The Theory Behind Carbon Offsets

GHG emissions are a global problem. Carbon offsets operate on the idea that any reduction in any area is worthwhile. Yet it's much cheaper to reduce or absorb emissions in developing or transitional regions of the world. Currencies might be weaker or supplies less expensive. Logistically, it is easier to make changes in an area that does not already have a developed infrastructure.

wind power
© Photographer: Philip Lange | Agency: Dreamstime
Carbon offsets help support renewable energy sources like wind power.

Offsets, however, are somewhat of a luxury. You are, after all, paying for non-emissions -- something that doesn't even exist. Because of this, most people who purchase offsets live in developed nations where drastically lowering domestic emissions is difficult and expensive. A business or household might find buying offsets more economical than retrofitting a building or eliminating auto emissions. With the planet as a whole producing about 25 billion tons of CO2 per year [source: Clean Air-Cool Planet], it doesn't really matter if a reforestation project in Ecuador gets its funding from an Ecuadorian banker or an American factory.

Carbon offsets fund projects like forest planting, conversion to renewable energy sources or GHG collection and sequestration. Offsets support both large-scale and community projects. A single company might restore a forest in Uganda and support the construction of efficient stoves in Honduran villages.

But can carbon neutrality really be bought? We'll learn all about retail carbon offsets and why people buy them in the next section.

Money for Nothing
Greenhouse gases trap heat in the Earth's atmosphere. Cars, planes, power plants and factories all emit GHG. The Kyoto Protocol, an international GHG agreement, defines six troubling types of emissions:

  • Carbon dioxide (CO2): When fossil fuels, waste and plant matter burn, they emit CO2, the most common GHG emission.
  • Methane (CH4): Landfills, livestock, agricultural activities and the production of coal, natural gas and oil all generate CH4, an emission far more powerful than CO2.
  • Nitrous oxide (N2O): Sewage treatment and the combustion of fossil fuels both produce N2O. However, fertilizer and agricultural soil management release the majority of this potent emission.
  • Sulfur hexafluoride (SF6): The electric power industry uses this man-made compound for insulation and current interruption.
  • Hydrofluorocarbons (HFCs): Solvents, refrigerants, firefighting agents and propellants for aerosols use HFCs as a replacement for ozone-depleting chlorofluorocarbons (CFCs).
  • Perfluorocarbons (PFCs): There are relatively low amounts of PFCs in the atmosphere,­ but they're hard to get rid of. The estimated atmospheric life of this solvent and component of aluminum production ranges from 10,000 to 50,000 years! [source: National Center for Biotechnology Information­]

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