THE RISE OF CLEANTECH
The cleantech sector is attracting large investment, with companies pushing boundaries to capture, store and re-use CO2. In this space, nothing comes easy, but the potential pay-offs are plentiful
Tech companies are working to capture, store and re-use CO2. But in this space, nothing comes easy.
We can safely define excess emissions of carbon dioxide as humanity’s single largest negative influence on global climate. International efforts to reduce emissions have led to a wide variety of measures to limit the problem, including investments in technology and businesses that aim to improve environmental sustainability – otherwise known as the clean technology sector, or cleantech for short. Thanks to cleantech, we now have a variety of ways (at various degrees of readiness) to reuse carbon and extract CO2 directly from the air, be it for carbon storage, plant growth or the production of synthetic fuels.
Lately, cleantech has seen an explosive increase in investment, with start-ups, well, starting up across a wide range of sectors. This can only be good news. The World Meteorological Organization’s (WMO) 2020 report on greenhouse gases stated that the atmospheric concentration of CO2 reached another record high in 2018 – 407.8 parts per million (ppm), up from 405.5 ppm in 2017. The report goes on to say that CO2 remains in the atmosphere for centuries and in the oceans for even longer. ‘There is no sign of a slowdown, let alone a decline, in greenhouse gas concentration in the atmosphere, despite all the commitments under the Paris Agreement on Climate Change,’ said WMO Secretary-General Petteri Taalas. ‘We need to translate the commitments into action and increase the level of ambition for the sake of the future welfare of mankind,’ he continued.
A HOPE IN CLEANTECH
‘We need to translate commitments into action and increase the level of ambition for the sake of mankind’
Raising ambitions is where cleantech comes in, with many companies now seeking to take existing technology a step further. The best-known technology for preventing excess carbon entering the air is currently CCS – carbon capture and storage – which is designed to extract CO2 directly from the emission source at production facilities and place it into some form of long-term storage. But, aside from the fact that it isn’t yet widely employed, CCS has a downside – it can’t capture CO2 that has already been emitted. Several companies are now racing to develop methods to reduce the existing concentration of greenhouse gases in the atmosphere by extracting CO2 directly from the air. The technology, known as direct air capture (DAC), is currently being developed by, among others, the Swiss company Climeworks. Climeworks produces a module called a CO2 collector – an electricity-driven turbine whose in-built filters separate CO2 from the rest of the air. The filters are then heated up to between 80°C and 100°C, which releases the CO2 molecules for capture. ‘Each turbine can collect up to 50 tonnes of CO2 per year, but we can stack them into larger units,’ explains Louise Clark, head of communications at the start-up. ‘Our first facility in Zurich consists of 18 units – meaning 900 tonnes per year. This corresponds to the amount of CO2 emitted from a few thousand households.’ Climeworks has set itself the goal of extracting and capturing one per cent of the world’s CO2 emissions by 2025.
CO2 collected by the units in Zurich is sold and sent directly to a local greenhouse, which uses the captured gas to stimulate plant growth. ‘But plant growth is only one of the uses for the CO2 we collect,’ says Clark. ‘Another exciting effort is the potential to use recycled CO2 to produce synthetic fuels.’
FROM AIR TO FUEL
Producing synthetic, carbon-based fuel using recycled CO2 is a relatively new notion. It’s being developed by Carbon Engineering in Canada and Norsk e-Fuel in Norway, among others. The latter is a consortium made up of several tech companies – including Climeworks and its DAC units.
European transportation still relies heavily on fossil fuels and while the ultimate goal is to electrify large parts of the sector, aviation and larger bulk transportation will likely require liquid fuels for combustion engines for some time to come.
Norsk e-Fuel’s answer is to build a so-called powerto-liquid factory at Herøya Industrial Park in Norway that will use electricity from renewable sources to produce an alternative fuel based on CO2 and water. The plan involves using Climeworks’ DAC units to collect the required CO2 and, with the help of hightemperature electrolyser technology from a company called Sunfire, convert it into syngas, a mixture of hydrogen and carbon monoxide. This mixture can then be converted into a substitute for crude oil that can be further refined into vehicle fuel.
