Power-to-X
I could argue that the chemical industry is a driving force of the Power-to-X panacea if 70% of hydrogen usage is dedicated to the production of ammonia and methanol and the electrification of high temperature heat is a key element of the chemical industry decarbonisation roadmap. Nonetheless, the reality is not so powerful yet, the development of PtX industrial applications is a recent trend of the 2020´s that needs to pick up momentum to ensure economies of scale and efficiencies are developed when enough renewable energy is massively available.
Alternatives:
Power-to-Heat (PtH)
Power-to-Liquid (PtL)
Power-to-Gas (PtG)
Power-to-Power (PtP)
But let´s start from the beginning. At the heart of most Power-to-X concepts is the utilization of renewable electricity to produce hydrogen through the electrolysis of water. This hydrogen can be used directly as a final energy carrier or it can be converted into synthetic fuels, which can then be used in other sectors or be stored until needed.
Basically, without getting into the technicalities behind the different technologies, when electricity is converted into gases like hydrogen or methane we call these technologies Power-to-Gas and when it is turned into liquids like methanol we are referring to Power-to-Liquid. In the Power-to-Power path, the hydrogen is then stored for future use and transformed (from its stored state) back into power through the use of a fuel cell.
Initially the main application for this transformation technology has been the production of synthetic gaseous fuels. Blending the gas into the grid is compatible with existing infrastructures. The good news is that new projects are being announced at a weekly rhythm, and the liquid fuel production, which has been severely under-represented in the number of developing projects, is starting to increase.
If we take a look at the spread of projects, 1/3 of them focus con the transformation of hydrogen into gases, liquid fuels or chemicals. When CO2 needs to be introduced in the equation (following the methanation process for converting CO2 to a useful product), the main source in these new projects, is biogas or biomass plants, few of them obtain the CO2 from industries nearby.
What I find the most exiting of these technologies is the potential they have to contribute to sector-coupling by transferring renewable electricity into a number of other processes. Firstly, shifting it into chemical energy of synthetic energy carriers, secondly, transforming it into heat used for high temperature processes and thirdly by creating circular economies where the exhaust of an industry is used as feedstock into another one or into a different processes.
Momentum is building up, although Power-to-X solutions seem secondary technologies that could bring a benefit when certain requirements, like the availability of enough renewable energy, are in place. I argue that the latest law enforcements on hydrogen usage are going to give a push to such developments, lifting the industrial applications developments and increasing their share of the pie in the near future.
