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New tech melts steel and concrete using only solar energy

In a remarkable shift away from fossil fuels, researchers have developed a method with thermal mapping to achieve temperatures over 1,800°F (1,000 degrees Celsius) using solar energy — a significant leap toward clean energy solutions for heavy industries like steel and cement production.

Typically reliant on carbon-intensive fossil fuels, these sectors could see a transformation as this solar technology promises a sustainable alternative for high-temperature processes essential to modern civilization.

Pushing solar energy to new heights

The concept, which has been detailed in a recent study from a team in Switzerland, revolves around the use of synthetic quartz to trap solar energy effectively at extremely high temperatures.

This innovative approach utilizes a semitransparent quartz rod paired with an opaque silicon disk, which serves as the energy absorber.

When exposed to an intense light equivalent to that from 136 suns, the setup not only reached but maintained a remarkable temperature of 1,922°F (1,050°C) at the absorber plate, while the opposite end of the quartz rod remained significantly cooler at 1,112°F (600°C).

This striking temperature differential underscores the efficiency and potential of the thermal-trap effect in practical applications.

Potential game-changer

Emiliano Casati of ETH Zurich, the study’s corresponding author, explains that the significance of this technology extends beyond its impressive temperature achievements.

Previous attempts at harnessing solar thermal energy struggled with efficiency, particularly at temperatures necessary for industrial applications.

“Previous research has only managed to demonstrate the thermal-trap effect up to 170°C (338°F),” notes Casati. “Our research showed that solar thermal trapping works not just at low temperatures, but well above 1,000°C (1,800°F). This is crucial to show its potential for real-world industrial applications.”

Further simulations conducted by the team showcased that the thermal trapping could achieve these target temperatures at lower concentrations with the same performance, or at higher thermal efficiency for equal concentration.

For instance, a conventional unshielded receiver, which typically has an efficiency of 40% at 2,192°F (1,200°C) with a concentration of 500 suns, is markedly outperformed by the receiver shielded with 300 mm of quartz, which achieves a 70% efficiency at the same conditions.

Solar energy tech and sustainability

With the foundational research now laid, Casati and his team are focusing on refining this technology and exploring new applications.

Their ongoing experiments with different materials, such as various fluids and gases, have already demonstrated the ability to reach even higher temperatures.

This versatility highlights the potential of semitransparent materials in absorbing not just solar radiation but possibly other forms of light and radiation as well.

Getting governments and the public onboard

Raising public awareness and educating industry stakeholders about solar thermal energy technology is crucial for its widespread adoption. Educational initiatives play a significant role in this effort.

Programs designed to inform the public about the benefits of solar thermal technology can help demystify the science and highlight its potential to reduce carbon emissions and enhance energy efficiency.

Workshops, seminars, and online courses are effective ways to spread knowledge about how solar thermal systems work and their environmental and economic advantages.

Community programs also contribute to promoting sustainable energy solutions. These programs can include local solar power projects, where communities come together to install and maintain solar thermal systems.

Such initiatives not only provide clean energy but also foster a sense of collective responsibility and empowerment. They can include demonstrations, hands-on workshops, and informational sessions that illustrate the practical applications of solar thermal technology.

Harnessing the power of the Sun for a greener tomorrow

“Energy issue is a cornerstone to the survival of our society,” Casati asserts. “Solar energy is readily available, and the technology is already here. To really motivate industry adoption, we need to demonstrate the economic viability and advantages of this technology at scale.”

By harnessing the power of the sun and minimizing heat loss, this innovative technology paves the way for a more sustainable future.

As researchers continue to optimize the process for large-scale implementation, the potential for solar energy to replace fossil fuels in challenging industrial applications grows ever closer.

This breakthrough serves as a reminder that, with ingenuity and dedication, we can find solutions to even the most daunting challenges posed by climate change and create a cleaner, greener world for generations to come.

The full study was published in the journal Device.


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