New opportunities & obligations: Changes to the Building Energy Act 2023

The Building Energy Act (GEG) 2023: Changes, heating inspection, biomethane and subsidies. Find out everything about requirements and exemptions now!

Summary: What is the Building Energy Act (GEG)?

The GEG serves the national enforcement of the European Buildings Directive(EPBD) and the Energy Efficiency Directive(EED). Since it came into force in 2020, the law has gone through many iterations and was last amended on 16.10.2023. According to the GEG 2024, the changes came into force in 2024 and deal with the optimization of older heating systems (§60b), which must be checked and optimized by 2027 if they were built before 2009, younger systems must be checked every 15 years. Parameters such as efficiency and thermal insulation are optimized.

When does the EnEV apply and when does the GEG apply?

The Energy Saving Ordinance (EnEV) and the Energy Saving Act (EnEG) were passed in 2005 and 1976 and were valid until November 1, 2020. Since then, they have been replaced by the Building Energy Act (GEG), so the EnEV and EnEG are no longer valid.

Can biomethane be used to comply with the Building Energy Act?

For buildings to be constructed, there is a requirement that they must be nearly zero-energy buildings. Nearly zero-energy buildings must only require a maximum of 0.55 times the annual primary energy requirement (_QP) of a reference building and comply with maximum heat loss values. This corresponds to a heat consumption of less than 75 kWh/m²a and an energy efficiency class B or around 1/10 of the consumption of an average 1950s building(bauhandwerk.de). The _QP is calculated using DIN V 18599: 2018-09. For this purpose, the final energy consumption is calculated as shown below and multiplied by the primary energy factor.(energie-experten.org) The primary energy factor merely refers to the energy source used, as explained below.

Achieving the annual primary energy requirement using renewable energies

One means of achieving the required annual primary energy demand is the use of renewable energies. For this purpose, the primary energy factor is used, which is 1.1 for fossil fuels and, depending on how biomethane is used, is set at 0.7 (boiler) or even 0.5 (high-efficiency CHP plant).

Biomethane is renewable methane that is produced by processing biogas from organic materials such as agricultural waste and sewage sludge. You can read more about this in the blog on biomethane(agriportance.com).

Illustration of DIN V 18599 - Energy assessment of buildings

One means of achieving the required annual primary energy demand is the use of renewable energies. For this purpose, the primary energy factor is used, which is 1.1 for fossil fuels and, depending on the heating of biomethane, is taken into account with 0.7 (boiler) or even 0.5 (highly efficient CHP plant).

The amount of biomethane used must be verified using a mass balance system and must also meet the requirements of the EEG 2009 in Annex 1(EEG 2009).
As broken down in the Dena guidelines, a heating system that is operated with 65% renewable energy from biogas (i.e. biomethane) is a flat-rate compliance option. This means that an individual calculation in accordance with DIN V 18599 is not necessary.
Verification is primarily carried out via the Dena biogas register. The responsible authorities are state-specific, in NRW it is the building supervisory authority(GEG-UG NRW).

To which buildings does the Building Energy Act apply?

The Building Energy Act obliges owners of both new and existing buildings to comply with energy-specific criteria. It also stipulates requirements for possible subsidies, which are implemented at state level. The law applies to all buildings that are heated or cooled according to their intended purpose.

Exceptions: To which buildings does the GEG not apply?

All buildings are subject to Section 3 of the GEG, which deals with the inspection of air conditioning systems. However, the following buildings are not subject to the rest of the law:

• Business buildings that are primarily used for animal breeding or husbandry
• Buildings that have to be kept open over a large area and for long periods of time depending on their intended use
• greenhouses
• Tents and temporary buildings with a planned useful life of less than 2 years
• Religious buildings
• Underground buildings
• Residential buildings that are used for less than 4 months per year
• Residential buildings whose annual useful life is limited, resulting in an energy consumption of less than 25% of the expected value
• Commercial buildings that are heated to less than 12 degrees Celsius according to their intended use
• Commercial buildings that are heated for less than 4 months and cooled for less than 2 months

What are the penalties?

The owners or builders of a building are responsible for complying with the regulations. They are therefore also liable for fines of up to €5,000 in the event of non-compliance with the energy requirements.

How is the subsidy regulated according to the Building Energy Act?

The GEG also states that renovated or newly built systems that generate heat from biomass (including biomethane) are eligible for funding. You can find more details on the funding program at the Federal Office of Economics and Export Control (BAFA) in the program for federal funding of efficient buildings (BEG).

Summary of the program

The Building Energy Act (GEG) 2023 brings comprehensive changes for new and existing buildings and replaces previous regulations such as the EnEV and the EnEG. It requires the optimization of heating systems, promotes and regulates the use of renewable energies such as biomethane and sets new standards for energy-efficient construction. The law also provides for sanctions in the event of non-compliance and offers funding opportunities for sustainable energy projects.