|
Carbon offsets are funds that are used to mitigate the impacts of greenhouse gas (GHG) emissions by channeling corporations’ and individuals’ voluntary investments into projects that create carbon dioxide (CO2) savings equivalent to their CO2 emissions. Companies and individuals can opt to purchase carbon offsets from companies or organizations that direct these funds toward carbon-offsetting activities to eliminate or reduce environmental impacts associated with carbon-emitting activities.
Consumption of electricity is the largest generator of GHGs, and more than a fourth of U.S. GHG emissions are generated by travel. In addition, business travel accounts for the largest percentage of travel-related emissions; 47 percent of passengers on U.S. domestic flights are traveling for business. Buildings account for the majority of U.S. electrical consumption. Although these activities can be reduced through efficient building renovations and conservation practices, companies often seek to offset remaining emissions that cannot be controlled or further reduced.
There are three types of carbon-offsetting projects: projects that prevent the release of CO2, projects that reduce non-CO2 GHGs, and projects that sequester carbon in vegetation, soil, and/or geologically.
CO2 Prevention
Preventing the release of CO2 before creating emissions is the most important precursor to carbon offsetting. This can be accomplished by analyzing emissions-producing activities and developing a reduction plan. Contributors can include energy, transportation (i.e., shipping, fleet, commuting, sourcing), materials (i.e., paper, office supplies, furniture, vehicles), and events.
Non-CO2 GHG Reduction
Non-CO2 GHGs significantly contribute to climate change; approximately 30 percent of human-induced GHGs are non-CO2 GHGs. Non-GHGs include methane (CH4), hydrofluorcarbon
(HFC), perfluorcarbon (PFC), and sulfurhexafluoride (SF6). Non-GHGs are generated from petroleum systems, natural gas systems, landfills, manure management, electric power systems, semiconductor manufacturing, and refrigeration/air-conditioning use. Reductions in non-CO2
GHG emissions from energy and agriculture would result in the greatest global mitigation. Methane has the largest potential for reduction. Non-CO2 GHGs are less expensive to reduce than CO2. They can be reduced by improving the efficiency of the above-mentioned systems, which will in turn minimize the CO2 emissions from source energy and building energy consumption.
Carbon Sequestration
Carbon sequestration is the process through which agricultural and forestry practices remove CO2 from the atmosphere. The term “sinks” is also used to describe agricultural and forestry lands that absorb CO2. Sequestration activities can help prevent global climate change by enhancing carbon storage in trees and soils.
Investing in Carbon Offsets
By purchasing carbon offsets, companies can voluntarily invest in sequestration or energy-efficiency projects that absorb or prevent the release of a tonnage of CO2 equivalent to their carbon footprint. Other carbon-offset programs invest in renewable energy or clean energy technologies (e.g., wind power). Companies such as TerraPass invest in capturing methane gas in farming practices, and other programs promote industrial efficiency.
Carbon offsetting can also allow companies to counterbalance their carbon emissions through projects that are less costly than internal or direct emissions reductions. Other ancillary benefits to carbon offsets include economic development, spurred in communities in which offsetting projects take place, as well as positive publicity for companies marketing their socially and environmentally responsible practices. |