©2013 Green Building Advisor. From The Taunton Press, Inc., publisher of Fine Homebuilding Magazine.
There are a lot of things not to like about fossil fuels. Most obviously, the burning of oil, natural gas, propane, and coal releases huge quantities of carbon dioxide into the atmosphere, where it traps heat through the greenhouse effect.
Fossil fuels were created over hundreds of millions of years when vegetation accumulated in oxygen-poor conditions and did not fully decompose before being trapped underground. Heat and pressure gradually turned that organic matter (and its stored carbon) into these various carbon-rich fuels. When we burn those fuels to heat our homes, generate electricity, or power our cars, the hydrocarbon reacts with oxygen, converting the stored carbon into carbon dioxide, which causes global warming.
But even if burning fossil fuels didn’t cause the release carbon dioxide and cause global warming (just for a moment, let’s say those climate change deniers were right), there would still be plenty of reasons not to burn these fuels.
The extraction of coal, oil, and natural gas is highly damaging to the environment. From mountaintop removal of coal in West Virginia to open-pit mining of tar sands in Alberta, Canada, to the newest fracking practices that are thought to be contaminating aquifers from Pennsylvania to North Dakota, the fossil fuel extraction business isn’t pretty.
There’s air pollution from burning these fuels. Natural gas isn’t so bad (except from a global-warming standpoint), but coal combustion generates significant particulate emissions and sulfur dioxide, causing acid rain, and both coal and oil combustion may release nitrous oxides and contribute to ground-level ozone and smog production. According to a 2010 report from the American Public Health Association, just the healthcare costs associated with air pollution from vehicles amounts to $50-80 billion per year in the U.S. (that’s as much as 60¢ per gallon of gasoline consumed); other estimates put that cost even higher.
When we buy fossil fuels we generally send money out of the community to support large corporations and foreign governments. That’s money that doesn’t stay in the local economy.
And then with oil there’s the issue of how much it costs to protect our access to this resource — fundamentally, that’s what took us into Iraq. We are spending billions of dollars per week in the Middle East, not to mention the thousands of American soldiers’ lives that have been lost and the lives of untold thousands of Middle Easterners.
If we accept that it would be a good thing to get off fossil fuels, how do we do that? It isn’t easy. Our modern American society has been built on a foundation of inexpensive fossil fuels. Our dependence is huge and deep-seated. Eliminating that dependence will be a mammoth undertaking — but, I believe, a necessary one.
While there are a lot of ways to approach this challenge, I’ll focus here on the micro-scale: what we as individuals can do to get off fossil fuels. This week I’ll look at our houses; next week, transportation.
Here are some strategies:
1. Insulate your house. By dramatically improving the energy performance of your house, you can reduce the heating loads enough that other, non-fossil-fuel heat sources can realistically satisfy those needs. Adding robust amounts of insulation when building a new house isn’t so hard — the extra cost can be at least partly offset by lower costs for heating and air conditioning systems — but with existing buildings it’s a huge challenge.
A so-called deep-energy retrofit may cost $100,000 or more for a typical home. It involves adding extra insulation to either the interior or exterior of the existing insulated shell of the house, upgrading to triple-glazed, R-5 windows, and significantly air-tightening the house.
If you don’t significantly boost the energy performance of your home, you can still wean yourself from fossil fuels — but it’s a lot harder.
2. Convert to a non-fossil-fuel heating system. Wood heat may be an option in some areas, but if everyone started heating with wood, air pollution would get a lot worse and we would quickly deplete forests. I generally consider this a realistic option only in very rural areas and areas not prone to weather inversions (atmospheric conditions trap air pollution in valleys).
Pellet stoves and larger pellet boilers are also an option — one that’s gaining a lot of ground in northern Europe and beginning to generate interest in the U.S. Wood pellets are made by compressing sawdust and other wood waste (sometimes whole trees) into small pellets that look like rabbit food. Pellet stoves and boilers are a lot cleaner-burning than wood stoves and older-style wood boilers, because the pellets are burned under careful conditions with supplied air that ensures very complete combustion.
If you get heating loads low enough, you can consider electric heat as a realistic option. But for electric heat to be an affordable option, a heat pumpHeating and cooling system in which specialized refrigerant fluid in a sealed system is alternately evaporated and condensed, changing its state from liquid to vapor by altering its pressure; this phase change allows heat to be transferred into or out of the house. See air-source heat pump and ground-source heat pump. should be used rather than standard electric-resistance baseboard heaters. With heat pumps, the electricity is used for moving heat from one place to another — such as from the outside air (with an air-source heat pumpHeat pump that relies on outside air as the heat source and heat sink; not as effective in cold climates as ground-source heat pumps.) or the ground (with a ground-source or geothermal heat pump) into your house. For every one unit of electricity consumed by a heat pump, two to three units of heat (sometimes even more) are delivered. We can think of the heat pump as being 200% to 300% efficient, though it’s not actually a measure of efficiency.
With heat pumps, I’m a big fan of the new generation of air-source heat pumps that are often referred to as minisplit heat pumps but are more correctly called VRF (variable-refrigerant-flow) heat pumps. These are made by such companies as Mitsubishi, Daikin, and Fujitsu. They perform almost as well as ground-source heat pumps and they cost a whole lot less, because digging trenches or drilling wells is not required.
3. Convert to renewable electricity. As astute readers will note, simply switching from gas or oil heating systems to heat pumps only helps wean us from fossil fuels if the electricity is produced from other than coal or natural gas power plants. Because the electric grid is so distributed, the electrons that flow through the grid come from many sources, and about half of the nation’s electricity currently comes from coal, with most of the rest produced by natural gas, nuclear power, or hydropower. The last two options are fossil-fuel-free, but in most places the electricity can be assumed to come from a mix of energy sources, with a significant portion of that from fossil fuels.
To be sure that one’s electricity is from non-fossil-fuel sources you can install your own renewable electricity system — with solar electricity or photovoltaics (PVPhotovoltaics. Generation of electricity directly from sunlight. A photovoltaic (PV) cell has no moving parts; electrons are energized by sunlight and result in current flow.) usually being the most practical option — or you can buy electricity that is designated as coming from a renewable energy source. I like the idea of installing your own PV system so that you can track your production and consumption and be sure that your consumption is being offset by solar electricity. Various tax credits, incentives, and dropping PV costs have made this option increasingly feasible in recent years.
Sourcing renewable electricity from the utility company is only an option if the utility company has a renewable energy program. Our company, BuldingGreen, pays about 4¢/kWh more for electricity through the Cow Power program  of Central Vermont Public Service Company; my wife and I do the same at home. That higher rate helps to pay for on-farm methane generators that have been built on at least a half-dozen large Vermont farms.
Next week, we’ll look at the more challenging issue of shifting to non-fossil-fuel transportation.
Alex is founder of BuildingGreen, Inc . and executive editor of Environmental Building News . He also coauthored BuildingGreen’s special report on windows that just came out. To keep up with Alex’s latest articles and musings, you can sign up for his Twitter feed .