Electric and Hybrid Boiler Systems for Utilisation of Green Electricity

What role does the use of solar energy (photovoltaics) play in the sustainable generation of steam and hot water in Bosch boiler systems, and what advantages does this offer the food industry?

Daniel Gosse: Photovoltaics and, in general, electricity from renewable sources play an important role when it comes to climate-neutral process heat in the food industry. Photovoltaic systems generate green electricity from solar energy, which is then extremely efficiently converted into process heat in our electric steam generators. This enables energy-efficient, environmentally friendly processes that significantly reduce CO₂ emissions and support sustainable production targets. As solar energy is only available to a limited extent, hybrid solutions that enable a combination of green electricity and other energy sources are recommended. This way, food manufacturers benefit from the ecological advantages of green electricity without sacrificing the security of supply.

What challenges arise from the use of photovoltaics and other renewable energies in industrial heat generation?

Daniel Gosse: As already mentioned, one of the biggest challenges is the fluctuation in the availability of renewable energies, such as solar and wind power. According to studies by the Fraunhofer Institute, the sun in Germany provides on average only about 1,000 full-load hours of energy per year (there are 8,760 hours in a year), which means that solar power is not constantly available all year round. The use of hybrid boiler systems, which may consist of electric steam generators and conventional boilers or pure hybrid boilers with an integrated heating element, is an option here.

What are the advantages of hybrid solutions that combine electric heat generation and combustion?

Daniel Gosse: The advantage of hybrid solutions is that they combine flexibility, sustainability and security of supply. The operators of our hybrid boiler systems can prioritise green electricity and only resort to fossil fuels if the renewable electricity is insufficient. Our project with PepsiCo in Poland is a good example of this: The ELSB electrosteam boiler there primarily uses surplus green electricity from the on-site photovoltaic system. With an electrical output of 3.6 megawatts, the boiler can produce up to five tonnes of steam per hour. A natural gas-fired Bosch steam boiler is used for back-up and peak loads. This way, PepsiCo can benefit from a reliable supply while significantly reducing its use of fossil fuels.

How great is the potential for CO₂ savings through the use of renewable energies in heat generation?

Daniel Gosse: The efficiency of our electric steam boilers is up to 99.6%, which means that almost all the energy is converted into steam. If this electricity comes from renewable sources such as photovoltaics, the CO₂ emissions can be completely avoided. Companies that enter into long-term PPA (Power Purchase Agreements) for green electricity have the opportunity to make their processes completely climate-neutral. The CO₂ savings are considerable in the energy-intensive food industry, making green technologies an economically and environmentally advantageous solution compared to fossil fuels. However, the availability of renewable energy 365 days a year and, for example, the regional grid infrastructure for electrification are currently bottlenecks in many places.

What is the current market penetration of sustainable boiler systems in the food industry and what potential do you see for the future?

Daniel Gosse: In Germany, many industrial boiler systems are not yet state of the art. Studies by the German Heating Manufacturers Association (BDH) show that around 70 to 80 % of existing systems are outdated and that efficient technologies, for example for waste heat utilisation, are rarely used. In this context, increasing efficiency is the key to operating boiler systems more sustainably. We see great potential in food processing in particular, as heat sinks for utilising waste heat are available here at the same time. The retrofitting of efficiency modules such as exhaust gas heat exchangers is one of many measures that can be taken to exploit this potential and reduce fuel consumption while also reducing CO2 emissions.

What role do political conditions and funding programmes play in the expansion of CO2-neutral boiler systems?

Daniel Gosse:Funding programmes and political support are crucial to accelerating the transition to CO₂-neutral systems. In Germany, the Federal Ministry for Economic Affairs and Energy is currently funding decarbonisation projects with grants of up to 50 % for small and 40 % for larger companies, with a minimum investment of €500,000 for small companies and €1 million for larger ones (as at: August 2024). Subsidies like these make investing in green technologies more attractive to many companies. However, one hurdle remains: In Germany, the price of electricity and, in particular, grid usage fees are usually significantly higher than the price of fossil fuels (e.g. natural gas). In countries with smaller price differences, companies are therefore quicker to adopt sustainable technologies. The spread of electricity-based and other renewable solutions in Germany and Europe could be further promoted with more targeted funding and investment in the grid infrastructure.

Contact with the interview partner:
Daniel Gosse
E-Mail: daniel.gosse@de.bosch.com
Global Head of Marketing bei
Bosch Industriekessel GmbH
Nürnberger Str. 73
D-91710 Gunzenhausen
Germany