From Research to a Megawatt Prototype
TPSÂ | WERNER WIGGEN, Managing Director
From Research to a Megawatt Prototype
Inductively Coupled Plasma as a Key Technology for Electric Process Heat
Decarbonizing energy-intensive industrial processes is one of the greatest challenges of the coming years. The aluminum industry in particular faces the task of replacing fossil fuels such as natural gas with climate-friendly alternatives without compromising product quality, economic viability, or facility availability. One promising solution is the use of plasma as an electric heat source. To this end, TPS is developing a new technology capable of completely replacing conventional natural gas burners. This is achieved through inductively coupled plasma burners specifically designed for industrial high-temperature processes.
PLASMA AS THE HEAT SOURCE OF THE FUTURE
Plasma is often referred to as the fourth state of matter. When sufficient energy is supplied to a gas, electrons are released from their atomic bonds. This creates an electrically conductive medium consisting of ions, electrons, and neutral particles. Natural examples of plasma include lightning and the sun.
For thermal industrial processes, plasma offers significant advantages. Since energy is coupled directly through electricity, heat can be generated entirely free of CO2 emissions, provided that electricity from renewable sources is used. At the same time, the technology allows precise control of the process atmosphere through the selection of suitable process gases. In addition, its compact design enables comparatively simple integration into existing furnace systems and significantly reduces the effort required for retrofitting.
In principle, various plasma technologies exist. While arc plasmas are already available at high power levels, electrode wear results in increased maintenance requirements. Microwave plasmas are primarily suitable for lower power levels below approximately 100 kW. For industrial applications in the megawatt range, inductively coupled plasma technology offers the greatest potential in terms of efficiency, operating costs, and maintenance requirements.
SYSTEMATIC DEVELOPMENT OVER SEVERAL YEARS
Development work led by TPS began with feasibility studies at the University of Mining and Technology in Freiberg, Germany. Initial tests confirmed that aluminum can, in principle, be melted using plasma. At the same time, positive metallurgical effects were observed, including low oxide formation and low hydrogen pickup in the metal.
In parallel, TPS investigated various plasma concepts for industrial furnace systems at the Institute of Technology in Karlsruhe, Germany. The analyses showed that inductively coupled plasmas offer significantly greater economic potential at high power levels than alternative plasma technologies.
Over the following years, the work focused on optimizing plasma parameters, power electronics, and burner geometry. Numerous simulations and experimental trials resulted in continuous efficiency improvements and enabled operation with various process gases, including nitrogen, air, oxygen, and carbon dioxide.
An important milestone was reached in May 2025. For the first time, an aluminum melting furnace was operated exclusively with a TPS plasma burner. During this trial, 100 kg of aluminum was completely melted using plasma. The results showed very low dross formation as well as promising metallurgical properties of the molten metal.
THE STEP INTO THE MEGAWATT RANGE
Following successful validation at pilot scale, the current focus is on scaling the technology for industrial applications. At the Ranshofen site, a research and development system with a power rating of one megawatt is currently in operation. This system forms the basis for the transition from the development phase to industrial deployment.
The installation is based on newly developed modular power electronics with an output of 1 MW per module, enabling the operation of an inductively coupled plasma burner in the power range relevant for industrial applications.
Particularly noteworthy are the expected efficiency levels. While previous solutions were often limited by high losses in the power electronics, the TPS concept achieves a burner efficiency of approximately 88 to 89 percent. This includes all conversion losses in both the burner and the power electronics. As a result, the technology reaches an efficiency range that enables the economically viable electrification of energy-intensive high-temperature processes. Another advantage lies in the extremely high plasma temperatures of well above 10,000 °C. This allows heat to be transferred with comparatively low process gas flow rates. Compared to conventional burner systems, this reduces exhaust gas losses and improves energy utilization within the furnace.
NEXT MILESTONE: INDUSTRIAL DEMONSTRATOR
The next development step this year is the integration of a 750 kW demonstrator into an aluminum melting furnace, where the system will be tested under near-production conditions. The objective is to validate the technology and collect data on energy consumption, process stability, melting performance, emissions, and metal quality.
The results achieved to date indicate that inductively coupled plasmas have the potential to make a significant contribution to the decarbonization of thermal industrial processes. With the current 1 MW prototype, TPS has reached a decisive stage of development and established the foundation for deploying this technology on an industrial scale.