Sector coupling at system level

What to do with the ever increasing quantities of electricity from wind and solar that do not always find takers? This key question needs to be answered in order to initiate the next stage of the energy transition. A key approach to solving this issue is to divert this electricity to other sectors – where large amounts of energy are also required. This is technically possible by coupling the existing infrastructures of the German electricity and gas system with each other. Power-to-gas systems act as a bridge between the individual systems. They enable electricity to be transformed into hydrogen – an important raw material and environmentally friendly energy source that can be used in all sectors. The same applies to synthetic methane, which in turn can be obtained from hydrogen.

Until now, the transformation and transport of energy has always taken place within each system separately. For example, electricity transport: Power plants feed electricity into the grid. This electricity is then transmitted via transmission lines, passed on to other voltage levels via current transformers and transported on from there to the end customers. Gas transport works in a similar way – from the transport network via the regional network to the distribution network. The power-to-gas approach opens up the option of transporting energy between sectors as well. Here, electricity is converted in the power-to-gas system – the “sector transformer” –, into hydrogen fed into the gas system and transported on to the respective point of consumption.