Ms Yekkaluri Snehasree Reddy
Research Intern IISD
Graduate Student of Chemical Engineering
JNTU, Hyderabad, Telangana

Though there is a global trend to opt for sustainable sources of energy, fossil fuel-based energy remains the most common and widely used source of power globally. The main reason is that they are readily available and have successfully met our energy needs till now. But fossil fuel poses many problems to the environment - the fossil fuel-based energy sector (transportation, electricity and heat, buildings, manufacturing and construction, and other fuel combustion) is a significant contributor to greenhouse gases - which cause global warming. During the various industrial activities, greenhouse gases are released into the atmosphere, they trap the sun's radiation, thus increasing the average global temperature - which leads to climate change, the rising of sea levels, the disturbance of animals' natural habitats, extreme weather conditions, melting of the polar ice caps, etc. Most emissions from all human activities predominantly contain carbon, and its abundance in nature compared to other greenhouse gases - make it the primary contributor to global warming.

Reducing greenhouse gas emissions has become a key goal for many developed and developing nations worldwide due to the increasing awareness about global warming, climate change, and shift towards sustainable economies. Intergovernmental Panel on Climate Change (IPCC) reports that without any drastic action to curb global warming, average global temperatures are bound to rise by 1.5oC by 2030 and 2oC by 2050 - causing an irreparable loss to the environment. These factors have led to accelerated research and execution of carbon capture technologies. The carbon dioxide capture and storage (CCS) process of trapping and safely storing carbon dioxide (CO2) would otherwise be released into the atmosphere. The main focus of these technologies is to trap the carbon dioxide directly from industrial sites and store them in underground tanks, utilizing it for producing commercially viable products such as calcium carbonate (Construction industry) or to grow plants. This technology enables us to use fossil fuels without the guilt of contributing to global warming.

Carbon Capture and Storage involves three main stages: capturing the carbon dioxide produced by industrial activity - the CO2 is separated from other gases produced in industrial processes, transporting the captured carbon dioxide - the CO2 is then compressed and transported via pipelines and huge containers to storage locations, and then storing it in underground tanks. The three most important types of carbon capture are Pre-Combustion, Post-Combustion, and Oxyfuel Combustion. A pre-combustion carbon capture system involves converting fuel into a gaseous mixture of hydrogen and carbon dioxide. This carbon dioxide is separated and compressed for storage. The post-combustion carbon capture system consists of dissolving carbon dioxide from exhaust gas after combustion. Oxyfuel combustion carbon capture system involves the use of oxygen for combustion of fuel - the exhaust gas contains a mixture of water vapor and carbon dioxide, which are subsequently separated for transportation and storage. This captured carbon dioxide can be stored in Rocks - Carbon dioxide is injected underground or porous rocks; Oceans - it could be injected into the deep ocean where the pressure is high enough that CO2 would dissolve; Minerals and CO2, when dissolved in water, forms a weak carbonic acid, this weak acid can react with the minerals in the surrounding rock to form solid carbonate minerals.

Carbon capture and storage system have several advantages other than reducing global warming: Generating additional power; The CO2 stored underground could be used to extract geothermal energy from that location; Additional fuel - CO2 can be readily converted into usable fuels like methane; Concrete enhancement - The captured CO2 can be used to improve the strength and durability of concrete; Chemicals - The captured CO2 can be used to manufacture a myriad of chemicals and plastics; Increasing employment opportunities - setting up a carbon capture facility will require a skilled workforce.

