A relevant climate mitigation strategy
Recently, I have been doing a lot of personal studies about climate change and different ways to tackle this global challenge. Professionals around the world have written a lot about different approaches to reducing global warming and transitioning the world to net-zero carbon emissions. We all know about the negative impacts of global warming on the environment and our lives, so it makes sense to find a lasting solution to this problem.
Global warming is caused by greenhouse gases (gases that trap heat in the atmosphere). Methane, carbon dioxide (CO2), nitrous oxides, and fluorinated gases are all greenhouse gases. However, carbon dioxide (CO2) is the most common greenhouse gas and the leading cause of global warming. CO2 is emitted when carbon-rich fuels are combusted (‘burnt’) to generate energy that supports our daily activities. This means that the continuous emission of this gas is going to lead to more global warming. It’s quite intuitive to infer that if this gas is prevented from been emitted or somehow removed from the atmosphere then our planet should not warm very badly. In fact, this approach exists and is called carbon capture and storage, CCS for short. It is also CCUS, the ‘U’ means utilization (more on this later).
How CO2 contributes to Global Warming
CO2 creates a blanket around our atmosphere that prevents heat from escaping. Just think of how warmer you feel when you're under a duvet, that’s exactly how the earth feels surrounded by CO2, ‘warm’. Unfortunately, excessive warming is undesirable as it leads to climate change which causes sea levels to rise and heatwaves that can have terrible consequences on our health.
Understanding Carbon Capture ‘Utilization’ and Storage
Carbon capture and storage is exactly what the name implies: capture CO2 from emitting sources and store it or use it. Capture technologies that can be used in industrial power plants include post-combustion capture, pre-combustion, and oxyfuel combustion. CO2 can also be captured directly from the air; this is known as direct air capture (DAC). In DAC, CO2 is ‘sucked’ right out of the air the same way trees absorb CO2 for photosynthesis.
After the CO2 is captured, it is transported through pipelines or ships to be stored underground in depleted oil reservoirs or saline aquifers. CO2 can also be stored in form of mineral carbonates. Carbfix, a company in Hengill, Iceland developed a method to turn CO2 into calcite rock by injecting the CO2, mixed with water, into underground basaltic formations. Under intense underground pressure and chemical reactions, the CO2 is transformed into a rock within two short years. Storing CO2 this way is a more permanent and safe approach.
CO2 can also be used for enhanced oil recovery (EOR), which basically means improving the production of oil from reservoirs by injecting CO2 into the reservoir. It can also be used as a feedstock for the production of clean hydrogen, cement concrete, fertilizers, and many more CO2-based products. In fact, there is a growing market for CO2. In a report by McKinsey & Company, it is estimated that by 2030, CO2-based products could be worth between $800 billion and $1 trillion, and the use of CO2 for producing fuel, enriching concrete, and generating power alone could reduce greenhouse gas emissions by a billion metric tons yearly.
CCS role in decarbonization and transitioning to net-zero emissions
Fossil fuels will still provide a significant portion of the world’s energy in the foreseeable future, especially in developing countries where consumers cannot afford the huge energy costs associated with renewable energy technology, at least for now. Therefore, completely replacing fossil fuels as a means to combat climate change is certainly not a very economical approach. Incorporating CCS as part of the global climate change mitigation strategy presents a much cheaper route to net-zero carbon emissions.
There is international consensus that CCS will play a critical role in climate change mitigation. Climate models by the International Energy Agency (IEA) show that carbon capture will need to contribute about 14% of CO2 emissions reduction between 2015 to 2050 and 17% from 2050 onwards to meet the Paris agreement. Just in case you're wondering what ‘Paris agreement’ means, here you go:
The Paris Agreement is a legally binding international treaty on climate change which aims to limit global warming to well below 2 degrees, preferably to 1.5 degrees Celsius, compared to pre-industrial levels.
Furthermore, according to the US department of energy (USDOE), CCUS technology is necessary to meet climate change mitigation goals at the lowest possible cost to society. The Intergovernmental Panel on Climate Change (IPCC) has concluded that without CCUS, the cost of climate change mitigation will increase by 138%, and meeting the Paris agreement may be impossible. In the absence of CCUS, the additional investment required for climate change mitigation in the electricity sector is a whopping $2trillion in the next 40 years.
Challenges and Enablers
Although theoretically, snatching CO2 from industrial sources or directly from the atmosphere sounds like a walk in the park idea, the technology has not yet been implemented on a large enough scale to have a profound effect on global warming. This is because there are challenges associated with implementing the technology on that scale. Currently, there are only 23 large-scale CCS facilities in operation or under construction capturing almost 40 million tonnes of CO2 per year. This rate falls significantly short of the 7 billion tonnes of CO2 per year the US department of energy says will be needed to meet the Paris goal.
The IEA has confirmed that for every successful CCUS project, there are at least two large scale projects that have been cancelled. The high cost of CO2 capture, a lack of infrastructure, relative absence of policy incentives, and lack of public acceptance is cited by professionals as some of the challenges facing CCS technology. In addition, the growing public outcry, reinforced by climate activists, for fossil fuels to be banned in order to ‘save the climate’ discourages companies from investing premium dollars in what would yield little to no return on their investments.
Some enablers of CCS includes tax credits for companies willing to invest in CCS, adequate carbon pricing, government regulation and policies, and educating the public to build confidence and acceptance. Another enabler will be the development of more CO2-based products such as varieties of chemicals, concrete, and fuels. If the high energy cost associated with turning CO2 into the aforementioned products is reduced, the market value for CO2 will rise which will encourage more companies to go into the business of capturing carbon dioxide for sale.
As the challenges of CCS are addressed and more facilities built, along with other climate mitigation strategies like incorporating renewables and hydrogen in the energy mix, the world will enter an era of unprecedented energy sustainability and be on course to achieve our ambitious climate goals.