At the beginning of 2012 we made a complete changeover in our electricity supply at our Hannover location and have since used power from our external energy providers that is obtained exclusively from regenerative sources. In November 2013 we installed altogether 652 solar modules on the roof of the office buildings in Hannover. In the 2018 financial year 92 megawatt hours of solar energy were generated through operation of the system, roughly equivalent to the power consumption of 40 two-person households.
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.
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.
In the years 2016-2018 the staff canteens at our main offices were thoroughly renovated and fitted out with new equipment and technology. This enabled us to optimise production processes in the kitchen and boost energy efficiency. We are also making increasing use of state-of-the-art communication capabilities. 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. We are now working to progressively install a smart LED lighting control system in our offices and to reduce stand-alone local printers.
Electricity consumption in the year under review, including the roughly 92 MWh of self-generated energy from our photovoltaic installation, stood at 7,123.23 megawatt hours. This is equivalent to a reduction of around 19.4% (previous year: 8,825.13 megawatt hours). The decrease can be attributed inter alia to the modernised canteens and the removal and outsourcing of the data centre as well as the elimination of the associated cooling technology.
Electricity consumption per employee was lower than in the previous year at 4,967 kilowatt hours (6,372 kilowatt hours) and significantly below the five-year average. Our goal is to cut the electricity consumption per employee by 10% relative to 2017 by the year 2020.
|Purchased electricity (from renewable sources)||7,031.28||-19.4%||8,718.98||8,886.20||8,745.61||8,824.98|
|Solar power (self-generated)||91.95||-13.4%||106.15||122.45||122.74||145.00|
|Proportion of solar power||1.3%||+0.1%-point||1.2%||1.4%||1.4%||1.6%|
Our district heating consumption in 2018 was lower than in the previous year at 2,932.68 megawatt hours (3,333 megawatt 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 around 706 megawatt hours since 2016 compared to the base year of 2014. This is equivalent to cutting CO2 emissions by 60.3 tonnes.
Our goal is to reduce the consumption of heating energy – adjusted for the effects of weather conditions – by 5% per employee by the year 2020 compared to 2017.