Toxic CO2 emissions are so prominent in our world today, with industrial processes responsible for 248.8 million tonnes of pollution in 2019 being released in Malaysia alone and 33.1 billion metric tons of CO2 emissions on a global scale. At these unprecedented levels, exceeding the Global Carbon Budget and surpassing Paris Agreement target of staying below global warming at 1.5℃ this century, is seeming more and more likely. Increases in global mean temperatures will result in detrimental effects such as significant changes in the intensity, frequency and location of extreme events such as heat waves, flooding, wildfire and tropical cyclones. Scientists are fighting to save humanity by combating climate change through implementing different technologies such as CCS and renewable energies in order to prevent these deleterious circumstances from occurring. However, with the discovery of many new technologies, the main question lies in determining which strategy will have the greatest influence on lowering CO2 emissions alongside being highly cost effective and practical.

What is CCS and how obtainable is it on a global scale?

Carbon capture and storage technology, more commonly known as CCS, is a technology where carbon dioxide is captured from the air and stored in deep geological strata to prevent the CO2 from being emitted into the atmosphere and contributing to the greenhouse effect. It works by capturing CO2 emissions from power plants and industrial facilities, then compressing and piping it to suitable storage sites. When the CO2 is compressed, it is turned into a dense fluid and the CO2 displaces water when it is trapped within the rock. Captain stone is the main geological storage area being used as it is located around 2400 m below sea level hence being highly unlikely for CO2 to escape and re-enter the atmosphere.

Currently, there are 51 facilities in our world today: 19 in current operation, 4 under construction, and 28 at different stages of development. These 51 facilities have an estimated capture capacity of around 96 million tonnes of CO2 per annum. Each facility reduces CO2 emissions by approximately 80% - 95%, if CCS is implemented in developing countries by 2050, the net zero emissions target is likely to be attained. There are 3 types of CCS: carbon negative CCS, near carbon neutral CCS and carbon positive CCS. The difference between these, is quite simply, in their names. Negative carbon emissions is where there is a negative balance of emissions into the atmosphere. BECCS (Biomass energy with CCS) alongside direct air capture are both examples of carbon negative CCS. The diagram below shows how the respective technologies work.

Decatur CCS facility (Illinois, US) uses a bio refinery method by converting biomass into ethanol. The ethanol produced is blended with petrol or gasoline that is used as fuels in motor vehicles. The pilot scale in Iceland utilises direct air capture. Air passes through the CCS facility and leaves containing less CO2. Both of these lead to negative carbon emissions as carbon dioxide is taken out of the atmosphere in the process. Carbon positive emissions, on the other hand, is where there is a positive balance of emissions into the atmosphere, meaning carbon is still emitted in the process. Quest CCS facility in Canada is an example of a carbon positive CCS technology. It transforms oil sands to petrol. CO2 is produced in the process but captured and stored away. Although there are still carbon emissions, the levels significantly reduce as compared to without CCS. Near carbon neutral CCS is similar, though levels of carbon emissions are lower than carbon positive strategies. Carbon free energy vectors such as electricity, hydrogen or heat from natural gas, oil and coal are near neutral carbon as even though they don’t emit carbon, the extraction process causes an emission of carbon hence being classed as ‘near neutral’. The Boundary Dam CCS facility, in the state of Saskatchewan, Canada uses coal to produce electricity, a carbon free energy vector. 10% enters the atmosphere whilst 90% of carbon is stored thus being a near carbon neutral CCS.

However, with every positive comes its flaws:

There are still doubts about the CCS technology strategies as there is minimal conclusive research about the absolute security of the underground carbon dioxide storage. Since the carbon dioxide is compressed at high pressures there are reasons to be concerned about the safety associated with the storage. Investing in close monitoring of the storage sites is highly recommended by many scientists until a complete detoxification of the area becomes possible. Even though captain stone is 2400m below ground level, there are still the possibilities of encountering leakages. Leakages of high quantity at such sites would make the air largely unbreathable as CO2 is highly toxic.