‘We plan to have the first facility commissioned during 2023, with an estimated production volume of ten million litres of renewable crude annually,’ says Karl Hauptmeier, managing director of Norsk e-Fuel. ‘We then plan to increase production ten-fold, producing a volume of 100 million litres by 2026. The resulting fuel will have the same qualities as regular jet fuel and diesel, and can therefore be distributed through the existing infrastructure.’
This process isn’t easy. Climeworks is closely involved
in the planning for the project, but only around 15–20 per cent of the CO2 for the fuel will be extracted from the atmosphere through the Climeworks units. The rest will have to come from carbon capture from direct sources in the nearby industrial area, meaning that it will still rely on the burning of fossil fuels. This is partly because DAC is expensive and also because CO2 is produced in much higher concentrations directly from industrial processes than is found in air – ten per cent versus 0.04 per cent – which makes traditional carbon capture much more efficient.
Another drawback is the fact that the entire process demands large amounts of electricity, meaning affordable power is a necessity to keep the cost of production down. This would also need to come from renewable sources in order to prevent the use of yet more fossils fuels. According to Hauptmeier, this is what makes Norway the right location. ‘Norway’s supply of renewable energy is perfect for this type of project,’ he says. Indeed, several cleantech start-ups with large power requirements have chosen to base themselves in Norway for just this reason.
However, although Norway’s power production is 98 per cent renewable, roughly 46 per cent of the energy that flows from the country’s sockets still comes from fossil fuels because the country is connected to the European power grid. Norwegian electricity producers using renewable sources are issued green certificates that are sold all over Europe to companies and organisations that want to boast about using green energy. This means that, in theory, Norwegians who purchase electricity without these certificates are left with a standard European electricity mix. (In practice, it’s not quite so bad. As electricity travels the path of
‘Norway’s supply of renewable energy is perfect for this type of project’
least resistance, the supply in Norway will still have a higher percentage of renewable energy.)
The very concept of synthetic fuels has also been criticised for allowing continued use of combustion engines when society should be seeking to transition to electric vehicles as soon as possible. Additionally, it might seem futile to use extracted CO2 in fuel, which ultimately sends the carbon back into the atmosphere after combustion. Holen counters this argument by explaining that the company wants to focus sales on the transport segment that’s most difficult to electrify – heavy transport such as airplanes and cargo ships. But it just goes to show, being clean isn’t easy.
FROM AIR TO ROCK
Back at Climeworks, Louise Clark says that despite the high cost of DAC technology, the company has seen considerable interest from other potential partners. It has installed a DAC unit in Italy, where CO2 is sold to producers of carbonated drinks. Another project is underway in Iceland, where extracted atmospheric CO2 is sent to underground storage.
Carbfix, a subsidiary of Reykjavik Energy, captures and stores CO2 emissions from geothermal power production – Iceland’s main source of energy. The gas is then mixed with water and sent underground for storage. In 2017, Carbfix started a venture with Climeworks to combine the two technologies. Climeworks installed a DAC unit at Reykjavik
Energy’s Hellisheidi geothermal plant and the CO2 it extracts from the air is sent into storage using the Carbfix process.
‘We take CO2 from both sources and mix this with fresh water. The carbonated water is then sent several hundred metres down underground, in the underlying basalt,’ says Ólöf Baldursdóttir from Reykjavik Energy. ‘This rock type is porous and the carbon-rich water fills up the air pockets. Tests show that this is mineralized into solid rock, namely calcite, in about two years – and this is much safer and stable storage than storing it in the form of gas.’
Baldursdóttir walks me around the facility outside Reykjavik, enthusiastically pointing towards turbines, pipelines and tanks – all working together to send gas for storage underground. For the time being, there is only one Climeworks unit collecting atmospheric CO2 here, but there are plans to expand. Both partners report being satisfied with the results.
Baldursdóttir admits that the current contribution from the DAC unit won’t have a significant effect on the climate, but is keen to point out that the success lies in the fact that it works at all. ‘What we do won’t be sufficient to fix the world’s climate issues, but it is one of many contributions that might help,’ she says.
COMBINING BIOENERGY AND CARBON STORAGE
In the race to extract carbon from the air around us, bioenergy with carbon capture and storage (BECCS), offers another potential option for the storage of atmospheric CO2. The goal is to combine carbon capture with power production from bioenergy, in which electricity and gas are generated from organic matter such as plants and food waste.
