Michelle Eichenberger

In an effort to keep temperature rises from exceeding 2°C compared to preindustrial levels, many nations of the world including Switzerland have committed themselves to a net zero target by the year 2050. Although technology is in place to help achieve this goal as a global society, it is dangerous to believe that we can solely rely on technological inventions to resolve the threat that is climate change.

The problem at hand

In 2015 a treaty was finalized with a primary goal to tighten global measures against the imposing threat of climate change. The treaty in question is the Paris Agreement. Signed by 193 parties, amongst which are Switzerland, the United Nations, China and many more, the treaty sets a global goal to keep temperature rises well below 2°C compared to preindustrial levels. This goal matches the representative concentration path (RCP) 2.6 (Unfccc, 2016). One of the key aspects of the acceleration of climate change is the anthropogenic emission of greenhouse gases  with long half lives in the earth’s atmosphere and therefore cause a gradual warming, as they inhibit thermic radiation from exiting the atmosphere. One of the most important greenhouse gases is Carbon dioxide (CO₂).  As we burn fossil fuels in everyday life, we release it into the atmosphere at a constant rate. In addiotion with the reduction of vegetation area and the warming of the oceans we simultaneously also weaken the earth’s natural sources for CO₂ storage (Brander M, 2012). So, in order to reach the goal, set in the Paris Agreement there must be a vast reduction in CO₂ emissions in the next couple of years, which is why many nations have set themselves the legally binding target of zero net emissions by the year 2050 (BAFU, 2021).

CCUS and its cruxes

CO₂ emitting activities are embedded in everyday life and in every sector of society. To hope that all of this can be brought to a rather abrupt halt is sadly unrealistic and even the reduction on a smaller scale shows to be quite challenging. As a matter of fact, some estimates of temperature rise predictions still expect an increase of 2.9°C under current measures (Action Tracker, 2021). So if we want to reach our goal of keeping temperature changes below 2°C, simple reduction of emissions might not be enough. In the last decades technology has been developed that allows to extract CO₂ directly from production processes. This further reduces the concentration of CO₂ in the atmosphere. What is known under the name “Carbon Capture Utilization and Storage” (CCUS) are a number of methods to extract CO₂ and either recycle it into new products, such as fuels, chemicals or materials (CCU) or store it away and therefore keep it out of the system for good (CCS). Carbon capturing can either take place after the emission, meaning the gas is extracted from the atmosphere (DAC – Direct Air Capture) or it is being inhibited from entering the atmosphere in the first place by removal during the industrial process. Such technologies are very efficient, they can remove more than 95% of the CO₂ that would normally be emitted. Carbon capturing from air is not quite as efficient but with 70 – 80% the quota is still very good. In CCS the carbon captured is being transported most commonly via ship or pipeline and then stored underground in fitting geological formations (Figure 1) (Wilberforce et al., 2021).

Figure 1: Illustration of CCU and CCS processes  (Energy Agency, 2020)

In Europe, especially around the North Sea basin a lot of large-scale CCS projects are already running. For example, in Norway the Sleipner and Snøhvit storage site have been storing 22 million tons of CO₂ ever since the start of operation in the mid-nineties. Projects in the Netherlands as well as in Ireland have also been successful in storing CO₂. CCU on the other hand is a rather new industry and not yet as commercially established as CCS. The idea is to convert the captured carbon into a new product for example as fuel, as solvent or as chemicals. In Iceland for example there already is a small commercial-scale plant which converts captured CO₂ into methanol for fuel (CCSA, 2020).

So far, we’ve established, that functioning technology is in place and is being put to practical use in this very moment. It appears CCUS seem to be a very viable solution to the crisis, so much so that it is almost too good to be true. So where is the catch?

Although the technology has been established, in CCS more so than in CCU, the road to a large-scale global commercial success is still very long. The main barrier for capturing technology are the high costs of CO₂ capture at industrial sites and power plants. Aside from capturing costs the transport of CO₂ also poses some challenges. A good infrastructure that allows for efficient transport and storage of CO₂ is the backbone of a commercial decarbonization strategy. A good, networked pipeline system is key, this includes not only the geographical connections but also the safety of pipes specialized for CO₂ transport, withstanding CO₂ density and pressure. In order to guarantee this, there still needs to be further assessment.  To enable all of the needed changes, constructions and assessments, there needs to be not only sufficient funding but also clear legal frameworks that allow for cooperation between nations and companies. The last piece of the puzzle are storage and utilization capacities. As of yet it is unclear how much of a liability the stored CO₂ poses. Investors and governments still need to assess how to deal with the long-term risks of CO₂ storage. As for utilization methods, the technology is not yet as refined as to compete with storage. In addition to that many CCU methods are very expensive and require a lot of energy, more than they provide in the end. It also should be mentioned that CCU is emission neutral, meaning the CO₂ is not actually extracted from the cycle, it is simply being reused, therefore no additional CO₂ enters the system but there is no direct reduction with this technology. These factors explain why, although this technology is being used since well over twenty years, there still has not and might not be for some time a commercial application for CCUS in a scale big enough to vastly relieve pressure on emission reduction strategies (CCSA, 2020).

In conclusion…

CCUS technology must definitely be taken into serious consideration for future emission management strategies, since reducing alone is not only an environmental but also a political and economic challenge. But to think, that CCUS technology is a golden ticket to get out of this crisis could be just as dangerous as disregarding it entirely. Although the methods are very successful and efficient there are still many hurdles for this technology to not only countervail current emissions but eventually override them to ensure a total reduction of CO₂. Putting too much emphasis on technological solutions alone imposes a risk of carelessness. The chance offered by this new technology is not an excuse to slack off on efforts of reducing, it is rather a ray of hope for us to bring global warming to a stop while we’re still within our goal of 2°C temperature increase.

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