Straight answers to tough questions about wood heat

November 23, 2010

NOTE: Images in this archived article have been removed.

Our friend and colleague, Vanessa Percival, the Ontario distributor of Jotul and a number of other brands, asked me a while ago to help her solve a problem. Some of her dealers said that their staff members are often faced with challenging questions from customers or from reporters about the environmental suitability of wood as a home heating fuel. So we thought up some really hard questions and answered them as briefly as possible. Vanessa’s staff then emailed the result one question and answer each week (formatted nicely on a single page) for ten weeks to the dealer network. The program was well received. Vanessa has generously allowed us to publish them on The Woodpile. We’ll present half of the Q&A this week and the other half next week. Here is an MS Word file of the whole set. Feel free to distribute the article provided you give suitable credit and don’t alter it without permission.
John Gulland


Image RemovedWhen a local journalist asks for an interview you never know what kind of question you might be asked. With negative news about wood smoke pollution in the media these days, there is a good chance you will be asked an awkward question. You don’t want to be stumped, first because it is embarrassing and second because you’ll miss an opportunity to set the record straight. You might even be asked difficult questions by customers who need assurance that wood heating doesn’t have to be ‘dirty’. Here is a list of awkward questions you might be asked:

  1. Shouldn’t we be using new sources of energy instead of going back to older, polluting sources?
  2. If everyone heated with wood, wouldn’t the air be polluted and wouldn’t the forests be destroyed?
  3. Shouldn’t we be planting trees to combat global warming instead of cutting them down and burning them?
  4. Isn’t the idea that advanced technology, EPA certified appliances limit pollution to acceptable levels just spin put out by industry lobbyists, supported by gullible bureaucrats?
  5. Isn’t it selfish for a householder to heat with wood to save a bit of money when they are polluting their neighbours’ air in doing so?
  6. When all the time and work and maintenance expenses are considered, isn’t it just as expensive to heat with wood as with oil, gas and electricity?
  7. Greenhouse gases are emitted when wood is burned, so when you cut down a tree and burn it, aren’t you contributing to global warming?
  8. Doesn’t wood heating cause a lot more house fires than oil, gas or electricity?
  9. Isn’t the fact that the Lung Association says wood stoves pollute indoor and outdoor air a convincing argument for restricting wood burning?
  10. With landfill sites filling up fast, and the costs of disposal rising, isn’t it practical to reduce household garbage by burning paper and cardboard in a wood stove?

Here are some straight answers you can give to help set the record straight.

1. Shouldn’t we be using new sources of energy instead of going back to older, polluting sources?

There are no “new” sources of energy that are likely to prove viable. One of the newest energy sources is nuclear power, which has its own environmental problems and is controversial. Regardless of the energy source we choose for home heating, its use will have environmental impacts. The burning of oil and gas contributes to global warming, and their production is declining in many countries, meaning that their price is likely to go up as demand increases. While oil and gas don’t appear to pollute at the point of use, their exploration, production, refining and transportation cause severe environmental damage. Only a relatively small percentage of electricity is from renewables like hydroelectric dams, and even then there are environmental problems due to flooding large areas. Wind turbines will never produce enough electricity to be used widely for home heating.

Firewood, on the other hand, can be produced with slight environmental impact because it needs little processing and most of it is used close to where the trees grew. Wood is the most economical and accessible of all renewable energy resources for many households and it has value beyond the displacement of fossil fuels and reduction of greenhouse gas emissions. It is practiced on a small scale and the householders that use it gain a better understanding of their impacts on the environment than users of other energy sources. Families who heat their homes with wood responsibly should be recognized for their contribution to a reduction in greenhouse gas emissions and a sustainable energy future.

In a modern context, and knowing what we now know about the environmental impacts of all energy use, wood can be thought of as a ‘new’ energy resource, provided it comes from sustainable sources and is burned in advanced combustion appliances.

