An energy revolution with green hydrogen
Projects like eFarm, companies like the HanseWerk Group and many other stakeholders in Germany's True North are betting on the enormous potential and overall systemic benefits of green hydrogen with regard to decarbonising our energy system.
If you want to experience the energy transitions at first hand, simply drive north from Husum towards Bredstedt and then stop at a large farm in Reußenköge. This spot - surrounded by marshes and seagulls, sunshine and solar panels, North Sea breezes and wind turbines, electrolysers and e-cars - is the headquarters of GP JOULE, a company working towards 100-per-cent use of renewables and their sustainable conversion into hydrogen, heat and mobility. The eFarm, the largest sustainable hydrogen mobility project in Germany to date, was initiated by GP JOULE and also began its success story here. This joint project is making hydrogen-based infrastructure a reality - from production and processing to its use in vehicles.
Melanie Koch studied energy and environmental management in Flensburg and started working on the state-funded eFarm project as a junior project manager in 2018: "At first there were only two of us, but we quickly grew and now have our own business unit - GP JOULE Hydrogen GmbH - with over 50 employees." Now, four years on, the 28-year-old from North Frisia is an authorised signatory for the eFarm and GP JOULE Hydrogen GmbH is implementing projects throughout Germany. In Melanie's view, this successful enterprise could only have got off the ground in Schleswig-Holstein and North Friesland: "We have incorporated many public wind and solar farms into our overall project. These project partners have now become co-shareholders in our company, efarming GmbH & Co. KG, which is another reason why everyone was behind this pilot project. They understood the urgency of making hydrogen marketable and integrating it into the ongoing energy transition. The authorities are also supportive of the overall concept - this is a clear advantage of our location, which wouldn't have been the case everywhere." Despite all their educational work, however, she says there is still an ongoing debate about using electricity directly rather than converting it to hydrogen on account of the reduced efficiency. "From a physics viewpoint, that statement is correct," explains Melanie. "In a battery, 70 to 80 per cent of the originally supplied kilowatt hour is still there at the end. In a fuel cell with zero waste-heat utilisation, this proportion is only 30 to 40 per cent." However, she believes this purely energy-based viewpoint is not expedient, and that it is important to analyse the energy system as a whole. "In the eFarm project, for example, we also factor in the use of waste heat in hydrogen production and optimally combine this with renewable heat networks. This brings the overall efficiency of electrolysis up to 95 per cent."
Another aspect is the grid-serving production of the fuel. "At times when we're generating a lot of wind and solar energy in the North, we can use this to produce hydrogen during these peaks, which we can then use at other times, for example for transport and in combined heat and power plants." According to Melanie Koch, it does not make economic sense to design the power grid purely around the peaks. In particular, she believes "peak shaving" is perfectly possible via hydrogen production. "Any discussion of efficiency then becomes moot, because otherwise the electricity would either not have been used at all, or its use would be prohibitively expensive due to the required expansion of the electricity grid. So it comes down to the system concept."
System efficiency is an important factor for GP JOULE. Melanie Koch believes mobility is a good example of this. "In heavy goods transport, batteries aren't efficient because they eat into a lot of the freight capacity and the lorry has to wait around for long periods at the charging stations. Also, a large logistics company wouldn't be able to charge one hundred trucks overnight because our electricity grid just isn't designed for that kind of connected load. The same applies to service stations and rest stops. An H2-powered truck, on the other hand, can be refueled using a CO2-free process in ten minutes with no loss of freight capacity."
As part of the eFarm project, GP JOULE Hydrogen has now established four hydrogen production plants and two hydrogen filling stations in North Friesland. "We drive from the production plants to the filling stations with mobile H2 trailers. These trailers remain at the filling stations until empty and are then exchanged - a kind of deposit bottle system for H2 storage."
The new electrolysers are being built in the immediate vicinity of the wind farms to remove the need for grid expansion and to faciliate the production of green hydrogen at low cost. The H2 can then be driven to various consumers within the local region, such as petrol stations and industrial facilities. The company is gradually rolling out this regional concept to other locations nationwide. The GP JOULE Group is thus making important contribution to the market ramp-up of green hydrogen, increasing security of supply and ensuring independence from external markets.