The future role of Power-to-Gas in the energy transition: Regional and local techno-economic analyses in Baden-Württemberg

This paper analyses the potential of the Power-to-Gas (PtG) concept in Baden-Württemberg (BW), south west Germany. A macroeconomic analysis shows that a cost-covering operation of PtG for hydrogen production is first possible under our assumptions in 2030. Previous model-based analyses for Germany identified locations, mainly in north-west Germany, where these plants could achieve these full load hours and thus be economical in the future energy system by 2040. Importantly, although some short-term storage devices (batteries) are installed in BW in this scenario, no PtG plants are seen at the level of the transport network. A more detailed analysis for BW at the municipality level develops residual load profiles for individual 110 kV transformers and municipalities. A very large increase in the residual load profiles in the north-east of Baden-Württemberg by 2040 is encountered, suggesting a requirement for network strengthening and local storage, including PtG, in this area. Four very different and representative model regions are further analysed, whereby only Aalen, a region with large wind potentials in the north east of BW, is identified as having significant potentials for PtG by 2040 (between 69 and 155 MWel). The current restrictions for injecting hydrogen into the gas network (2–10% by volume) mean that these PtG plants would have to incorporate a methanation step in order to upgrade and feed in SNG. The generation of SNG on a local level is therefore expected to be an option by about 2040, if the development of renewable energy generation proceeds as quickly as expected in the current energy-political scenario explored here. The existing CO₂ sources for methanation are not located in the vicinity of the expected PtG plants, so that a CO₂ separation from the air and/or a liquefied transport could be most economical. Further work is required to consider the local energy infrastructure, especially electrical and gas distribution networks.