In the German climate action package 2030, a national price for greenhouse gas emissions in the transport and building sectors was introduced. However, the effect of such a price is unclear considering the influence of economic effects on the investment decisions of households. Accounting for these aspects, we analyze the effect of price signals by coupling econometric modeling of final energy consumption and linear techno-economic optimization of the energy system. In doing so, the feedback effects of consumer behavior and a carbon price floor are incorporated into the energy system model.
The introduction of a CO2 price for households influences the investment behavior, leading to the adoption of more electricity-based technologies. Compared to our reference scenario, significantly more electric vehicles are purchased, and heat pumps installed. In the electricity sector, the introduction of a carbon price floor leads to a greater decarbonization of power generation, which is reflected in a stronger expansion of renewable energy capacities. In addition, the energy sector, in contrast to the building, traffic, or industry sector, contributes disproportionately to greenhouse gas reduction due to the minimum price, such that the national reduction target of 55% will be achieved in 2030. In 2050, however, the climate targets will only be achieved in a scenario with a high CO2 price. Yet, this is not based on an intensified transformation in the transport and building sectors, but on the provision of imported CO2-neutral synthetic energy sources.