Solar Concentrators Shown to Generate 1,050°C Industrial Heat

Again we have welcome incremental improvement and enough to provide usable heat flux. Hard to take seriously until we operate a smelter.

what is true is that our engineers are now learning to manage heat far better, because it has gotten easier.

Few Reverse Rankin Cycle engines though converting spent steam water down to room temperature while taking off electricity.

Solar Concentrators Shown to Generate 1,050°C Industrial Heat

November 18, 2024 by Brian Wang

https://www.nextbigfuture.com/2024/11/solar-concentrators-shown-to-generate-1050c-industrial-heat.html#more-199071

New experiments by swiss researchers have show that industrial-relevant temperatures of 1,050°C can be generated from solar concentrators. Solar power for industrial heat would be able to decarbonize power as much as converting electricity generation to stop using fossil fuel.

Current solar converters are expensive and inefficient when generating temperatures above 1,000°C for industrial processes. 

Researchers now show a thermal trap effect, triggerable by exposing common semi-transparent materials (e.g., quartz and water) to solar radiation, can increase the viability of solar receivers by suppressing radiative losses at high temperature.

A validated numerical model is applied to show how receivers exploiting thermal trapping achieve targeted temperatures at lower solar concentrations, i.e., cost, with the same thermal efficiency of state-of-the-art solutions or at higher efficiency for equal concentration.

Glass, steel, cement, and ceramics are at the very heart of modern civilization, essential for building everything from car engines to skyscrapers. However, manufacturing these materials demands temperatures over 1,000°C and relies heavily on burning fossil fuels for heat. These industries account for about 25% of global energy consumption.

Semitransparent materials such as quartz can trap sunlight — a phenomenon called the thermal-trap effect. The team crafted a thermal-trapping device by attaching a synthetic quartz rod to an opaque silicon disk as an energy absorber. When they exposed the device to an energy flux equivalent to the light coming from 136 suns, the absorber plate reached 1,050°C (1,922°F), whereas the other end of the quartz rod remained at 600°C (1,112°F).

Previous research could not produce more than demonstrate more than 170°C (338°F) using the thermal-trap effect.

Simulation models show that thermal trapping achieves the target temperature at lower concentrations with the same performance, or at higher thermal efficiency for equal concentration. For example, a state-of-the-art (unshielded) receiver has an efficiency of 40% at 1,200°C, with a concentration of 500 suns. The receiver shielded with 300 mm of quartz achieves 70% efficiency at the same temperature and concentration. The unshielded receiver requires at least 1,000 suns of concentration for comparable performance.

Casati and his colleagues are now optimizing the thermal-trapping effect and investigating new applications for the method. So far, their research has been promising. By exploring other materials, such as different fluids and gases, they were able to reach even higher temperatures. The team also noted that these semitransparent materials’ ability to absorb light or radiation is not limited to solar radiation.