The Prognos business-as-usual scenario

Will a district or federal state achieve its climate targets? How much action still needs to be taken? To help our customers answer these questions, Prognos has developed a business-as-usual (BAU) scenario that describes the development of the energy system in Germany up to 2045.

The scenario takes into account the energy and climate protection instruments introduced for Germany up to autumn 2023. The aim is to check whether the climate protection and energy efficiency targets will be achieved with the federal instruments already decided upon – and to determine how large any target gaps are.

Profile of the BAU scenario

• The BAU scenario is a reference scenario that takes into account the instruments introduced by autumn 2023. It continues the development of the German energy system under these conditions (projection).
• Instruments that are under discussion but have not (yet) been decided upon are not taken into account.
• The sectors are classified in accordance with the Climate Protection Act (Klimaschutzgesetz, KSG). This allows a comparison with the sectoral targets for 2030 that are enshrined in law.
• The BAU scenario is not a target scenario – it examines whether the climate protection targets can be achieved with the instruments that have already been decided upon and, if necessary, how large the target gap is. However, no adjustments are made by means of additional instruments to ensure that the targets are achieved.
• The BAU scenario is not a forecast.
• Current assumptions about framework data are used, including assumptions about population and economic development and global market energy prices. These assumptions are taken from exogenous sources, including current statistics and stock market prices.
• The statistical margin is the year 2022.

The BAU scenario includes the following instruments, among others:

• Fuel Emissions Trading Act (BEHG)
• Emissions Trading System (EU ETS)
• Federal funding for energy and resource efficiency in the economy (EEW)
• Renewable Energy Sources Act (EEG)
• CO₂ emission standards for passenger cars and commercial vehicles
• Building Energy Act (GEG)
• Federal funding for efficient buildings (BEG)
• National hydrogen strategy
• Energy and electricity tax
• Abolition of the EEG surcharge
• Minimum efficiency standards (EU Ecodesign Directive)

Specific results: Development of greenhouse gas emissions in the BAU scenario

• In the energy sector, both the target for 2030 and the target for cumulative greenhouse gas emissions in the period 2021-2030 will be achieved.
• In the industrial sector, the 2030 sector target will be approximately achieved, and the target for cumulative emissions in the period 2021-2030 will be achieved. This is due, among other things, to low greenhouse gas emissions in 2022 and 2023.
• In the building and transport sectors, both the targets for 2030 and the targets for the period 2021-2030 will be missed, with the transport sector in particular expected to fall well short of its target.

Regionalisation of the BAU scenario to federal states and districts

In a supplementary step, the energy consumption and greenhouse gas emissions of the individual sectors are allocated to the districts and federal states. This is done on the basis of regional framework data and statistics, so that local specifics can be taken into account. In this way, the BAU scenario can be regionalised and statements made about the individual target achievement of a district or federal state.

Links and downloads

Assumptions and results of the BAU scenario (PDF, in German)

Project team: Alex Auf der Maur, Andreas Brutsche, Dr Andreas Kemmler, Dr Almut Kirchner, Sven Kreidelmeyer, Paurnima Kulkarni, Sebastian Lübbers, Dr Alexander Piégsa, Aurel Wünsch, Inka Ziegenhagen

Last update: 12.12.2025