Calculation Details

Trees planted by the Clear Water Carbon Fund are native species well suited to thrive in the Northeast.  On average, each tree will store at least 570 pounds of carbon dioxide (CO2) over 40 years.  Trees planted by the Clear Water Carbon Fund are planted within 150 feet of streams or rivers or in priority upland areas.  Trees are monitored for 40 years. The cost of Clear Water Carbon Fund's trees include planting and maintenance of trees, periodic monitoring to verify the amount of carbon storage, and monetary incentives to landowners to compensate for the loss of other revenue-generating activities such as the use of these areas for hay. The vast majority of revenue goes towards planting and maintaining trees.

Emissions estimates were derived from standard equations developed by the US Environmental Protection Agency.  We provide offset packages for a variety of different travel distances, transportation types, offices, and events.  More information on these calculations are available below.  If our existing offset packages do not fit your needs, please contact us.  

 

Emission Calculation Assumptions

Household Heating:

 We used annual energy usage data for the Northeast from Energy Information Administration (2005):

Natural Gas

43455 ft3/year

Oil

392 gallons/year

Propane

43 gallons per year

Greenhouse gas emissions calculations were based on calculations developed by EPA (2010):

0.98

lbs/kwh

0.005

MT/therm

22.384

lbs/gallon

12.17

lbs/gallon

Air Travel:

We used methodology outlined in by Putt del Pino and Bhatia (2002) and in the WRI employee commuting spreadsheets.  Short haul flights were assumed to generate 0.289668491 kg of CO2/mile, medium haul flights were assumed to generate 0.202767943 kg of CO2/mile, and long haul flights were assumed to generate 0.177019633 kg of CO2/mile.

Commute:

Car emissions calculations were completed according to methodology developed by EPA (2005). 

Rail and airline emissions were calculated based on methodologies outlined by Putt del Pino and Bhatia (2002) and in the WRI employee commuting spreadsheets.

 We assumed fuel efficiency of 30 mpg for compact cars, 24 mpg for mid-sized cars, 22 mpg for full-sized, 21 mpg for small trucks and SUVs, and 15 mpg for large trucks and SUVs.

Average annual commute calculations were based on travel 5 days a week for 50 weeks a year.

Annual mileage calculations were based on 12,000 miles per year (EPA 2005).

A gallon of gasoline is assumed to produce 8.8 kilograms (or 19.4 pounds) of CO2 (EPA 2005).

 Office

 Office emission calculations are based on methodologies developed by US Department of Energy (2003).

We assumed 250 ft2 of office space per employee (industry standard) and 20 lbs of CO2/ft2 (EPA)

Conferences:

Predominantly local travel assumes: 80% of attendees drive less than 1 hour, 15% drive 3 hours, and 5% travel using a short haul flight

Regional travel category assumes: 30% of attendees drive <3 hours, 30% drive >3 hours, 30% travel on a short haul flight, and 10% travel on a medium haul flight

National travel category assumes: 5% of attendees drive <3 hours, 20% drive >3 hours, 20% travel on a short haul flight, 30% travel on a medium haul flight, 20% travel on a long haul flight, and 5% travel on an international flight.

Conference calculations assumed 1 individual/room

Hotel emissions were assumed to be 29.53kg/CO2/day (Northeast Region Calculations, Energy and Environmental Analysis, Inc., 2005)

Car travel assumes weighted average combined fuel economy of cars and light trucks of 20.4 mpg (FHWA 2008)

Emissions for car travel based on calculations developed by EPA (2005).

Weddings:

Predominantly local travel assumes: 80% of attendees drive less than 1 hour, 15% drive 3 hours, and 5% travel using a short haul flight

Regional travel category assumes: 30% of attendees drive <3 hours, 30% drive >3 hours, 30% travel on a short haul flight, and 10% travel on a medium haul flight

National travel category assumes: 5% of attendees drive <3 hours, 20% drive >3 hours, 20% travel on a short haul flight, 30% travel on a medium haul flight, 20% travel on a long haul flight, and 5% travel on an international flight.

We assumed 2 individuals per hotel room.

Hotel emissions were assumed to be 29.53kg/CO2/day (Northeast Region Calculations, Energy and Environmental Analysis, Inc., 2005)

References:

Energy and Environmental Analysis, Inc. 2005. CHP in the Hotel and Casino Market Sectors.  Prepared for the Environmental Protection Agency CHP Partnership.

Energy Information Administration (2005) Residential Energy and Consumption Survey: Energy Consumption and Expenditures Tables

EPA (2005) Emission Facts: Greenhouse Gas Emissions from a typical passenger vehicle.  U.S. Environmental Protection Agency, Office of Transportation and Air Quality, Washington, DC., U.S. EPA #420-F-05-004.

EPA (2010) Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2008. Annex 2 (Methodology for estimating CO2 emissions from fossil fuel combustion), P. A-75. U.S. Environmental Protection Agency, Washington, DC. U.S. EPA #430-R-10-006

Department of Energy, Energy Information Administration’s 2003 Commercial Building Energy Consumption Survey (CBECS).

Putt del Pino, S. and Bhatia, P. (2002) Working 9 to 5 on Climate Change: An Office Guide.  World Resources Institute.