Greenhouse gases are gases that trap heat in the atmosphere. Many greenhouse gases are caused naturally, but too much can cause harmful effects on the environment, such as the depletion of the protective ozone layer and climate change. Human activity has increased greenhouse gas emissions primarily in the form of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases, producing unhealthy levels. 

In 2007, energy-related activities accounted for 86.3 percent of total greenhouse gas emissions on a carbon dioxide equivalent basis. Ninety-seven percent of CO2 emissions, 35 percent of methane and 14 percent of nitrous oxide emissions came from energy production. The energy used to extract raw materials, as well as waste-to-energy incinerators, play a factor in this high percentage of CO2 emissions.

Another greenhouse gas, 72 times more potent than CO2 over the course of 20 years, is methane. Landfills are the largest human-made contributor of methane into the atmosphere.  When organic waste is disposed of in the trash, it ends up in a landfill with the rest of our non-organic trash. As the landfill is filled and covered, no air can pass through, causing anaerobic conditions. In these conditions, the decomposition of organic waste produces methane within the landfill that needs to be released to relieve pressure buildup. 

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There are several methods used to decrease landfill methane emissions. One way is through flaring the methane.The gas is channeled through a flare that burns the methane as it is released into the atmosphere, which still generates carbon dioxide, a less potent gas. Another method is capturing methane from the landfill and converting it into energy, but the percentage of methane captured over the life of a landfill can be as low as 20 percent of its emissions.

The best way we can help decrease methane emissions is to compost.  We can think of composting as recycling our organic, decomposable and biodegradable waste into nutrient-rich soil that can be used to fertilize our yards and gardens. The aerobic nature of composting produces very little methane and will decrease the amount of trash that goes into landfills, thereby decreasing methane emissions while providing more space for other trash.

Incinerators dispose of waste by burning trash. Some programs include waste-to-energy plants that burn trash to produce energy in the form of steam and electricity. CO2 and nitrous oxide are two greenhouse gases emitted through waste incineration. Currently, only one incinerator is present in North Carolina.