Fireplaces: Wood, Gas or Electric?

Photo: Rubinovaite
With the long, chilly nights of winter here once again, many of us will turn to the comfort of a crackling fire for a little soul-reviving warmth. But in this day and age, it's hard not to feel guilty about sending greenhouse gases up the chimney for the sake of some fireside romance. Fortunately, not all fireplaces are an environmental no-no; some are actually the epitome of green. The gap between the good and the bad comes down to two main criteria: structure and fuel. Traditional is not the best There is really only one cardinal rule: no matter what fuel you're burning, stay away from the traditional but highly inefficient decorative fireplace with its open flame and chimney. Many actually draw heat from a house, acting like mid-winter air conditioner. By installing a high-efficiency, EPA-approved fireplace insert or a free-standing stove that encloses the open space, you can convert your un-green monster. Both wood and gas-fired inserts can reach respectable efficiencies of 70-85 percent (check their official rating before purchasing) that are miles ahead of decorative fireplaces. For those with a big budget and strong floors, a masonry stove such as a Tulikivi stove offers the basics of the woodstove with heat-retention qualities of stone or brick. Efficiencies approach 90 percent and they will radiate heat all day long with one quick fire in the morning. But, these stoves weigh thousands of kilograms and range from $10,000 and up. Contacting a local mason is the best way to go. The Masonry Heater Association has a certified member's directory. The second decision – whether to heat with wood, gas, or electricity – is a little harder to pin down. Electric It's true that electric heaters are almost 100 percent heat efficient but the larger issue is the energy source. Electricity from oil, gas or coal is only about 30 percent efficient due to the conversion process and the fact that these fossil fuels have high CO2 emissions. But, if your supply is from a renewable source like wind, solar, tidal or biomass with zero greenhouse gas emissions, then electric fireplaces are extremely efficient. Gas Modern natural gas stoves and inserts, on the other hand, attain lower on-site efficiencies and also suffer a much lower processing and transportation efficiency loss. The fact remains that natural gas is a fossil fuel and burning it contributes to climate change, no matter how efficient the appliance. Wood Finally, modern woodstoves and inserts are similar to natural gas for efficiency with the added bonus that wood is considered a carbon neutral fuel source (burning a tree releases only as much CO2 as that tree sequestered in its lifetime, leaving the net emissions at zero). Modern woodstoves like those from Vermont Castings have smoke emissions of just 2-5 grams/hour, down from 40-80g/h for older models. However burning wet wood or letting a fire smoulder can result in incomplete combustion, leading to higher smoke pollution levels and increased methane production. The former can lead to serious health problems and the latter's greenhouse gas potency is 20 times greater than that of CO2. The green woodstove A variation on the woodstove, for those who don't want the hassle of splitting and storing firewood or who don't want to have to think about their burning habits, is the pellet stove. These stoves use pellets made from compressed wood and biomass waste such as switchgrass pellets such as grape waste and olive pits. Corn burning stoves are similar but use corn kernels instead, a fuel that burns clean and does not require a conventional chimney. These stoves are easily converted to use other pellets as well. The green scale for fireplaces
  • #1 A well insulated home and a warm sweater!
  • #2 Electric fireplace with a green power source. Downside: green power hard to find, lacks romance, often tacky.
  • #3: Wood-fired masonry stove. Downside: may break the bank.
  • #4 Pellet stove/ high-efficiency woodstove. Downside: storing the pellets and wood, using them efficiently
  • #5 Wood-fuelled fireplace insert. Downside: using the wood efficiently
  • #6 Gas insert or stove. Downside: only considered green if you live where there are air quality issues and it's the lesser of two evils.
  • Mark Mallet is a LEED Accredited professional consultant and writer based in Vancouver. He specializes in the green building industry.