In 2015, with a carbon emission share of about 7% India was the 3rd largest carbon dioxide (CO2) emitter behind China (27%) and the USA (16%). Further, carbon emission is complicated with coal burning in Jharia coal field in the eastern India.
Coal is the dirtiest of all the fossil fuels. It is a well-known fact that burning of coal, be it for any use, produces CO2, sulphurous oxides, nitrous oxides, and sooty particulate matter. These emissions, unfortunately, have detrimental effects on environment. To tackle emission of greenhouse gases, governments all over the world have started moving towards less polluting sources of energy, with huge emphasis on renewable resources like solar, wind, hydro and nuclear energy.
New Delhi is equally concerned and committed towards green energy for future growth. It has taken various initiatives, like promotion of solar power projects, setting up of biogas/mass and cogeneration plants, investing in onshore and offshore wind installations. Further, government with serious intent is pursuing repowering of old wind mills and objectively pushing development of offshore wind developments. In line with India’s INDC declaration, dependence on renewable sources of energy is bound to grow in the near future. Government’s target of achieving 175 GW of grid connected renewable energy by 2022 from current base of 45 GW, which looks a distant dream but not beyond reach.
All said and done, India’s dependency on coal, especially for power generation remains as a big concern for environmentalist and policy makers. Dependency on coal is likely to come down marginally because efficiency of renewable technology is much lower than coal based power plants. Therefore, it is reasonable to accept dependency on coal would continue for at least a decade or more. Under the emerging scenario, India needs to find a middle ground to address its energy security and meeting INDC target of cutting 30-33% carbon emission by 2030.
India is pursuing multipronged strategies revolving around green energy and diversified energy mix to address energy security. One of the feasible options is clean coal technology (CCT), which largely addresses mitigation of emission. Some of the CCT based methods deployed are coal washing, wet scrubbers, or flue gas desulfurization systems, electrostatic precipitators, low-NOx (nitrogen oxide) burners, and integrated gasification combined cycle (IGCC) systems. Gasification is a process that avoids burning coal altogether offers efficiency in the range of 40-60%.
India began its pursuit of R&D on Coal Beneficiation, Coal Gasification, Liquefaction, and IGCC in the early 1980s. Further, constant efforts are being made for introduction, adaptation, and development of clean coal technologies through policies and programmes in the country. A dedicated government chapter for further research and development has been set up, called the National Clean Coal Technology Centre (NCCTC).
Considering shortage of domestic petroleum and natural gas supply in India, dependency on coal in the immediate future is understandable. Therefore, in the last decade special focus was put on supercritical power plants. These plants offer higher efficiency and lower carbon emissions because they generate lesser carbon for the same amount of coal burnt.
The government has gone as far as saying that all new coal power plants will be making use of clean technology. It is estimated that about 100 GW of clean coal based power installation would be added by 2025. Shri Piyush Goyal, Union Minister of State (IC) for Power, Coal and New & Renewable Energy strongly supports clean coal technologies, therefore with all probability clean coal initiatives would be successful.
Despite clean coal technology offering benefits like low coal consumption, higher efficiency, and lower greenhouse gas emissions; there are not many takers.
The advancement of CCTs is facing several barriers in the forms of (i) high cost involved to support development of CCT to proving stage, (ii) amenability of advanced technologies to available coal with high ash content, (iii) inadequate R&D infrastructure in academic institutions and national laboratories, (iv) lack of academic–industry interaction for new coal-based technology, (v) constraints in development of coal blocks in the absence of adequate equipment infrastructure (vi) lack of sufficient coal evacuation facilities, and (vii) financing clean coal technologies.
In India, almost 40% of the available coal resources are deep seated (beyond 300 meters depth) which could be ideal for underground coal gasification. This is another clean coal technology that could be harnessed effectively.
As a result of increasing concerns for global warming, prospects of CCTs are becoming far more realistic. Clean coal technology can help addressing both the local as well the global environment concerns. It may take some time to establish the economic competitiveness of the technology, but the costs are definitely coming down. A long-term clean coal policy to address issues of installation of thermal power plants based on CCTs, R&D, and transfer of technology is the need of hour. Most CCTs are research intensive and are still evolving, therefore, joint research ventures should be considered for technology transfer. In super-critical and ultra-super-critical coal fired plants, much higher efficiency can be achieved. The super-critical technology is already under development in India. These facilities and technology need to be worked upon to pave way for ultra-critical technologies.
With the given current scenario, even environmentalists agree that coal is a necessary evil. India needs to push the renewable energy sector aggressively, but in the meanwhile, CCTs are the way to go. Presently, nearly two-thirds of India's power comes from coal and only a tenth of it is generated from clean coal. The government has targeted that the share of clean coal will go up to 24 per cent by 2022.
To be frank, coal, in its true sense, wouldn’t ever be clean—but it could be used in a cleaner manner than it is today. And we, the humble residents of the planet, would be much better off with the help of the clean coal technology.
(*)Ms. Harsha, Department of Management Studies, Rajiv Gandhi Institute of Petroleum Technology, India