Hi Ray,

That’s a big question!

One could start with the energy savings and calculate the CO2 savings based on where and how the electricity is produced (local coal or renewable energy or nuclear etc.) Here is the link to the EPAs greenhouse gas calculator. A coal fired power plant in the northeast has more related CO2 emissions since the coal must be shipped in. This process could be repeated for the building materials, transportation, water and so on.

LEED 2009 started addressing that issue and incorporated TRACI as an alternative compliance option. I have not seen this method used and there is little information on its implementation.

The U.S. EPA has developed TRACI, the Tool for the Reduction and Assessment of Chemical and other environmental Impacts.

There is so much info that this link would only get you started: http://www.epa.gov/nrmrl/std/sab/traci/

You may also use the LEED NC 2009 Credit Weighting Matrix Tool that calculates CO2 emissions, which may be helpful.

Related Advice:

• China co2 Emissions: Can We Really Prevent Global Warming?