The environmental impacts of Hannover Re's business operations are comparatively slight. We nevertheless take our responsibility for the environment very seriously and we define concrete environmental targets and measures in our Sustainability Strategy 2015-2017, which was approved by the Executive Board. With the implementation of our environmental management system, which was certified according to DIN EN ISO 14001 in 2012, we put in place standard processes for dealing with environmental protection and we specified concrete measures in our environmental programme. The recertification of our environmental management system passed off successfully in November 2015. Going forward, we intend to meet the requirement to conduct an energy audit by the yearly publication of an EMAS III accordant environmental statement.
The focus of our efforts to conserve the environment is on reducing CO2 emissions associated with the supply of electricity and heating to our premises as well as those caused by our business travel. We achieved our goal of operating on a CO2-neutral basis at our Hannover location by 2015 to a level of 97% in the year under review. The changeover to renewable energy as well as the offsetting of greenhouse gas emissions resulting from our air travel through the climate protection organisation atmosfair were key factors in this achievement. The 3% that has still to be offset derives primarily from the use of district heating and to a modest extent from paper consumption. Having already converted our power supply at the German location to renewables, we now want to extend this progressively to our international offices as well. In addition, we make every effort to ensure the economical and resource-saving use of materials and raw materials such as paper and water at our offices. We record central consumption and emissions data for our Home Office in Hannover.
Furthermore, Hannover Re dedicates itself to a number of environmental conservation projects, including for example the local initiative Climate Alliance Hannover and the Carbon Disclosure Project (CDP), the international transparency initiative on emissions data.