FUELS: THE GOOD, THE BAD AND THE SMOKY
No fuel source, with the possible exception of the sun, comes without an environmental cost. But each affects nature’s balance sheet in a different way. Here are some of the most notable pros and cons of common fuel sources.
NATURAL GAS AND PROPANE
PROS: Cleanest-burning fuels—least air pollution. Abundant in North America.
CONS: Non-renewable. Production has big environmental impact. Emits methane, potent greenhouse gas.
HEATING OIL
PROS: More-efficient burners and low-sulfur fuel now available. Potential transition to biofuels and wood-based ethanol.
CONS: Non-renewable. Production and transportation linked to big environmental footprint. CO2 emissions contribute to climate change.
WOOD
PROS: Renewable, plentiful and locally available. Little contribution to climate change.
CONS: Particle emissions contribute to air pollution. Must be burned correctly in efficient units to be clean.
CORN
PROS: Renewable and abundant in farm country. Little contribution to climate change.
CONS: Can require petroleum-based fertilizers and pesticides. Potential conflicts with burning food crops.
Wood stoves are fixtures in many northern homes, but those made before 1988 can emit between 15 and 30 grams of fine particles every hour. Stoves made after 1990 are EPA certified at 4.1 grams per hour for catalytic-type designs and 7.5 g/h for the less-complicated and more common non-catalysts. When buying a new wood stove, look for the EPA hang tag, which specifies the unit’s emission level. The only way to achieve that level is to burn dry, seasoned wood in a hot fire.
The hottest trend now is wood burning is pellet fuel, common in Europe. Pellet stoves are easier to feed and operate than log burners, and they can burn very efficiently. But compared to a typical natural gas furnace or low-sulfur oil boiler, pellet stove release considerably more particulate matter, according to the Brookhaven study.
The cleanest way to burn wood, whether in the form of pellets or logs, is in a state of the art boiler. Manufacturers have learned how to pull most of the heat and pollution out of the wood through two-stage gasification and high-temperature combustion that produces no visible smoke. Particle emissions as low as 1 g/h are possible.
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