With a view to further cutting our energy consumption at the Hannover location, we systematically pressed ahead with the already existing measures and initiated some additional steps in the year under review. For example, the staff canteens at our main offices were thoroughly renovated in the years 2016-2018 and fitted out with new equipment and technology. This enabled us to optimise production processes in the kitchen and boost energy efficiency.
In 2017 we handed over operation of the backup data centre – which we had previously run ourselves – to a professional data centre operator. The "shared" data centre fulfils the Platinum level of LEED (Leadership in Energy and Environmental Design) certification and is powered entirely by renewable energy. The relocation also makes it possible to achieve a significantly lower PUE (power usage efficiency) ratio than is possible in comparable self-operated facilities. The PUE metric denotes the ratio of the total amount of energy used by a computer data centre to the energy delivered to computing equipment and it thus determines the efficiency of the data centre's energy usage. This increased efficiency thus results in a further considerable energy saving.
We are also making increasing use of state-of-the-art communication capabilities in order to conserve resources in our work. Our standard workplaces have been made more energy-efficient and hence more environmentally friendly. Notebooks, PCs and workstation printers with high energy consumption and CO2 emissions were replaced with more modern energy-efficient devices. With the realisation of the aforementioned measures, the IT project to restructure and optimise PC workplaces ("Next Generation Workplace") has been completed.
At the beginning of 2012 we made a complete changeover in our electricity supply and have since used power from our external energy providers that is obtained exclusively from regenerative sources. Electricity consumption in the year under review, including self-generated solar energy, stood at 8,825,131 kilowatt hours. This is equivalent to a reduction of roughly 2% (previous year: 9,008,650 kilowatt hours). The decrease can be attributed inter alia to the comparatively mild summer temperatures, which reduced the need to run air-conditioning for the data centre.
In November 2013 we installed altogether 652 solar modules on the roof of the office buildings in Hannover. In the 2017 financial year 106,151 kilowatt hours of solar energy were generated through operation of the system, roughly equivalent to the power consumption of 41 two-person households.
Electricity consumption per employee was lower than in the previous year at 6,372 kilowatt hours (previous year: 6,678 kilowatt hours) and significantly below the five-year average.
Our district heating consumption in 2017 was significantly lower than in the previous year at 2,946,370 kilowatt hours (3,386,632 kilowatt hours adjusted for weather conditions).
In 2015 we modernised the glass facade of our main office building at Karl-Wiechert-Allee 57 and installed a weather-based, proactive heating management system. Analysis of the district heating consumption data shows that these measures have reduced consumption – adjusted for the effects of weather conditions – by 512,495 kilowatt hours since 2016 compared to the base year of 2014. This is equivalent to cutting CO2 emissions by 42.7 tonnes.