Hydrogen and electricity from wind and sun are partners in the energy transition
Guest article Prof. Dr. Birgit Scheppat
What will mobility look like in the future, how will products be produced and what are the prerequisites for the functioning of this new hydrogen economy including "All Electric"?
With Fit for 55, the Renewable Energy Directive (RED II), the Clean Vehicle Directive and other programmes, European legislation has made it clear that the target of limiting global warming to 1.5 °C can only be achieved by Europe if it the full range of measures to avoid CO2 are implemented. The transition from fossil fuels to an electricity-driven industrial society is pivotal. Various paths have been marked out, but there is certainty surrounding one particular outcome: hydrogen will be an important energy vector of the future. And, yes, that will cost a great deal of money, but it will also open up many and multifaceted new opportunities in the various application areas.
Whether everything is run with electricity or with hydrogen and fuel cells, the starting point is the same, namely electricity from renewable energy. Three things are needed to ensure that the electricity from these energy sources can be used: energy production, transport and storage. The generation of green electricity from wind and sun has been technically clarified and can always be improved. All the necessary prerequisites for long-term use of the systems and their market maturity have been fulfilled. Claims regarding transport and storage, on the other hand, no longer garner such an unequivocal response. In particular, the storage or provision of energy as "electron (battery) or molecule (hydrogen)" continues to be controversial and “contested”.
1 kg of hydrogen produced using electrical energy from photovoltaics and the sun contains 33.3 kWh of energy – this corresponds to approx. 2.75 l of petrol. One kilogramme of the best lithium-ion batteries stores up to 500 Wh, i. e. the same amount of energy can be stored in one kilogram of hydrogen as in a 66 kg lithium-ion battery. This highlights the potential of storing energy using hydrogen. Today, the efficiency of hydrogen production by electrolysis still stands at around 70 percent. However, this can be increased if the hydrogen is used in addition to the oxygen (in areas such as waste water treatment) and the waste heat. Here we can achieve efficiency levels of almost 90 percent.
The technologies – batteries as well as fuel cells/hydrogen – have essentially been developed. The issues that need to be resolved, especially for the production of hydrogen, are how quickly series production for electrolysis systems can be set up and how distribution of hydrogen can be enabled at a reasonable cost, preferably by pipeline, etc. Power generation from photovoltaics and wind needs to be facilitated and expanded, and the market needs to be ramped up in order to get the figures up – and thus the prices for installed capacity down.
Hydrogen is a substance that is used extensively in many technical and chemical processes. In the chemical industry, it is harnessed to produce paints, plastics, greases and fertilisers – but with hydrogen from natural gas. This hydrogen was previously unbeatably cheap because natural gas was cheap and the carbon dioxide generated during reforming was released into the environment. In addition, large amounts of hydrogen will be needed in the future in the steel and cement industries. Replacing the hydrogen here is solely a question of costs. In other words, it will take many large producers of renewable energy plus pipelines to keep costs down. The use of so-called green hydrogen depends on whether the necessary wind and photovoltaic systems can be set up quickly and at a reasonable cost. The hydrogen economy is not something new. Germany’s municipal utility companies (Stadtwerke) used to produce city gas that already contained < 50 percent hydrogen. When it comes to handling hydrogen in low-pressure conditions of up to 300 bar, all the technical questions have been more or less clarified. As soon as the standard for hydrogen has been defined, hydrogen will be used silently – as has been the case up to now – in the various applications. The only issue that remains genuinely critical is how quickly the costs of the generators, storage and infrastructure can be reduced and how quickly they can be installed or expanded.
The use of hydrogen is a great opportunity to determine whether there are any starting points for these new technologies in the company's own portfolio. Metal/plastic composites, stamping/pressing, surface coating, seals, smart solutions, etc. – in many of the fields mentioned above, there has only been preproduction operations to date and low-cost, reliable pumps, turbochargers, sensors, etc. are all missing from the equation. The situation could actually be described as an Eldorado of new opportunities.
The prerequisite for all of this, however, is engaging and working with the technologies. They will come, sooner or later. Today's processes in industry, buildings and transport will be transformed – the European legislation currently being implemented is already paving the way for this: RED II, Fit for 55, etc. The fields of technology need to be approached with curiosity and developments need to be initiated. It will require a lot of new, good, inexpensive and sustainable ideas – and now is the time to start and pick up speed.
Prof. Dr. Birgit Scheppat, since June 2006 Professor for Hydrogen and Fuel Cell Technology at the RhineMain University of Applied Sciences. In addition, she is active in various committees, such as the German Physical Society, Energy Division and the VDI. She is also a board member of the Hydrogen and Fuel Cell Initiative Hessen and a member of the DWV presidium.