CCS in the industrialized world:

If CCS were not to be available as a technology, the cost of reaching 2ºC of global warming would likely increase by 50 to 200%. As shown in the pie chart, fossil fuels and industrial processes make up for 65% of the total greenhouse gas emissions in the world. The main manufacturing industries that make up the majority of CO2 emissions are the cement industry and steel manufacturing industry. Cement is basically paste that allows sand, gravel and crushed stone to bind together. Limestone is a hard rock and clay combined with other minerals which requires heat of up to 1400℃ for the chemical reaction to occur in order to produce new rock-like minerals. 60% of CO2 emissions comes from the production of limestone whereby calcium carbonate decomposes to make carbon dioxide and calcium oxide under high heats. There is no alternative to using limestone for making cement as it is an essential component. It is a crucial part of our lives as it is practically irreplaceable in the construction industry, and so scientists predict CCS needs to be implemented on at least 20-30% cement production facilities globally to reduce carbon emissions effectively. In the steel industry, approximately 1.5 - 3 tonnes of CO2 is produced for every tonne of steel. Blast furnaces are used to physically convert the iron oxides, containing iron ore, into nearly pure liquid iron. There is no alternative to using coking coal (carbon) in blast furnaces hence makes the use of CCS in that industry unavoidable to achieve deep cuts in CO2 emissions.

How viable is implementing the technologies?

There are 4 main stages in implementing new environmental technologies. The first stage is the rejection where society believes the technology is fictional. Secondly, comes the acceptance of technology; being able to recognise costs associated with implementing such a distinct and new technology into the world. The third stage is recognising the major costs but also understanding the cruciality in investing into it. Finally comes the routine, whereby the technology becomes a standard operating procedure in all processes. A few examples of technologies that have reached stage 4 are catalytic converters in cars and desulphurisation technologies for acid rain coal-fired power stations (SO2 is captured at source and prevents it from entering the atmosphere). Stage 2 and 3 often take decades. In the case of desulphurisation, it reports that it was stuck at stage 2 for 3 whole decades though once implemented, the reported costs are 5 - 10 times lower than anticipated and the costs have continued to decline since.

But, isn’t renewable energy and afforestation a more cost effective way of reducing emissions?

Planting trees, or 'Afforestation', is a simple and cost-effective way of removing carbon dioxide from the atmosphere. The existence of these trees must be guaranteed over a timescale of, at least, several centuries to ensure that the climate benefits are achieved. Increases in competition for land for food production could impact the food supply in the world and drive up the food prices and cause higher levels of famine and malnutrition in poorer countries. Alternatively, we could source 100% of our energy from renewable sources instead of fossil fuels. However, their production comes and goes on their own schedule, depending on sunlight and wind speeds. They cannot be dispatched on demand, in other words, it cannot be turned on and off as needed by the end-user. If we were to face anticyclonic weather conditions (several weeks of cold, windless winter across a country), there would be a high energy demand with a close to zero production from wind turbines, while levels of solar energy production would be consistently low. This means that in the lead up to the anticyclonic conditions, we would require being able to continuously release several weeks of energy storage. Being able to store this level of energy would be of a significant cost to countries hence CCS technologies would be more cost effective.

Replacing fossil fuels with renewable sources has clear benefits, such as increasing energy security or reducing the impacts of fossil fuel extraction. Whilst saying this, an over-emphasis on renewable energy could potentially divert our attention from the end goal: lowering carbon emissions. Investments in more balanced and efficient carbon reduction pathways such as CCS would pose as a much more safer bet in the long run, both in terms of cost and energy availability.

So, is attaining net zero carbon emissions in the world today too ambitious to hope for?

Ignoring the high levels of toxic carbon emissions from our energy sector puts humanity at the risk of irreversibly damaging our ecosystem. The main question lies in the practicality and cost effectiveness of available solutions. If CCS is implemented in developing countries, the climate change will likely remain below 1.5℃ this century. With this in mind, we need to consider the economic feasibility through understanding the concept of supply and demand in countries. Most firms are unlikely to want to change production strategies unless incentivised to do so. The incentives can take the form of subsidies or grants to compensate for the significant increases in costs of production from the extra excessive levels of energy expended on catalysing the capture technology. In order to ensure that the world is able to attain net zero carbon emissions, countries must abide by the Paris agreement alongside not only applying scientific technologies but also viewing it from a financial perspective to increase effectiveness. The International Energy Agency estimates that more than 2000 CCS power stations would be need to be installed in a scenario for less than 2◦C of climate change. With the invention of CCS alongside utilising the other current renewable technologies, there is hope for humanity in preventing the world from exceeding the carbon budget. However, this ‘potential’ can only be achieved if countries work as a collective unit to ensure that the necessary changes are made, before it's too late.