Hitachi Zosen Inova and the Association of Municipalities for Waste Disposal Region Aarau-Lenzburg will produce hydrogen at the waste incineration plant in Buchs (AG), Switzerland, in the future.
The main customer of the hydrogen produced is Messer Schweiz AG in Lenzburg. For HZI, it is the second innovative project in the canton of Aargau in a very short time; it was only in September that the delivery of a CO2liquefaction plant for a Swiss pioneering project in Nesselnbach.
As part of the energy transition towards renewable energies, green hydrogen is being used as an energy carrier with high density and low CO2footprint. The cost-effective availability of green hydrogen is the key to the success of the energy transition. This can be achieved in cities with low-cost surplus electricity from renewable energies.
Due to its proximity to the place of consumption, it is available without complex logistics. Since thermal waste treatment plants are recycling plants, the use of the electricity generated to produce hydrogen is a further step towards improving the contribution of such plants to the circular economy. Hydrogen production can be either base-load capable or fluctuating.
This flexibility allows the availability of other renewable power generation plants to be taken into account in the best possible way, so that more hydrogen is produced at high wind and solar productivity and vice versa.
Because hydrogen can be stored without losses, this chemical storage proves to be more effective and scalable than battery storage.
A joint project has now been launched together with the Association of Municipalities for Waste Disposal Region Aarau-Lenzburg (GEKAL), in which the Swiss-Japanese cleantech company Hitachi Zosen Inova (HZI) has developed its first waste-to-hydrogen (WtH)2) plant on a commercial scale.
HZI will take over all planning and construction work for the plant on the GEKAL site and will also be the owner and operator in the first few years. The hydrogen produced is used as a technical gas for industry and mobility applications, for example as an environmentally friendly fuel for public transport and private vehicles.
HZI produces hydrogen and oxygen using electricity from the Buchs waste incineration plant (KVA) and pure water. The oxygen is released into the environment, the hydrogen is compressed and stored in special tanks. For this purpose, HZI uses an alkaline electrolyser that uses 550 Nm3/h green hydrogen at 350 bar.
This corresponds to the quality standard for hydrogen for mobility purposes according to SAE 2719 and ISO 14687. The power-to-gas plant also includes a filling station. The plan is to produce around 200 tons of hydrogen per year, which corresponds to about 10 to 15 gigawatt hours of electricity.
This is enough for a hydrogen-powered car to travel around 20 million kilometres or for up to 1000 fuel cell vehicles to be refuelled per year. Messer Schweiz AG, based in Lenzburg, which has concluded a contract for the purchase of the hydrogen produced, specialises in the supply of industrial gases.
After commissioning, the new PtH2plant represent a valuable and above all local source of green hydrogen and reinforce the circular concept of the thermal recycling plant.
After construction, the hydrogen plant will be integrated as part of Swissgrid SRL services. This novel concept regulates demand and overproduction in the Swiss power grid. If a primary producer fails in the grid, secondary generators, such as KVA Buchs, contribute to the stabilization of the grid via electricity feed-in.
A so-called “negative grid balancing” is also possible if too much renewable electricity is produced compared to the plan. In this case, the hydrogen plant can take up to 2 MW from the grid. The producers of renewable energies (such as wind turbines) do not have to be shut down or only later.
A cost-efficient and environmentally friendly joint effort
The construction of the hydrogen plant offers many advantages in economic and ecological terms.
Christoph Wasser, GEKAL President says:
Hydrogen production allows us significantly greater flexibility if, for example, the demand for electricity is low.
“In this case, we do not feed electricity into the grid, but produce storable hydrogen.”
Fabio Dinale, Vice President Business Development at HZI, adds:
The use of the energy produced by KVA Buchs will be significantly improved by the hydrogen plant.
“By compensating to produce fossil fuels, we also reduce CO2-Balance sheet of the plant. In the future, other attractive technical solutions are also conceivable, such as the combination of hydrogen with CO separated from the exhaust gases of the KVA Buchs2. This enables a production cycle for methane.”
Dr. Hans Michael Kellner, CEO of the industrial gas specialist Messer Schweiz AG, adds:
For us as a buyer of hydrogen, the construction of the plant is an ideal opportunity to significantly increase the proportion of green hydrogen in our portfolio.
“Once the power-to-hydrogen plant is commissioned, locally produced green hydrogen will account for almost a third of our current local supply volume.”
Construction of the hydrogen plant at KVA Buchs is scheduled to start in June 2022, the first hydrogen production is scheduled to take place at the beginning of 2023 and full commissioning will take place a few months later, in spring 2023.