A greenhouse gas emissions inventory is an accounting of the amounts and sources of emissions of greenhouse gases attributable to the existence and operations of an institution. The completion of such an inventory provides an essential foundation for focused, effective outreach on the issue of climate change at a college or university, and the basis for institutional action to address it—in other words, it is a crucial first step toward comprehensive campus climate action efforts.

Clean Air-Cool Planet offers a Campus Greenhouse Gas Emissions Inventory Calculator, an MS- Excel-based spreadsheet tool, for use in completing these activities. The Calculator takes you through the three steps, providing procedural protocols and a framework for investigation . The spreadsheets, based on workbooks by the Intergovernmental Panel on Climate Change (IPCC) for national inventories, have been adapted for institutional use.

The major emission source categories are on-campus energy production, purchased electricity, transportation, waste, agriculture and refrigerants. Looking at the emissions levels in each of these categories provides a good idea of the best opportunities for emissions reduction. Step 3 of this toolkit, Create a Plan, provides an in-depth exploration of options for emissions reductions in each of these categories and subcategories.

But before identifying specific reduction measures, it's important to take another step - Set a Target for overall institutional reductions.

Take a look at the results of completed inventories:

• Smith College recently completed their first "Greenhouse Gas Emissions at Smith College: A Comprehensive Inventory from 1990-2004 and Suggestions for Future Emissions Reductions."
• University of New Hampshire ( Durham Campus) Greenhouse Gas Emissions Inventory The original project that ultimately became the Clean Air-Cool Planet Campus Greenhouse Gas Emissions Inventory Calculator!
• Summary of Energy Consumption and Greenhouse Gas Emissions at Middlebury College, also completed with the use of CA-CP's Calculator tool by Doug Dagan ('03), in support of the comprehensive carbon reduction recommendations to Middlebury's Environmental Council
• Tufts University 's GHG Emissions Inventory for 1990 and 1998
• Harvard University 's Greenhouse Gas Emissions Inventory
• A Methodology for Assessing MIT's Energy Use and Greenhouse gas Emissions.
• The College of Charleston's Greenhouse Gas Audit