I am working with a local hotel to calculate their total CO2emissions per year. Can you
help me convert electricity used by the hotel, measured in kWh, to total CO2 emissions,
depending on their source of electricity?
Since you are in the Seattle City Light service territory, I posed this question to the
manager of the Global Warming program for that utility. I was told these numbers are tricky because of the mix of generation resources used to
provide electricity on an annual basis for a utility. Seattle City Light reports
this information as it relates to their energy conservation programs. They state that the
kWhs saved are produced from combustion gas turbines, not the predominate hydro power
base. For conserved energy, you can safely use 0.392 metric tons per MWH or 0.0865 pounds
per kWh. On a regional and statewide basis the number would be less because of the
weighted influence of the hydro base.
Carbon Calculation Resources
The following calculator performs simple electricity(or other fuels)-to-carbon calculations. I found carbon calculators at EPA and other sites, but they are specifically for calculating individual energy use and carbon production ("How many bags of garbage do you put out each week," etc.).
- National Energy Foundation: Energy to Carbon converter. Scroll to "The Calculator." This calculator is British, so some types of calculations require simple conversions from metric units.
These may be useful in unit conversions:
Energy Star. Portfolio Manager.
Mother Earth News. How to Calculate Your Office Building's Carbon Emissions.