The original source of the bioenergy, vegetation from forest and agricultural areas, absorbs CO2 from the air during the growth phase. This material is then sent to facilities for power production. The plan is to capture the emissions from this process directly at the source of combustion and then send them underground for storage. This energy production is referred to as ‘carbon-negative’ and is considered one of the more promising carbon-reduction efforts within cleantech. The concept has been incorporated into many of the IPCC’s conceptual models designed to reach the goals set in the Paris Agreement. The Royal Society recently estimated that early implementation of BECCS could reduce atmospheric CO2 levels by anything between 50 ppm and 150 ppm.
The technology’s Achilles heel is the need for huge areas for biomass production. It’s estimated that the world would need between 3.2 and 9.7 million square kilometres for BECCS to contribute enough to reach the desired effect – which translates to the land areas of India and Canada respectively. Unsurprisingly, there’s a certain amount of scepticism within scientific circles as to the feasibility of BECCS, especially when the need for land for food production is taken into account. Furthermore, to date, there are only 17 facilities in the world with the capacity to store up to a million tonnes of carbon per year. Considering that the world’s total CO2 emissions in 2017 were 38 billion tonnes, that’s clearly nowhere near enough.
Tyre fires are a huge source of emissions; tyre graveyards are known to be perfect breeding grounds for malaria mosquitoes
RECYCLED CARBON
There’s another angle to the cleantech sector. As well as capturing and storing CO2, some companies are looking at ways to recycle it. Reusing carbon-based products could lower the need to produce and use more fossil fuels. Carbon black is one example of this. Often forgotten in discussions around fossil fuels, carbon black is also often wrongly confused with regular soot. However, the substance is actually an industrially derived petroleum product that’s used in the production of car tyres, paint, plastics and ink. It’s traditionally produced through the incomplete combustion of crude oil, which causes large-scale pollution and emissions.
‘To produce one kilo of carbon black, you need 2.5 kilos of crude oil. The tyre industry alone needs more than seven million tonnes of carbon black,’ says Troy Huijskens, a business development manager at Dutch cleantech start-up Black Bear Carbon. ‘It’s a given that this is a huge contribution to the problems surrounding greenhouse gases.’
Black Bear Carbon has developed a technology to recycle old car tyres and split them into carbon black, oil and gas. The tyres are divided into smaller and smaller pieces before undergoing pyrolysis, which separates the different components. The carbon black,
which makes up 40 per cent of the tyre, can then be sold to producers of tyres and paint who previously purchased carbon black derived from crude oil.
‘Oil derived from the tyre leftovers is used to power the facility, making us a circular economy,’ says Huijskens proudly. ‘We estimate that one of our plants might save carbon and CO2 equivalent to one million trees. Our goal is to have 1,000 facilities around the world – ergo one billion trees.’
In addition to lowering emissions and the use of fossil fuels, used tyres are a global waste issue that exacts a heavy toll on the environment. Tyre fires are a huge source of emissions and in the tropics, tyre graveyards are known to be perfect breeding grounds for malaria-carrying mosquitoes.
Unfortunately, as Huijskens explains, recycled carbon black still falls short when it comes to the manufacture of new tyres for cars. Tyre producers require several different grades of carbon black; recycling currently only allows for the recreation of some of these grades. Nevertheless, recycled carbon black can still be used by producers of bicycle tyres, ink and paint, who would otherwise have a large consumption of fresh crude oil.
Caveats similar to those raised earlier also arise. Even if Black Bear Carbon has a green, environmentally friendly label, the product upon which the company is based – car tyres – has a highly polluting life cycle, with both CO2 and microplastics as byproducts. But at least the addition of recycled carbon black in the production cycle offers a less-hostile climate option than standard production.
COLLECTIVE EFFORTS
Cleantech sits well in the modern finance industry’s environmentally friendly narrative. It provides an arena for investments looking for a green label. It also provides some hope. The latency of CO2 in the atmosphere and the ocean means that greenhouse gases will circulate within these systems for several hundred years. We know that reducing emissions alone may well not be enough to keep climate change at ‘safe’ levels, given the quantities present in the atmosphere. Nevertheless, it’s crucial to balance hope with realism, to take a practical view of each new technology. As Baldursdóttir says, a single project won’t fix the climate issue, but it can contribute positively towards the world’s collective efforts.