How to Choose a Gas Furnace for Use with Biogas
Choosing a gas furnace doesn’t have to be confusing or difficult. Natural gas is a popular choice for home heating because it burns cleanly and in many parts of the country it is affordable and easily available. It does need to be piped into a home and fed into whichever gas furnace is installed but once a gas line is run to a house, gas is an efficient and cost effective way to heat a home. Home that are adjacent to landfills or farmland (especially dairy farms and pig farms) may also be able to make use of biogas produced from animal and plant waste.
Every gas furnace comes with an efficiency rating that tells the consumer how good it is at burning the gas fed into it. The most common efficiency ratings are 80%, 90-92% and 97% or above. A gas furnace with an 80% efficiency rating will be the least costly to purchase but will cost the most to operate because it burns more gas to generate heat than a more efficient model. However, if a homeowner will only be in a home a year or two an 80% efficiency gas furnace is probably the best choice. The additional cost of a more efficient model will take longer than two years (in most cases) to recoup through fuel savings.
The most efficient gas furnace (97% or above) is typically not a good deal unless the homeowner lives in a part of the country where the cost of natural gas is very high or unless the homeowner knows the furnace will be used for a decade or more. Homeowners who know they will not be moving can comfortably choose the most efficient model available. Choosing a reputable contractor will insure the correct size of furnace and the most efficient ductwork is installed for maximum home heating comfort.
To use biogas in a gas furnace, it is necessary to insure the biogas generated is of the same purity as natural gas. For homeowners who live on a dairy farm and already have a biogas reactor installed, this means making a simple call the contractor who installed it to make sure the proper equipment is included to refine the biogas for home use. Once it is sufficiently refined, it can be used just like natural gas in any ordinary gas furnace.
In many parts of the country biogas is already used to heat homes, often without homeowners even realizing this. Some communities have been able to tap local landfills and refine biogas for home heating and in rural areas farms sometimes sell it to public utilities for public use. To find out whether biogas is already available in your area, or to find out how to install a biogas reactor on your own farm, contact your public utility or go to the EPA website to download free info on funding.