HOW TO CONNECT SECTORS

The German federal government has set itself the goal of reducing greenhouse gas emissions by 80 to 95 percent by 2050, compared to 1990 levels. In order to reach this goal, the use of fossil-based energy resources must be reduced to practically zero and, conversely, the proportion of renewable energies must be massively increased. With the exception of biomass and solar thermal energy, renewable energy sources are mainly available in the form of electric energy generated by wind turbines and photovoltaic systems.

Our energy system has traditionally been divided into three sectors: mobility, heating, and electricity. These sectors are supplied by a variety of energy sources. Mobility is primarily supplied by oil; heating primarily by natural gas, but also by oil, coal, renewable energies, and electricity; and electricity by coal as well as renewable energies, nuclear energy, and natural gas. The heating and mobility sectors are not greatly electrified today, but when they start to rely much more on electrical energy in the future, it will no longer be possible to sustain the traditional separation of the three sectors.

However, these sectors also offer the possibility of using flexible loads to cushion the fluctuations in supply that naturally occur when the sun and the wind are used as energy sources. So far, this cushioning has been done to a small extent through electric night storage heating systems, which transform surplus electrical energy from nuclear and lignite-fired power plants into low-temperature heating at night. In the future there will be a stronger focus on similar systems, such as those that charge electric vehicles with renewable energy during periods when there is an energy surplus. As a result, electric energy is becoming a link for connecting sectors that generally used to be separate.

The important role that this link between the sectors will play in the success of the energy transition was recently emphasized by a position paper and analysis that was part of the Academies’ Project “Energy Systems of the Future.”* This study concludes that the direct use of electric energy in the mobility and heating sectors will be considerable—and that it will also be the least expensive, as a rule. Conversely, synthetic fuels for vehicles and heating will play a significant role in a future energy system that will largely depend on renewable sources.

This prediction involves an economic sector that has not been mentioned before in this connection: the chemical sector. The chemical industry is a relatively insignificant consumer of oil, which is its key raw material. It consumes less than ten percent of the total oil produced. The decreasing use of oil as a source of energy poses two challenges to the chemical industry—but at the same time, these challenges could help it to open up new areas of business. Firstly, in the future oil as a raw material may not be available for many production processes in the same amounts or at the same levels of quality and prices as in the past. As a result, the chemical industry will have to find other production routes. Secondly, the increasing incorporation of electrical energy into chemical production processes will make available an additional component of value creation: the function of balancing loads in an energy system that is largely based on a fluctuating supply of electrical energy.