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The spectre of global warming threatens life as we know it, but two young engineering students have not only come up with a concept that could help to solve the problem but have turned it into an economically viable commercial opportunity. They’ve founded a company called Climeworks. Let’s take a closer look at what they are trying to achieve and the practical benefits of their exciting new technology.

From Idea to Lab to Commercial Plant near Zurich

To reach global climate change reduction goals, 10 gigatons of CO₂ must be removed from the atmosphere every year. With a growing world population, especially in urban agglomerations, reaching that goal would be very difficult indeed. To date, not enough strides have been made to meet the well-known ‘two-degree’ objective, which by the way might lead to unprecedented consequences for cities. But now, we probably have new hope? In 2007, two students at the Swiss Federal Institute of Technology, Christoff Gebald and Jan Wurzbacher, came up with a revolutionary idea for a CO₂ collector that would take the greenhouse gas directly out of the air.

By 2009, they had presented their first working prototype, and they were ready to register their business and commercialize the concept. Later, they developed a modular format for their CO₂ plant, making it fully scalable and ready for bulk manufacturing. According to Climeworks’ founder, the industrial scale is able to filter about 900 CO₂ tonnes yearly. Recently commissioned in the Swiss municipality Hinwil close to Zurich, the new plant consists of a ten meters high steel construction equipped with 18 air soaking collectors plus control and process technology. It is located directly beside a waste incineration plant which provides the needed energy to run Climeworks’ plant.

Its Principle is Based on Using Derivatives of Ammonia

The carbon dioxide is filtered directly from the ambient air without any detours. On the roof top of the waste incineration plant, 18 filtering collectors have been installed. Fans suck in the ambient air, which is burdened with CO_2.

After absorption and desorption, the carbon dioxide reduced air will be released again. But what means absorption and desorption? The carbon dioxide is chemically absorbed on the cellulose-like filter’s surface which are equipped with amines, formally derivatives of ammonia. Aqueous ammonia can be used to capture carbon dioxide. However, this is absolutely nothing new. Saturation sets in after around three hours of continiously filtering the air passing through. Then, the fans are switched off and the closed internal space will be heated up to nearly 100°C by using the heat energy from the waste-to-energy plant. Little by little, the carbon dioxide dissolves from the amines – and the cycle starts all over.

What Will All That Carbon Dioxide be Used for?

Now that the large-scale version of the CO₂ collection plant is up and running and a production facility is churning out 150 collectors a year, sequestering 7,500 tons of CO₂ annually, you may be wondering what people will do with all that the greenhouse gas.

Of course, it could be stored underground, but the young entrepreneurs have other ideas too. The food and beverage industry needs CO₂, and CO₂ can be used as a means of generating renewable energy. However, it can also help us to increase our food production, and that is exactly what the first large version of the equipment is doing.

Growing Crop Yields by 20-30% with CO₂ Enrichment

At night, plants use CO₂ to build biomass. After all, carbon is the basis of all life on earth. The plants use the carbon and release the oxygen that forms part of the CO₂ molecule. For many years, growers have known that introducing extra CO₂ into greenhouses after dark will result in improved yields.

The commercial scale collector stands near a large range of production greenhouses, and the grower who operates them uses the CO₂ to enrich greenhouse air. He is boosting his harvest by 20-30% in the process. In this way, Climeworks’ CO₂ plant can impact on another issue that has troubled the world: food security.

Climeworks Sparks Global Interest

The European Commission is extremely interested in Climeworks’ world-first innovation, and corporate giants across a range of industries are taking note too. Audi was among the first to show an interest. It hopes to use CO₂ as a fuel. Naturally, the horticultural industry is extremely interested, and the food and beverage industry can use the CO₂ for carbonation processes.

Apart from these commercial uses for CO₂, the idea of slowing global warming by taking CO₂ from the atmosphere has generated widespread excitement.

Reducing Atmospheric CO2 by 1 Percent by 2025

Climeworks has set an ambitious goal to remove 1% of CO₂ from the atmosphere by 2025. CEO Christoff Gebald says that the goal is entirely reachable. Meanwhile, the company’s production facility is going all out to produce the CO₂ collectors that will realize this dream. Could one company save the planet? Perhaps not without the help and support of partners and clients, but Climeworks will make a significant difference as its unique collectors gain momentum on the market.

“Highly scalable negative emission technologies are crucial if we are to stay below the twodegree target of the international community,” says Christoph Gebald, co-founder and managing director of Climeworks. “The DAC-technology provides distinct advantages to achieve this aim and is perfectly suitable to be combined with underground storage. We’re working hard to reach the goal of filtering one per cent of global CO2 emissions by 2025. To achieve this, we estimate around 250,000 DAC-plants like the one in Hinwil are necessary.”

“With the energy and economic data from the plant we can make reliable calculations for other, larger projects and draw on the practical experience we have gained.” says Jan Wurzbacher, Climeworks co-founder and managing director.