Storing the sun’s heat at 1,200°C

Closing the CO₂ cycle by changing climate-damaging carbon dioxide again into kerosene, gasoline and diesel: That’s the concept behind Synhelion. The ETH spin-off makes use of the warmth of the solar to supply artificial fuels (Synfuels) from CO₂ and water.

In June 2024, within the German metropolis of Jülich, Synhelion inaugurated DAWN: the world’s first industrial plant for the manufacturing of photo voltaic fuels. Due to a collaboration with the Empa Laboratory for Excessive-Efficiency Ceramics, DAWN can produce renewable fuels across the clock, even at night time.

To show CO₂ and water again into fuels, DAWN wants one factor above all—vitality. A big mirror area focuses the daylight onto a single level on the photo voltaic receiver. The steam inside reaches a temperature of as much as 1,200°C because of the concentrated vitality of the solar.

This high-temperature course of warmth is used to function the reactor, whereas the excess is fed into the thermal energy storagewhich is a chamber a number of cubic meters in dimension, crammed with very particular bricks. These bricks—a joint growth by Empa and Synhelion—function non permanent storage for the big warmth. In a single day, it’s this warmth reservoir that provides the reactor with vitality and retains it operating.

Needed: The ‘super-brick’

At 1,200°C, although, not all bricks are created equal. In direct contact with the ultra-high temperature steam, even ceramics corrode. Not one of the refractory bricks out there available on the market have been designed for these extreme conditionsso Synhelion approached Empa.

“The research group led by Empa researcher Gurdial Blugan is one of the few to study the corrosion behavior of ceramics at such high temperatures,” says Lukas Geissbühler, Head Thermal Programs at Synhelion.

In a two-year undertaking, Blugan and Empa scientist Sena Yüzbasi, along with Synhelion, got down to discover a appropriate ceramic. Corrosion resistance was just one side. The fabric additionally needed to have a excessive warmth capability, be mechanically sturdy and stand up to thermal shocks that may happen when the system is powered down. It additionally needed to be cheap to supply, as a result of the plant in Jülich is only the start for Synhelion.

The researchers designed their very own high-temperature tube furnace along with the Empa workshop and Synhelion. In it, they uncovered totally different ceramic samples to the corrosive steam environment—for as much as 500 hours.

“It got pretty hot in our lab during these experiments,” says Blugan. However the sweating was price it: The researchers have been capable of finding a cloth that might stand up to the intense circumstances.

Along with their undertaking companions, they refined the fabric composition and optimized the manufacturing process as a way to additional enhance the material properties and cut back prices. The bricks have been then produced by a associate firm in Germany and put in in Jülich.

“As a researcher, it’s not often that you get to see your research applied on such a scale, it is quite a unique experience,” says Yüzbasi. The scientist, who now works within the vitality business herself, is especially happy that her work is getting used within the renewable vitality sector for local weather safety.

Forging on collectively

“Empa has made a valuable contribution to the development of our thermal storage unit and was able to respond to Synhelion’s specific requirements thanks to its flexibility,” says Lukas Geissbühler. Whereas DAWN goes into operation, Synhelion and Empa are already planning their subsequent joint undertaking.

For future vegetation, they need to additional develop the fabric and make it much more sturdy. Synhelion’s second plant for the manufacturing of photo voltaic gas is to be inbuilt Spain from 2025. The objective: even bigger warmth storage items, even larger temperatures. For the reason that larger the temperature, the extra environment friendly the gas manufacturing.