By improving facilities and operational efficiencies and generating or purchasing electricity from renewable resources, emissions from electricity decreased by 35 tons last year. Overall emissions from energy as indexed to revenue decreased by 4% in 2011 and 25% since 2008.
In 2011, we enhanced the efficiency of heating, ventilation and air conditioning systems because these systems are primary consumers of energy at the Agora building (Madison, WI, USA). We replaced variable frequency drives on boilers at the Agora, reducing the number required for that building from three to one. We also made changes to the chiller filters and replaced chiller motors. These changes will enable one chiller to run during peak periods instead of two, and may allow only fan usage during winter.
In 2011, we continued to increase use of renewable energy. On the aviation operations building in Madison, WI, USA, 250 photovoltaic panels generated over 110,000 kWh, avoiding over 60 tons of CO2 generation. Promega distribution hub in Mannheim, Germany, and San Paulo, Brazil also started using 100% renewable energy sources in 2011.