 mpg and $4,500 for one netting 13 mpg. The same debate surrounds each stove change out program: How much benefit should be required per dollar of the rebate? And how do you define the benefits and ensure they are real?
One unintended consequence of Cash for Clunkers, covered extensively in the media, was that most of the old cars turned in were American, and most of the new ones purchased were foreign. This phenomenon has not happened with stove change outs, but there are other unintended consequences.
In retrospect, Cash for Clunkers was generally considered far too expensive for the benefits it provided. With changeout programs, jurisdictions are steadily changing the rules to ensure that the air quality benefits match the funding. The Alliance for Green Heat is analyzing all existing changeout programs, interviewing program managers and exploring the cost-benefit calculations that may take root in coming years.
Increasingly, jurisdictions undertaking stove changeouts only want to replace older wood stoves with gas or electric appliances because they believe new wood stoves and even pellet stoves can still emit too much smoke. In areas facing the worst air pollution, public funding is going to help homes switch from renewable fuel to fossil fuel.
The core problem is that areas that need to undertake wood stove changeouts have some of the worst air pollution in the country. The agencies running the program have one mandate: lower particulate matter in the air. They see this as a public health imperative that benefits everyone.
The Bay Area of California recently launched a $3 million program, which is possibly the largest changeout ever. On the first day, more than 2,000 people applied and the program had to be closed to new applications due to lack of funds. Some in the industry warned that this program would not be popular because it did not allow wood stove replacements (only gas and electric). They were wrong. Like Cash for Clunkers, the program was so popular that it only met a small part of the demand. More homes could have been served with more air quality benefits if the rebates were smaller.
Changeouts can be very effective in small geographic areas, such as mountain valley towns that experience frequent inversions. But on a state or even large county level, wood smoke PM reductions can be hard to measure and verify, even after removing thousands of wood stoves, because only a tiny percentage of stoves replaced get replaced.
Ultimately, the $5 billion spent on Cash for Clunkers was just a drop in the bucket since there are hundreds of millions of cars on the road. The same goes with the $3 million that the Bay Area is spending, but it’s a start.
Moving forward, the questions remain: How to design a stove change out program that delivers the biggest bang for the buck? Can we show enough benefit to warrant increased funding? And potentially the biggest question of all: When will the federal government step in with matching funding?
Author: John Ackerly
President, Alliance for Green Heat