Many natural gas plants started implementing carbon capture to supply CO2 for enhanced oil recovery in 1972. The first large-scale project to inject CO2 into the ground was launched in the Sharon Ridge oilfield in Texas. The first-ever offshore large-scale carbon capture and storage plane was set up in Sleipner in Norway, where CO2 was separated from natural gas and injected into a reservoir under the North Sea. During the early stages, this technology was applied only in oil and natural gas processing plants. Still, today they have a wide range of applications in coal fire power plants, chemical industry, steel manufacture, etc. The number of carbon capture facilities has been increasing, the primary factor for this being that everyone realizes the repercussions of global warming and climate changes - many national governments are introducing laws and policies to limit carbon emissions. The United States of America, 45Q tax credits - section 45Q of the internal revenue code offers a tax credit for each metric ton of carbon capture. Norway made a considerable investment in capturing CO2 with a storage facility deep under the North sea. Climeworks has set up the world's first commercial carbon capture facility in Switzerland in 2017. Countries worldwide have started investing in research and implementation of carbon capture technologies - Australia, the People's Republic of China, Korea, the Middle East, and New Zealand. In 2020, there were a total of 20 commercial carbon capture plants around the world; these currently functioning facilities have the capacity of capturing and permanently storing 40 million tons of CO2 every year (Global CCS Institute 2020). But the number of fully functional carbon capture plants and their capacity is nowhere near the amount required to curb the effects of global warming.

India is one of the few developing countries to recognize the importance of CCS technology for energy security. Despite the global trend of opting for renewable energy sources, India is still dependent on fossil fuels to a great extent for energy - 80% of the energy demand is met by coal alone. In 2007, The Indian CO2 Sequestration Applied Research (ICOSAR) Network was established by the Department of Science and Technology (DST), Government of India. India demonstrated a carbon dioxide capture and storage project in the Second National Communications united Nations Framework Convention on Climate Change. Conference of Parties (CoP21) Mission Innovation was another landmark for research and development in India's carbon capture technologies. As part of Mission Innovation, India and 24 other countries are working towards delivering innovative technologies for efficient carbon capture and storage. National Aluminum Company (NALCO), Oil and Natural Gas Corporation (ONGC), Bharat Heavy Electrical Ltd. (BHEL), and Andhra Pradesh Power Generation Corporation (APGENCO) is working towards setting up CCS plants in India. National Thermal Power Corporation Limited (NTPC) has tested a pilot plant to capture and store carbon. Furthermore, private companies like TATAs have started implementing CCS technologies now. Today Tata Steel's latest technology "HISARNA" is one such example. Though India's CO2 emissions are the third-largest in the world and India is taking steps to decrease them, the response to this technology has been quite parochial. The question is; If carbon capture technologies can help in eliminating the ubiquitous problem of global warming and climate change, then why are they not prevalent?

The benefits of carbon capture are plenty, but the challenges to this game-changing technology overpower its advantages, especially in developing countries like India. Firstly, Carbon capture and storage technologies are costly, and there is little or no return on investment. Investment in CCS technology must cover carbon capture systems, CO2 transport pipelines, and storage units - all these add up to billions of dollars. And no matter how efficient the technology is, it can never guarantee 100% zero carbon emissions. Moreover, to significantly subside global warming and climate change, we need at least 2000 plus carbon capture facilities with a capacity of removing 5 billion metric tons of CO2 per year.

Furthermore, it has been proven that CCS is more expensive than other alternatives for reducing greenhouse gas emissions, such as switching to renewable energy sources. Secondly, CCS can be a risky option - the geological storage units are prone to leakages. Carbon leakage is common from sites because carbon injection into the underground geological rock exerts high pressure on the bedrock. These potential leakages could nullify the whole purpose of CCS, causing severe damage to the surrounding environment and delaying eliminating global warming. Concentrated CO2 leakage could harm people and livestock and lead to groundwater contamination. Furthermore, the reduction of emissions maybe not be as expected when the complete life cycle is taken into account - these include the carbon used in the manufacture of pipelines, compressors, and other chemicals used in CCS. Carbon storage in underground mines may sound like a viable option now, but it can prove to become deleterious in the long run.

Carbon capture and storage appear to be an effective solution. Still, in reality, it is giving licenses to industries to continue to use fossil fuels, thus delaying the whole process of shifting towards renewable energy sources - carbon capture and storage is a very ambitious solution but increasing the usage of renewable energy is proven to be an efficient solution. Carbon capture and storage is often misunderstood for their ability to remove carbon dioxide from the environment - it can only trap a fraction of carbon emissions from fossil fuel-based industries. Industries are growing complacent and are continuing the operation of such processes instead of replacing these with other environmentally friendly ones. Most of the captured CO2 in these plants is used in the enhanced oil recovery process - thus, using it to produce more fossil fuels defeats the whole purpose of inventing this technology in the first place.

