By Helga Baumfalk
From February 2022 onwards, Therese Mölk will be using green hydrogen (H2) for the first time, for thermal utilization, and for baking bread. By doing this, the bakery subsidiary of the Austrian food retailer MPREIS is probably breaking new ground worldwide.
Therese Mölk’s aim is nothing less than decarbonizing bread production. Ewald Perwög, who heads the Sustainable Energy Solutions business area of MPREIS and who has decisively advanced the hydrogen initiative on which the company has been working for six years, says, “We want to make our baked goods without burning fossil energy sources, thus not only showing that this is possible but also making a significant contribution to climate protection.”
The foundation stone for the project’s ‘centerpiece’ – the electrolysis plant designed to supply green hydrogen – was laid in March 2021. Building work is now complete. According to Perwög: “We are now in the commissioning phase. We plan to start generating hydrogen in February 2022. Immediately after that, hydrogen will be used for the first time for thermal purposes and for baking. The H2 refueling station for our logistics fleet is currently being built and is scheduled to start operation in calendar week 14/22. The first three logistics trucks with hydrogen-fuel-cell drives will then begin operating.”
Ground-breaking ceremony for the hydrogen plant with (left to right) Ernst Fleischhacker (Green Energy Center), Peter Paul Mölk and Julia Mölk (MPREIS), Deputy State Governor Josef Geisler, Stefanie Graber (Therese Mölk Bakery), Erich Ruetz (Mayor of Völs), and far right Ewald Perwög (MPREIS Sustainable Energy Solutions)
When the plant is running, Therese Mölk’s eight ovens will be supplied with thermal energy via a heat-transfer oil system. The project manager says: “When we convert hydrogen into thermal energy in our H2 burners, all the ovens that need heat will be supplied with CO2-free heat from green hydrogen.” He goes on to explain: “In our project, hydrogen is converted into thermal energy using an innovative dual-fuel burner that burns H2 and natural gas, and can switch between these media while it is working. We operate several burners/boilers. The new combined burner/boiler in our coupled system is intended to ‘take the lead’ and is not supplied by our oven builder. Integrating the control technology into the existing cascaded burner/boiler operational management will be implemented together with our oven builder. Therefore, the necessary consultations with the latter here relate only to adaptation work to integrate our innovative dual-fuel burner into our combined boiler/burner (in which energy is supplied to the heat-transfer oil).”
The Therese Mölk bakery
The Therese Mölk bakery is a production unit newly built for the MPREIS company in 2013. Bread is baked without additives according to the philosophy: “Nature. Craftwork. Time. Nothing else.” The bakery prepares around 12,000 tonnes of bread and baked goods per year, which is supplied to MPREIS supermarkets and specialist outlets under the “Baguette” brand in Austria and the Italian South Tyrol. Sustainability is the company’s fundamental principle. State-of-the-art technologies enable a 40% energy saving, it operates its own combined heat-and-power plant, and a photovoltaic installation captures more than 800,000 kWh/year of solar energy. More information at: www.therese-moelk.at
No adaptations to the existing premises were needed. Perwög says: “Fortunately, our boiler-house was built with an extension area for a third heat-transfer oil heater. We are now using this free space. There was no need for adaptations on the ovens as a result of using hydrogen. The gas warning installation (CH4) that was present in our boiler-
house, in any case, is being enlarged and equipped with an H2 sensor system. H2 is supplied to the burners at a maximum pressure of 5 bar, so there is also no need for changes in the Ex-protection concept of our operating plant.”
As mentioned, the burner is a novel design. For Therese Mölk, it was important to be able to operate the baking process independently of the presence of hydrogen. As Perwög reports: “That was why we wanted a new combined burner/boiler that can also burn natural gas. It is impossible for us to retrofit our existing boiler with an H2 burner because the physical properties of CH4 and H2 are too different in this respect.” He explains that CH4 and H2 differ with regard to flame velocity, energy content and viscosity, among other things.
Green hydrogen is intended to be used in parallel to both ‘refuel’ heavy goods vehicles (HGVs) and to fire ovens. The two uses go hand-in-hand. He says that heating will be the first step, and the HGV refueling station is intended to follow shortly thereafter. Perwög also has policy expectations: “In fact, green hydrogen is ‘green’ because it is obtained from regenerative electricity by using a CO2-free production process (electrolysis). Now, even though natural gas prices have undergone an unparalleled price increase in recent weeks, electricity is still a considerably more expensive energy source. Currently, therefore, it is not yet possible to replace natural gas with electricity for economic management reasons. To achieve decarbonizing in this area as well, we need rules that make the emission of CO2 from natural gas so much more costly that green hydrogen produced using renewable electricity can compete on price.”
Regarding prices, MPREIS has also found a solution: “We utilize the fact that we market our electrolysis plant on what is called the ‘controlled energy market’ and take so-called ‘surplus’ electricity there from the grid. From the cost price point of view, this electricity is considerably cheaper than the electricity we purchase on a regular basis. Hydrogen generated by using this electricity can even compete with natural gas in terms of cost, and it can then be used to bake CO2-neutral bread.”
For MPREIS, the goals are clear. Perwög reiterates: “As a company, we are keen to reduce our CO2 footprint and to bring it to zero. That’s why, for us, generating industrial process heat is just as important as finding substitutes for diesel as an HGV fuel. In our view, there is no such thing as green CO2. Emission of CO2 must be avoided if we want to achieve the Paris climate goals.”
The MPREIS hydrogen initiative
MPREIS is a trailblazer. Nothing comparable existed, so the food retailer took it into its own hands to create a hydrogen initiative with the aim of reducing its CO2 footprint to zero in the long term. They brought FEN Systems onboard for strategy and project development, the TIWAG/TINETZ electricity network for electricity purchase, and ILF for technical implementation – all from Austria. The electrolysis technology originates from Switzerland (the IHT company).
The plant, which will come into operation on an area of around 1,000m2 close to the Therese Mölk bakery, is run by PAE electrolysis (pressurized alkaline electrolyzer). It is 9m high and designed to produce green hydrogen from green electricity (from hydroelectric power). The project’s investment volume is around EUR 13 million and is being supported by the European Commission, the Austrian federal government and the Swiss Confederation.
MPREIS plans to use the green hydrogen for process heat to supply Therese Mölk’s ovens with CO2-free heat, and for transport mobility. The initial intention is for three H2-fuelled HGVs to begin using hydrogen, and the whole fleet will be gradually converted to H2 vehicles. With the hydrogen initiative, MPREIS has its sights on a new business case. In the final expansion stage, the electrolysis plant will be able to supply twice as much H2 as the company needs.
