SAGE » Q&AQ: Given home heating choices of electric heat generated by a natural gas-fired power plant, propane, or wood burning in a woodstove (no live trees cut, all downed wood), which option creates the least total environmental damage?
Asked by Barbara James, '58, Carmel, Calif.
Funny you ask, Barbara—this is a debate my housemates and I have often had. The short answer is "it depends," but if you're anything like my Stanford housemates, you won't be satisfied with that answer. The truth is, it does depend on many factors, from the exact type of heating appliances in your home to the local environmental conditions present in your community, so let's explore the short answer in more detail.
First, we need to clarify the term "environmental damage." Let's split it into two categories: global and local. First you've got climate change and the global implications of increased carbon dioxide (CO2)in the atmosphere. On the local side, you have the impacts of air pollution, such as smog and other pollutants, on human health.
If you were concerned only with the CO2, woodstoves are hands down the least "carbon-intensive" way to make heat for your home. Why? Because as trees grow, they suck CO2 from the atmosphere to create wood. When you burn this wood you are just returning that carbon back to the atmosphere, rather than tapping into new sources in the form of fossil fuels.
Since gas and electricity can't hold a candle to cordwood when it comes to global warming impacts, I decided to see how they stack up against each other. Power plants generate electricity the old-fashioned way—by heating water to drive a steam turbine. In the United States, that heat almost always comes from fossil fuels, and the process isn't terribly efficient. By the time the electricity makes its way to your home, often more than 50 percent of the fuel's energy has been lost in the production and transmission of electricity. That means the electric heaters in my house, supplied by natural gas-fired power plants, produce twice the global warming gases per unit of heat as directly burning fossil fuels in a home furnace. If your electricity comes from a coal-fired plant, as it does for most Americans, cranking that space heater will release up to four times the amount of CO2 into the global atmosphere as a conventional gas or oil furnace.
That's the climate view. But is wood always the best option? Not by a long shot. Even your most advanced woodstove will emit up to eight times more smog-forming particles per unit of heat than either a furnace in your home (natural gas or propane) or an electric heater at the power plant. For this reason, many municipalities have begun banning the use of woodstoves, especially during peak smog-forming months.
At my house, we've decided to take a balanced approach based on the conditions in our community. On the coldest nights we fire up the woodstove. Since we have an EPA-certified clean-burning stove and live in a fairly windy, rural location, we prefer emitting a small, dispersed amount of local air pollution—and reveling in the coziness of radiant wood-fired heat—to contributing to the global climate chaos.
Day to day, we keep our house pretty cool and use electric space heaters sparingly in occupied bedrooms, making sure to shut doors and closets to seal in the precious heat. This way, each person can decide how warm or cool to keep his or her own room, and we don't waste heat warming our hallways and common areas. And when the heating bill starts adding up? I remember my mother's advice and put on another sweater. If this frugal approach doesn't suit your taste, you can find your own balance by weighing the local environmental considerations against your personal tolerance for chilly toes.
