New technology turns sunlight into heat to eliminate the use of coal in the aluminum industry
Who said that it is only in forests that there are projects to neutralize emissions of polluting gases (like the one supported by iFood in the Amazon)? In Saudi Arabia, deserts will also be part of efforts to remove carbon dioxide from the atmosphere and decarbonize the aluminum manufacturing process, which uses coal as an energy source.
Arabs are building greenhouses on the edge of the industrial city of Ras Al-Khair, in an area of seven square kilometers, informs Fast Company. It is an area equivalent to that of a thousand medium-sized official football fields, and work is expected to begin in 2024.
The aluminum produced in the region is used in the manufacture of cell phones, computers and cars. “Often these products have hidden embedded emissions that we are not aware of. That's a huge amount of CO2 that we are putting into the atmosphere”, Rod MacGregor, CEO and founder of GlassPoint, a company that plans to build the new system, based on solar energy.
The landscape that will be seen in the region, however, in no way resembles that of solar farms that we know. The technology that will be used to produce solar energy consists of large curved mirrors that hang inside the greenhouses and concentrate sunlight into pipes, heating the water inside so that it boils and produces steam.
“In this particular case, when end users need heat, it is much more efficient to go directly from sunlight to heat,” explains Rod. Most plants use coal to boil water and generate steam to refine bauxite, the mineral used in the first stage of aluminum manufacturing.
Reduction of carbon footprint
In partnership with the Saudi Arabian Mining Company, GlassPoint is planning a new 1,500 megawatt solar thermal installation at the company's refinery, which currently uses gas to produce steam. In this way, the company will be able to reduce its carbon footprint by half by switching to solar energy and will stop emitting 600,000 tons of CO2 per annum.
This new technology can also be used in other factories that use steam in their operations, such as the food industry, lithium producers and paper mills.
“As a category, industry is the largest consumer of energy in the world. And 75% of all the energy it uses is in the form of heat,” says Rod.
He explains that the technology for generating solar thermal energy is simpler and makes this option less expensive than alternatives such as green hydrogen. This type of energy generation, however, still costs more than using fossil fuels.
However, Rod believes that as refiners face new pressures – from brands, investors and new regulations such as a carbon tax on aluminum in the European Union – they plan to change. “In the beginning, we would go to an industrial complex and say, 'We can help you decarbonize,' and they would ask, 'Why do we want to do this?'” says Rod. “Nobody says that anymore.”
