The Energy Saving Ordinance (EnEV) represent one of the most important instruments of German energy and climate change policy. The new EnEV comes into force in 2017 and will define the German lowest energy standards. This will have impacts on not only public sector new builds, but also on private sector buildings. Critics predict rising costs being passed on to the construction industry.

Background

The 2017 EnEV is the German reaction to current EU legislation - the EU building directive passed in 2010 to be more precise. This stipulates that all 28 member states are to ensure that, within the EU from 2021, all new builds are to be so called nearly zero-energy buildings, meaning that they require almost no energy any more. How exactly this EU wide standard is implemented is the responsibility of the individual states, meaning that the German government is also obliged to introduce suitable regulations in order to implement the law. The EU building directive requires a draft of these regulations by the beginning of 2017. This should take the form of the 2017 EnEV.  Using this opportunity, the country also wants to simplify its energy policy and plans to combine the energy saving regulations with the renewable energies heat act.

Contents

The new energy saving regulations dictate that future new builds adhere to the lowest energy standard. At present, there is a distinction made between public and commercial buildings.  The following timescale is to be used for the implementation of "nearly zero-energy building":
- from 2021 for commercial use buildings,
- as soon as 2019 for public new builds.

A nearly zero-energy building is identified as having a net energy requirement for heating, ventilation, cooling and hot water of almost nil. The technology required to achieve this standard already exists today.  Pilot projects have shown that the majority of concepts are extremely similar: the basis of them are well insulated, compact building envelopes, high internal storage masses and the use of solar gains. Additionally, there is often controlled domestic ventilation with heat recovery which provide warm water through geothermal heat pumps and a thermal solar system. 

A nearly zero energy build can be seen as a precursor to a zero energy house. In a zero energy house, the external energy consumption of the building is completely offset by the average energy gains over the year. If more energy is produced that the house requires, this is known as a plus energy house. If a building requires no external energy at any time, then it is called energy self sufficient. The energy required for the creation (for the construction) of the house is not taken into account in the specifications of the energy standard.

Cost effectiveness

There is often a critical reaction to the announcement of the 2017 EnEV that ascribe the expected significantly increase in building costs or the actual cost increases to the energy policy. The planning and execution of building projects is without doubt more challenging. In developments in neighboring countries such as Denmark as well as the projects that have already been completed in Germany it can however be seen that the concerns about a cost explosion are unfounded in most cases. 
According to the building cost reduction commission, the greatest actual cost drivers in the building branch is the current interaction between supply and demand. There is an ever increasing need for living space, particularly in urban centers where the supply is becoming ever shorter - this is further fueled by low interest rates. This in turn leads to increasing real estate and service prices. The minimum wage or rising public charges also influence the cost of building.

According to findings from the Munich Institute for Thermal Insulation, the latest amendment of the EnEV has increased the cost of construction by an average of 3.2%, however it also led to an approximate reduction in primary energy requirement of 25%. 

If the results of the 2017 EnEV are of a similar magnitude, then this could be classified as being cost effective. Previous experience have additionally demonstrated that there is a learning curve effect relating to the use of building components that occurs some time after the introduction of new laws and standards - the energetically improved building components become more cost effective over time and the costs are regulated again.