What does CO2 actually do? A scientific look at the molecule
Reading time: 5 min
Carbon dioxide (CO2) has become a synonym for climate change. But there’s nothing fundamentally bad about the molecule itself: carbon dioxide is an important part of the natural carbon cycle. Small amounts of the colorless gas are found in the air we breathe.
It also plays a special role in its function as a greenhouse gas as it absorbs part of the heat radiated by the Earth into the cosmos and reflects it back onto our planet. Plants use CO2 for photosynthesis and, with the help of sunlight, convert it into carbohydrate and oxygen, which is then released into the environment.
“Carbon dioxide has always been part of our atmosphere and is created when any kind of combustion or oxidation occurs: from the cellular respiration of living beings, from a campfire, when brewing beer, or in a combustion engine, to name just a few everyday examples”, explains Andreas Wagner, PhD student at the Christian Doppler Laboratory for Sustainable SynGas Chemistry at the University of Cambridge.
CO2 as a resource
As an important resource, carbon dioxide is used in a variety of different ways. Christian Pichler, Postdoctoral Researcher at the Christian Doppler Lab:
No plant could grow without CO2. Carbon dioxide also has technical applications – it’s used to cool dry ice, in fire extinguishers, in the food and drinks sector to carbonate drinks, or as a solvent. This so-called supercritical carbon dioxide exhibits special properties when subjected to pressure and temperature that are used for tasks like decaffeinating coffee.
Christian Pichler, Postdoctoral Researcher at the Christian Doppler Lab
Carbon dioxide has attracted special attention in relation to global warming. As one of the greenhouse gases, CO2 serves alongside water vapor, methane and laughing gas as the Earth’s natural thermostat. It is indisputable that an increase in the concentration of greenhouse gases leads to an increase in the Earth’s temperature.
“In order to keep global warming as low as possible in line with the ambitious 1.5°C Paris climate target, we need to reduce CO2 emissions to net zero by around 2060 and (depending on the scenario) keep them at net zero or even go negative, i.e. reduce the CO2 content in the air. The simplest way of helping to do this is to save energy. That’s possible today; it doesn’t require any new technology”. At the same time, research is underway to see how new and alternative energy sources can be used without emitting any additional CO2. Scientists cite the example of the electrification of industrial processes, which amounts to a high share in the worldwide energy consumption. “This calls for power from renewables, i.e. solar, water or wind power”. Andreas Wagner continues:
While more and more renewable energy is being produced in the form of electricity, problems still arise when it comes to storage. Batteries will play a role in storing part of this electrical energy, but it would be better to initiate chemical reactions with electricity and convert the power into hydrogen or other energy-rich molecules that can then be stored and reused later on.
Andreas Wagner, PhD student at the Christian Doppler Laboratory
Andreas Wagner concludes: “This means we have to find ways of bringing together sustainable power production and sustainable fuel and chemical production”.
Processing CO2 in a way that makes sense for the environment
And this is precisely what Andreas Wagner and Christian Pichler are working on together with their colleagues at the University of Cambridge under Professor Erwin Reisner. Their research covers multiple aspects of CO2 conversion with the goal of using carbon dioxide sustainably on the path towards a circular carbon economy. Here the two chemists are exploring whether power from renewables or from sunlight can be used to cause chemical reactions to split water or produce syngas as efficiently as possible. What’s more, they are developing new photocatalysts and attempting to produce products for the chemical industry out of biomass and plastic waste, while producing hydrogen at the same time. Today syngas – a gaseous mix of carbon dioxide, hydrogen and crucial chemical feedstock for producing fuel – is mainly made from fossil fuels, “that’s why we are trying to find new approaches to producing syngas in an environmentally sound way from carbon dioxide and water”, explain the two researchers.
What does this mean for the future?
“Forecasts are always a bit difficult”, the two agree. “But I think that the electrification of our society and industry is inevitable”, says Andreas Wagner. In order to be more efficient in terms of CO2, however, it will be necessary to expand production of renewables, develop alternative energy sources and make sure suitable storage options are available (which may be in the form of future technologies like Power2Gas and electrolytic hydrogen). The scientists say that another option would be to suck up the surplus CO2 from the air and store it in the ground, where it will either retain its form as a gas or fossilize into calcium carbonate. “Here major research projects are currently underway to find the best way for this to function”, says Christian Pichler.
What is OMV doing in this sector?
OMV engages in proactive carbon management at several levels. On the one hand, OMV is reducing the CO2 emissions of its business activities by optimizing technical processes, through the gradual, consistent end of routine flaring and the construction of a photovoltaic plant to meet the company’s own demand in Austria. On the other hand, OMV is reducing the carbon footprint of its products by increasing the ratio of gas to oil in the portfolio and, for example, through highly efficient Co-Processing of biogenic components in fuels. Furthermore, OMV is working on innovative technologies for chemical processing and for the underground storage of CO2, as well as researching technologies that will allow us to offer hydrogen in the future.
OMV has established a dedicated department called New Energy Solutions in order to dynamically develop these multifaceted activities and manage them efficiently. This department will bring together all of the different threads related to developing low-emission technologies. And these technologies will play a significant part in the future success of OMV.