In the future solar energy could be used to produce cement or steel, instead of burning coal or oil for this purpose. Researchers at ETH Zurich have developed a thermal trap that can absorb concentrated sunlight and deliver heat at over a thousand degrees
Large-scale solar concentrating technologies are already established at an industrial scale for solar power generation, for example in Spain, the US, and in China. These plants typically operate at up to 600 degrees. At higher temperatures, heat loss by radiation increases and reduces the efficiency of the plants. A major advantage of the thermal trap developed by ETH Zurich researchers is that it minimizes radiative heat losses.
High-Temperature Solar Plants
Our approach significantly improves the efficiency of solar absorption,” says Casati. “We are, therefore, confident that this technology supports the deployment of high-temperature solar plants.” However, detailed technical and economic analyses are still pending, he says. Such analysis is beyond the scope of the current experimental study, which the researchers have published in the scientific journal Device.
Casati is continuing his research to optimize the process. The technology could one day make it possible to use solar energy not only to generate electricity, but also to decarbonize energy-intensive industries on a large scale. “To combat climate change, we need to decarbonize energy in general,” says Casati. “People often think of energy in terms of electricity, but we actually use about half of our energy in the form of heat.”
For more on this research, see Solar Power Shatters the 1,000°C Barrier for Industrial Heating.
Reference: “Solar thermal trapping at 1,000°C and above” by Emiliano Casati, Leo Allgoewer and Aldo Steinfeld, 15 May 2024, Device.
DOI: 10.1016/j.device.2024.100399