• Who is EMITEC within the solar thermal world?
Emitec was founded in 1986 and is a series supplier of metal catalytic converters and filters as an original equipment manufacturer for the automotive industry, agricultural machinery, stationary systems and industrial applications. Thanks to our many years of experience in the field of exhaust gas aftertreatment and the associated development of high-temperature-resistant materials, production technologies and thermomechanically robust designs, our expertise was first applied to solar thermal power plants in 2002. As part of two projects funded by the German Federal Ministry for Economic Affairs and Energy, in cooperation with the German Aerospace Center, a metallic solar absorber with optimized thermal efficiency compared to a conventional ceramic absorber for open volumetric power plants with air receiver technology was developed and tested under real conditions. Our robust EmiRec® solar absorber is therefore ideally suited for use in solar thermal power plants with CSP technology.
• What products or innovations and technological developments are EMITEC undertaking to improve the efficiency and competitiveness of solar thermal plants?
The metallic solar absorber has been proven in several test series to have a 7% higher thermal efficiency than a conventional ceramic absorber at an exemplary air outlet temperature of 650°C, which, in addition to more efficient system utilization, also has a direct effect on reducing the overall costs of a CSP system without having to accept any loss of performance. Due to the higher efficiency, fewer heliostats are required, among other things, which reduces a cost-driving factor while at the same time reducing the size of the plant.
Due to the higher thermal efficiency, a system with air receiver technology is now at a comparable efficiency level to a system with molten salt technology.
At Emitec Technologies, we are continuously developing and optimizing our production technologies and options while maintaining consistently high component quality and function in order to further reduce component costs for medium to large production runs in the future.
• Are there any current or future products that EMITEC is particularly excited about and that will contribute to the future development of solar thermal technology?
With the development of the metallic solar absorber EmiRec®, a major step has already been taken in air receiver technology by increasing the thermal efficiency. One of the advantages of air receiver technology is the simple handling of air as a medium and the wide range of possible applications, such as the operation of a steam turbine to generate electricity or direct use as process heat in manufacturing companies.
The trend shows that CSP plants are growing worldwide and have many possible applications. In addition to pure electricity generation, plants for the production of e-fuel by means of electrolysis of hydrogen and the combination of CO2 from the atmosphere are also possible and an important part of replacing fossil fuels in the future and thus contributing to global climate protection and decarbonization.
As an innovative and technologically open company, we would like to continue to participate in new projects and developments in the field of renewable energies in the future and contribute to achieving the climate targets that have been set.
• According to your knowledge and experience, what challenges does the sector face?
The renewable energy sector in particular forms a large field of different technologies in the area of solar solutions with their advantages and disadvantages. In addition to the well-known PV systems, CSP systems with molten salt and air receiver technology, wind power and hydropower/tidal power plants are available as energy suppliers and can be used individually depending on the surrounding conditions and topography.
We see a particular challenge in the variety and complexity of the different types of plant and possibilities for using and optimising renewable energies. This requires a wide range of expertise in the individual areas such as component design and production, control and regulation technology, plant planning, construction and commissioning of a power plant.
• How can EMITEC contribute to overcoming these challenges?
Emitec can draw on decades of experience, development and production using a wide range of technologies and expertise as the market leader for metallic catalytic converters in exhaust gas aftertreatment with over 370 million parts sold. In addition to prototype and series production, we have a large test center with hot gas test benches and our own simulation and development department, which enables us to react quickly to new trends and requirements and bring innovative products to the market.
As a supplier, we at Emitec want to enable plant manufacturers and ultimately plant operators to make ideal use of our metallic EmiRec® solar absorbers, individually adapted to the requirements and boundary conditions of their solar power plant and, as a result, to reduce the overall plant costs.
• How do you view the future of Solar Thermal sector?
Climate protection is becoming more and more important worldwide, and so is the issue of environmentally friendly and renewable energy generation. Solar energy plays a decisive role in this and is becoming increasingly important. The one «right», «best» or «most effective» way of using solar energy has not yet established itself, as there are different challenges, boundary conditions and requirements from application to application, as well as strongly fluctuating raw material prices, which have a decisive influence on the calculation of a power plant. Compared to the established extraction, processing and use of fossil raw materials for energy generation, there is still a lot of development potential in solar energy generation and use in order to become more efficient, protect the environment and reduce costs in the long term.
• Based on your professional experience, what research areas in new technologies and materials do you consider key to reducing costs in solar thermal technology?
Thanks to improved thermal efficiency, high component quality and a long service life, system and operating costs can be reduced, and efficiency increased.
From our experience, we can report on the metallic solar absorber which, due to its higher efficiency, offers enormous savings potential compared to the use of conventional ceramic absorbers in power plants with open air receiver technology. In cooperation with the German Aerospace Center, an absorber design was developed in several series of measurements on the degree of absorption and thermal efficiency as well as a CFD simulation, which ultimately achieved a thermal efficiency of 91% at an air outlet temperature of 650°C after extensive optimization measures. Subsequent tests on thermal shock resistance under real conditions on a solar test tower confirmed the robustness of the design.
Another key factor for the success of the solar sector is the minimization of production costs. Emitec can make a very positive contribution in this area with its EmiRec® product, which benefits from the high-performance mass production lines for metallic substrates for the automotive sector.
