Energy efficiency and reduction of emissions
Deutsche Wohnen’s energy management activities for its portfolio and new construction projects are currently taking a two-pronged approach – with an unerring focus on greenhouse gas emissions. Firstly, we supply our properties with environmentally friendly power. We use renewable energy and supply three quarters of our existing residential units with heat or fuel from our joint venture G+D. Secondly, we are investing heavily in the energy efficiency of our apartments and facilities. We have been paying particular attention to the energy efficiency of our properties for a number of years. In terms of energy consumption, approximately 74.5% of our units already perform better than the average residential property in Germany (160 kWh/sqm per annum).^a) Some 27% of our units use less than 100 kWh/sqm per annum (A+ to C). The average consumption of our holdings stands at 133.4 kWh/sqm per annum, having fallen again slightly as compared to the previous year (2016: 135.1 kWh/sqm per annum). 

In addition, we collect data on the absolute consumption of heating energy and electricity at our holdings and calculate the corresponding carbon emissions. We view these in relation to the gross internal floor area and check efficiency.

The listed units are also included in these figures. Due to the legal requirements in place, it is impossible to improve the energy efficiency of listed properties to the same extent as that of non-listed buildings by means of modernisation work. Furthermore, the figures for 2016 and 2017 are only comparable to a limited extent because they draw on absolute consumption data based on reference values that vary slightly due to the different invoicing periods used by suppliers. In relation to our total portfolio as of 31 December 2017, the heating energy consumption was calculated for around 85% of the portfolio, while electricity usage was determined for some 89%.^b) As we did not undertake any new construction work in the year under review, no consumption was recorded in this area. 

We have initiated an extensive investment programme for the maintenance, refurbishment and modernisation of our property holdings with a view to energy conservation. By 2022, we will invest more than EUR 1.2 billion in insulating facades, basement ceilings and roofs, improving the standard of fixtures in our residential units, replacing windows or making them more energy-efficient, renewing heat generation plants and utilising regenerative or efficient means of energy generation. In doing so, we will meet the requirements of the German Federal Emission Control Act (Bundes-Immissionsschutzgesetz – BImSchG) and the Energy Saving Ordinance (Energieeinsparverordnung - EnEV).

With our investments in comprehensive modernisation work within our portfolio, we have refurbished a total of around 3,000 residential units in the past three years (2015–2017) with a view to energy conservation. As a result, final energy requirements have improved by an average of approximately 35% to 103 kWh/sqm per annum, which corresponds to annual energy savings of approximately 8.2 million kWh or 2,000 t of CO₂. In 2017, a number of holdings in Berlin, Hanover, Braunschweig, Dresden and Mainz benefited from our refurbishment work with a view to energy conservation. Some of these projects had to comply with heritage protection regulations. The work included improving insulation, fitting double-glazed windows and repairing facades, for instance. We also modernised kitchens and bathrooms and added balconies. 

Detailed information on climate-relevant emissions and the basis of calculation can be found in the following performance indicators reported for Criterion 13. 

^a) The Energy Performance Certificate: Specifications for Residential Buildings (Der Energieausweis: Steckbrief für Wohngebäude), https://www.verbraucherzentrale.de/Der-Energieausweis-Steckbrief-fuer-Wohngebaeude-4, accessed on: 20 April 2018. Average figures take account of energy requirements for heating and generation of hot water. No energy performance certificate is required for approximately 30,000 units which are listed.
^b) In addition to the absolute consumption figures, we published further data, including like-for-like key figures on the energy usage of the portfolio and our administrative locations, as part of our reporting in accordance with the EPRA Best Practices Recommendations on Sustainability Reporting (EPRA sBPR) in July 2018.