Landfills are a necessary component of contemporary life. According to the US EPA, the average person in the U.S. produces nearly 1,130 pounds (513 kilograms) of waste per year, and the vast majority of that ends up in landfills. Much of that trash decomposes, and releases methane and CO2, both of which are greenhouse gasses. However, methane is also a gas which can be used as a fuel, and increasingly, landfills are beginning to realize this is an energy resource and are making use of it.
At present, landfill gas is the source of power for more than a million homes and of heat for over three-quarters of a million homes in the US. In addition, it is also provides fuel for natural gas-powered vehicles as well as power and heat for industrial process uses. Nearly 600 sites throughout the country are using the mathane from landfills to produce electricity, heat, proces energy, and even pipeline-quality natural gas and compressed and liquified natural gas for vehicle fuel.
Methane is 20 times more potent than CO2 as a greenhouse gas for trapping heat, and landfills are a major source of methane emissions. However, according to the EPA, 60 to 90 percent of the methane produced by a landfill is captured by a typical landfill gas energy project.
Capturing and using the methane from landfills serves the dual purpose of keeping these greenhouse gasses from directly entering the atmosphere and providing an alternative to fossil fuels. These programs have been encouraged through tax credits and grants as well as by the renewable energy portfolio standards many states are adopting for their public utilities.
Even if the volume of waste per capita could be cut significantly, landfills and trash are still going to be present. As with other materials recycling programs, it only makes sense to tighten the loops and take better advantage of the available resources in ways like this.
via: Smart Energy Portal