Experience suggests that many of the CCS pilot plants have repeatedly given us false hopes and consistently underperformed. For Instance: Petro Nova carbon capture plant in the USA was shut down due to failure to achieve its target - The company had earlier promised that the plant could reduce 90% carbon emission during the plant's lifetime - after three years of working, it could only capture 7% of the nearby coal power plant's emissions. Earlier this year, the 1,500 member organizations of Climate Action Network (CAN) International released a position statement conveying that the currently proposed CCS applications are not proven sustainable climate solutions. CAN also urge all nations to completely stop depending on fossil fuels and opt for renewable energy sources instead of investing in carbon capture technologies. There is a misconception among everyone that only carbon capture is a solution to climate change, but using 100% clean sources will also help us keep the global temperature rise below 1.5C.

Now that we have seen the disadvantages of carbon capture, we can clearly see that the science and technology in carbon capture is very innovative, but the reality is very far from what is being advertised. Thus, making the whole concept of carbon capture and storage a myth? Then does this technology appear to be ineffective, uneconomical, unsafe, and will divert our attention from renewable energy? So it is worth investing such a significant amount; in this technology considering all the negative impacts? Yes, we can invest in the research and development of this technology and eliminate all the above-stated drawbacks. But, developing countries might find it cost-inefficient, as they have many complex problems to deal with, like poverty, food security, etc., and they cannot invest such a significant amount on a technology that may not be as effective as expected, even if they want to.

India is mainly dependent on coal-based power plants - these power plants are predominantly based on pulverized coal (PC) technology as it is suitable for Indian coals. The average efficiency of coal power plants in India is 34%, whereas it is 37% in the United States of America. Despite low efficiencies, these plants operate to meet the ever-growing energy demand - energy efficiency plays a crucial role in reducing greenhouse gas emissions. CO2 capture technologies can be implemented in these PC plants to selectively separate carbon dioxide, which can be compressed and transported away for storage. However, applying these carbon capture technologies in PC plants will increase the auxiliary consumption, coal use, and cost of generation. Post-combustion capture can increase 24-40% in additional energy consumption (IPCC). The power and efficiency penalty for installing CO2 capture equipment on existing plants is also relatively high, making it not a very viable solution to carbon emissions. Capturing CO2 is not the only hurdle, but searching for a place to store CO2 for a long duration is another tedious task. In India, geological exploration is mainly focused on hydrocarbon and coal resources - comprehensive assessment must be conducted to estimate potential storage sites. Moreover, the existing plants in India are not producing the expected results - discouraging India from further investing in this technology. Challenges to implementation of CCS technology in India are (including but not limited to) :
- Lack of proper research and development
- Need for proper geological survey for potential carbon storage sites
- Lack of policies and regulations
- Lack of capital - CCS technology is costly, and full-scale implementation of CCS in India requires foreign direct investment.
- Public opinion - People consider CCS a dangerous technology because of the possible leaks.

India is in a moral dilemma concerning carbon capture technologies; though India has implemented few CCS plants, unfortunately, the results were far from being efficient. Perhaps, the Government of India is skeptical about investing further in this technology; due to its own experience. Though there is an urgent need to implement these technologies in India, developing countries often tend to ignore them due to the lack of infrastructure and capital. No doubt, Carbon Capture and Storage (CCS) is a brilliant technology, but the cost and its many other disadvantages leave us in an indecisive position. Therefore, Developed countries such as the USA, European Union, UK, China, Korea, Australia, and New Zealand must take the initiatives and showcase investing inefficient research and development in introducing efficient CCS technologies. Developed countries must set examples of adequate CCS facilities and motivate developing countries. Since global warming and climate change are not region-specific problems, every country must come together to achieve the universal goal of eliminating Greenhouse Gases emissions.

Ms Yekkaluri Snehasree Reddy is a Research Intern at Indian Institute Of Sustainable Development (IISD), New Delhi.