Whether you are burning natural gas to run a furnace or boiler or using electricity from coal-fired electric utilities to run your air conditioner, for many homeowners, heating and cooling our homes is our single largest contribution to global warming, making up about 30% of the greenhouse gas (GHG) emissions for an average Minnesota household.

There are a variety of options available for heating and cooling our homes that will reduce GHG and fortunately, making an effort to reduce your home’s global warming role can also pay off in reducing your energy bills. Keep in mind that some options will require a pretty significant up-front investment, so you’ll need to weigh the initial costs against the long-term savings you’ll reap- for you and the environment.

You’ll also want to make sure to maximize your investment by making an effort to improve your home’s overall energy efficiency through adding insulation, weatherizing and possibly also upgrading windows and doors. Local organizations such as the Neighborhood Energy Connection and the Center for Energy and Environment can help you figure out what steps you can take that will make the most sense for your home and budget.

Here’s a quick overview of some options you might consider:

Biomass stoves

These stoves are designed to burn corn, pellet fuels or wood at fairly high efficiency levels. In addition, biomass resources are considered GHG neutral, because the carbon dioxide (CO₂) generated in producing energy is compensated by the CO2 used by the growing biomass crop, whereas using fossil fuels such as natural gas or fuel oil “unlock” stored carbon.

Geothermal (ground source) heat pump

These systems have the benefit of working to provide both heating in the winter and cooling in the summer. They are designed to take advantage of the fact that much of the upper 10 feet of the Earth’s surface maintains a nearly constant temperature between 50° F and 60° F and there’s no “fuel” required, however, they do need electricity to run the heat pump. Geothermal systems are generally more expensive to install, but typically have a payback of five to ten years, depending on the type of system chosen and your current heating costs.

Upgrade your furnace or boiler

Many homes still contain furnaces or boilers that are 30 or more years old. Modern furnaces and boilers are much more energy-efficient; often 20% or more, than these older systems and it’s worth exploring an upgrade, especially if your home uses radiators that might require replacing in order to take advantage of one of the other available options. A list of furnace and boiler manufacturers and a savings calculator can be found on the Energy Star web site (see Resource Box).

Learning about different heating and cooling options can take some effort, but the work is usually worth it. Because prices can vary considerably based on the size and age of your home and the type of system you’d like to install, don’t be afraid to talk to more than one installer to find the best fit for your home.

Events such as the Living Green Expo feature exhibitors and workshops where you can learn more about alternatives such as those described above and other options that may be available to you. The 2008 Living Green Expo will take place May 3-4 at the State Fairgrounds. Contact information for past exhibitors can be found at livinggreen.org if you missed the Expo or don’t want to wait for the next one.