German research team develops high-performance heat pump to convert waste heat from paper mills into industrial steam

Engineers have recently unveiled a powerful 1.2 megawatt (MW) heat pump capable of converting waste heat from the paper production process into industrial steam at approximately 248 degrees Fahrenheit (120 degrees Celsius). This heat pump was manufactured by a research team from the Fraunhofer Institute for Energy Infrastructure and Geothermal Energy (Fraunhofer IEG) and tested at the Felix Schoeller GmbH & Co. KG paper mill located in Hesse. The trial was conducted under the EU-funded PUSH2HEAT project.

The system utilizes heat that would otherwise be wasted to produce steam required for industrial processes. According to the institute, the system can reduce carbon dioxide (CO2) emissions by up to 600 tons annually and help decrease reliance on natural gas. Project manager Reuven Paitazoglou stated, "Industrial enterprises need solutions that combine climate protection, energy supply security, and competitiveness. High-temperature heat pumps make it economically feasible to utilize previously unused energy sources."

How the Heat Pump Works

From waste heat to steam, industrial processes typically operate steam systems at high pressures exceeding 212 degrees Fahrenheit (100 degrees Celsius). In most cases, producing this steam requires the combustion of fossil fuels, particularly natural gas. On the other hand, the burning of fossil fuels releases carbon dioxide and other greenhouse gases, contributing to climate change and air pollution. To address this challenge, the team developed a two-stage heat pump capable of upgrading low-temperature waste heat into usable industrial steam. The system captures excess heat from paper production, with temperatures ranging from 86 to 158 degrees Fahrenheit (30 to 70 degrees Celsius), and then raises it to approximately 248 degrees Fahrenheit.

During approximately 300 hours of operation in 2026, the pump achieved an average steam output of about 700 kilowatts (kW). At the same time, its steam production was around 1.2 tons per hour, with a pressure of about 2.3 bar. The performance factor reported by researchers was 2.30, meaning the useful heat provided by the system exceeds the electrical energy required to operate it by more than double. If the system operates for 4,000 to 5,000 hours, it could avoid up to 600 tons of carbon dioxide emissions annually, equivalent to a reduction of about 220 pounds (100 kilograms) of CO2 emissions per megawatt-hour (MWh) of heat compared to natural gas steam production.

Potential Applications of the Technology

This demonstration is part of the EU-funded PUSH2HEAT project, which explores ways to reuse industrial waste heat. While the project primarily focuses on paper and chemical production, this technology may also find applications in the pharmaceutical and food industries. Fraunhofer IEG coordinated the scientific aspects of the testing and proposed a monitoring system to assess its performance. The team examined how the pump could be integrated into existing production processes and steam networks. Paitazoglou emphasized the importance of expanding the application of this technology, stating in a press release, "The demonstration plant in Weisenborn lays an important foundation for the future use of this technology in other industrial applications."

Full-load testing is set to begin in September 2026, with the team planning to evaluate the system under real industrial conditions for one year, anticipating further improvements before the project concludes in 2027.

Future Prospects of High-Performance Heat Pump Technology

The development of this high-performance heat pump technology not only effectively reduces carbon dioxide emissions in industrial production but also decreases reliance on traditional fossil fuels, aligning with the current global demand for sustainable development. As the impacts of climate change intensify, the industrial sector urgently needs to seek alternative energy solutions. The successful application of this technology is not limited to the paper and chemical industries but may also play a significant role in other fields such as pharmaceuticals and food, further advancing the green transformation of industry.