• Reducing emissions alone will not be sufficient to achieve net zero.
  • Capturing CO2 will also play a big role - but the CO2 we store can now be used as a raw material in an increasing number of applications.
  • Many CO2-based products are already on the market.

Net-zero – a climate-neutral world – seems to be achievable with the greatest of efforts, at least technologically. But above all, one thing is clear: reducing emissions alone is not enough to achieve this goal.

This applies in particular to industry, which represents a significant proportion of the greenhouse gases that we humans produce. For some sectors it is extremely difficult, if not impossible, to completely avoid CO2 emissions; when manufacturing cement, fertilizer or steel, for example. Additional approaches are needed in these cases.

The most common idea at the moment is to capture the emitted CO2 and so reduce the total amount in the atmosphere step by step – so-called carbon dioxide removal (CDR). For years, this has had its place in the toolbox of the Intergovernmental Panel on Climate Change (IPCC). There is a wide range of ideas about how to remove the gas and what to do with it. For example, we can plant more trees and regenerate bogs that absorb CO2, albeit at the risk of droughts or fires eventually releasing it. Or we can bunker CO2 in the oceans, which would have the side effect of seawater becoming even more acidic.

All these bold geo-engineering ideas have their pros and cons, of course, but they should not be simply dismissed. For example, on the way to a hydrogen economy, we may need to store CO2. At the moment there is not enough renewable electricity to produce emission-free 'green' hydrogen on a large scale. Its 'blue' sister could be a bridge technology: producing hydrogen from natural gas, with the CO2 produced being separated off and permanently stored.

Using CO2 as a new raw material

But I suggest we should also think in a very different way. We don't have to see CO2 as simply an enemy we're supposed to get rid of and lock away. Why not imagine it as a kind of friend and helper? After all, we can actually do something with the exhaust gas that escapes the factory vents – by using it as an environmentally friendly new raw material, for example. We can use it in the manufacture of building materials, plastics, and many important basic chemicals, such as methanol, to name but a few possible examples.

Experts call this carbon capture and utilization (CCU), an idea that is becoming increasingly popular. However, this has not captured the public's attention. This is one more reason to put a spotlight on recycling CO2 at the COP26 climate summit in November.

There are several ways to make use of residual CO2
There are several ways to make use of residual CO2
Image: LTT, RWTH Aachen University

Politicians have already recognized the potential of CCU in many places. For example, the German government has long been promoting numerous research projects, and CO2 recycling also plays a role in the European Green Deal. Now we need to further improve the framework conditions that help obtain vast amounts of low-cost green electricity, and to design CO2 emission costs in such a way that CCU becomes competitive.

The missing piece of the climate protection puzzle

Science and business have high expectations around the topic and are driving it forward. The Global CO2 Initiative, for example, is a network of experts from the University of Michigan working to make CO2 capture a mainstream climate solution. CO2 Value Europe is an association of numerous research institutions and companies pursuing the same goal. Everyone agrees: CCU is the piece that can complete the climate protection puzzle. Worldwide, CO2 is already being used as a raw material in a growing number of applications and sectors – and the trend is rising sharply.

CCU is a particularly important topic for the chemical and plastics industry. This sector needs carbon for its products; currently it obtains it from fossil sources, such as oil. As a result, the industry represents around 6% of global CO2 emissions. So it as clear that on the road to climate neutrality, carbon must come from other, emission-free sources. Recycled plastic waste, biomass – and CO2.

In the meantime, increasing numbers of plastic components derived from CO2 instead of petroleum are making their way to market. Foams for mattresses and car seats, glues for sports floors, fibres for textiles and much more can all be produced using CO2.

Taking nature as a model

It's not just large companies; more and more start-ups around the world are using CO2 in their production. They take nature as their model and imitate what plants have been doing for millions and millions of years: converting CO2 and water into sugar and oxygen with the aid of solar energy. For example, a young company from Finland, Solar Foods, is using this process to produce a protein powder that will serve as a food supplement.

CO2 is obtained mainly from production exhaust gases. Although this does not increase emissions any further, it does not reduce the total amount of CO2 in the atmosphere. But you can also extract the gas directly from the ambient air, and some companies are pioneering this approach.

The IEA estimates that around 40 million tonnes of CO2 is currently captured using CCU –but its potential is much higher. According to experts, this ranges from 100 million tons to 15 billion tons per year. In comparison to the roughly 33 billion tons that humans currently put into the atmosphere each year, this is not a negligible amount. Together with the shift to the circular economy, CCU is an option that we should definitely consider in order to reach our most important goal: net zero.