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Carbon Footprint—Envir onmental Benefits and Emission Contr ols 109

other emissions for a number of industries are available at Web site of the World Business
Council for Sustainable Development (www.ghgprotocol.org).

Greenhouse Gas Emission Calculators
Several GHG emission calculators are available. Some of these calculators are discussed
below. The scope of these calculators varies from very general and basic calculations to a
variety of more complex calculators for business and industrial sectors. These calculators
can be used for estimating baseline emissions of GHG for the existing facilities as well as for
the potential GHG emissions from the fuel consumed if the facility considers using a CHP
system. These calculators, however, do not estimate the fuel consumed by a CHP facility.
These estimates have to be made separately using other tools discussed in Chap. 8.

U.S. EPA GHG Equivalency Calculator
The U.S. EPA GHG Equivalency Calculator, developed by for the U.S. Environmental Protec-
tion Agency, is available at http://www.epa.gov/cleanenergy/energy-resources/calcula-
tor.html. It can be used for estimating emissions from the use of purchased electricity and
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natural gas. It uses the factor of 7.12 × 10 metric tons CO per kWh, which is the 2005 U.S.
2
national average emission during nonbaseload operations. For emissions in subregions
during nonbaseload as well as baseload periods, the use of the eGRID Web site (http://
www.epa.gov/cleanenergy/energy-resources/egrid/index.html) is recommended. The
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basis used for GHG emissions from using natural gas is 5 × 10 metric tons of CO per
2
therm. It assumes average heat content of natural gas is 100,000 Btu/therm and that its
carbon content is 14.47 kg/10 Btu and that combustion is 100 percent complete.
6
U.S. EPA Office Carbon Footprint Calculator
The U.S. EPA Office Carbon Footprint Calculator, developed in 2008, is applicable to a
variety of office sizes, locations, and types. It not only estimates emissions, it also pro-
vides suggestions for reducing emissions of GHG. It can be used for benchmarking and
performance improvements. It accounts for emissions from three types of sources:

1. Owned or controlled by the business
2. Purchased electricity, heat, and/or steam
3. Indirect sources such as waste disposal and purchased materials
This calculator can be downloaded from the following URL: www.epa.gov/epawaste/
partnerships/wastewise/carboncalc.htm.
Clean Air Cool Planet Campus GHG Calculator
The Clean Air Cool Planet Campus GHG Calculator is designed to aid schools that have
completed greenhouse gas inventories in developing their long-term, comprehensive
climate action plans based on those inventories. It facilitates analysis of carbon reduc-
tion options, project payback times, net present value, cost per ton reduced, and other
relevant markers. This calculator can be downloaded from the following URL: http://
www.cleanair-coolplanet.org.

World Resources Institute’s Industry and Office Sector Calculator
The World Resources Institute’s (WRI’s) Industry and Office Sector Calculator has been
developed in partnership with the Business Council for Sustainable Development.