2. If everyone heated with wood, wouldn’t the air be polluted and wouldn’t the forests be destroyed?

Probably, but it would be foolish to suggest that wood heating is suitable for everyone. For example, firewood is not a good fuel for people unable or unwilling to do the physical work involved. Wood is not the best fuel for people living in large, densely populated urban areas because the air there is already fouled by traffic exhaust, industrial emissions and large residential developments. But people living outside large urban areas in smaller cities, towns and rural areas can benefit from heating with wood. They tend to have larger lots for the storage of a winter’s firewood supply and they are closer to the woodlots that provide fuel.

Large parts of North America have highly productive forests that could sustainably supply fuel for far more homes than are currently heated with wood. The productivity of many forests can be improved by thinning, and this process could yield a large amount of wood fuel. Advanced technology wood heaters can effectively burn tree species that have historically been considered inferior. Poplar, spruce, pine and willow can be used as firewood in modern appliances. Firewood production can provide the incentive for good forest management and its use can reduce greenhouse gas emissions by displacing fossil fuels.

“. . . current practices of obtaining and using wood energy are the foundation on which an expanded residential wood heating sector should rest . . . such an expansion is compatible with maintaining forest biodiversity and reducing greenhouse gas emissions.” Ole Hendrickson, forest ecologist. See: Residential Wood Heating: the Forest, the Atmosphere and the Public Consciousness

3. Shouldn’t we be planting trees to combat global warming instead of cutting them down and burning them?

Yes, forests absorb carbon dioxide (CO2) as they grow, so by increasing forest cover, more CO2 is stored (sequestered) in trees and kept out of the atmosphere. But trees and forests go through stages as they grow and mature. Some trees are damaged by ice and wind storms, some are hit by lightning, others are weakened by insect infestations and all trees reach maturity and die, just like other plants and animals. This constant transformation of forests means that some wood can be taken for energy purposes while the forest remains healthy and continues to absorb CO2 from the atmosphere. When we displace the use of fossil fuels by heating with sustainably harvested wood, there is a net reduction in greenhouse gas emissions.

Sustainable forest management is defined as uneven-aged selective harvesting, thinning of dense stands and removal of poorer quality trees, while leaving seed trees of all present species and ages, and some standing dead trees to provide wildlife habitat.

4. Isn’t the idea that advanced technology, EPA certified appliances limit pollution to acceptable levels just spin put out by industry lobbyists, supported by gullible bureaucrats?

No, the emission reductions are real. Tests of individual advanced technology stoves show that they produce between 60 and 90 per cent less smoke than the old ‘airtights’. Most advanced stoves average between two and five grams of smoke per hour of use, whereas the old stoves emit as much as 40 grams per hour. In Libby, Montana, where 1130 old wood stoves were replaced by EPA certified models between 2005 and 2007, the average outdoor air pollution (from all sources) was reduced by 30 per cent and indoor air pollution by 70 per cent compared to previous years. All cities and towns with concerns about winter air pollution can achieve big improvements by promoting the use of only advanced technology wood heaters.

5. Isn’t it selfish for a householder to heat with wood to save a bit of money when they are polluting their neighbours’ air in doing so?

A person who burns wood badly and inflicts wood smoke on neighbours is indeed being selfish. Each person who heats with wood must take responsibility for their impacts. Unlike the hidden impacts of the other heating options, the primary environmental impact of wood heating is the emissions produced at the point of use. A household’s skill at wood heating and their regard for their neighbours can be seen at the top of their chimney, where there should be no visible smoke. That makes everyone who heats with wood instantly and visibly accountable for their actions.

Using advanced technology equipment, seasoned firewood and responsible operation, there is no reason for smoke to be visible at the top of a chimney, except for a few minutes when a fire is kindled.

Over the past thirty years a social consensus has emerged that drinking and driving is not acceptable behaviour. A similar consensus has formed around exposing other people to second-hand tobacco smoke. Maybe it is time we all agreed that exposing neighbours to dense wood smoke is not socially acceptable behavior. We should feel a twinge of guilt when we see smoke coming from our own chimney.


Tags: Biomass, Renewable Energy