metric tons x Electricity and fuel use (1,000 MMBtu) Calculated with grid emissions factors Reduced by the CO2 avoided by renewable electricity purchases 2014 20,842 2,092 1,842 2013 21,190 2,186 1,962 2012 21,613 2,404 2,195 2011 21,758 2,397 2,182 2010 21,622 2,426 2,156 IBM uses the Greenhouse Gas Protocol: A Corporate Accounting and Reporting Standard, developed by the World Resources Institute and the World Business Council for Sustainable Development, for estimating and reporting its CO2 emissions.