How to reduce emissions in coal-based power plants

Inefficient coal-based power plants are the major threats for our environment. This article highlights the Indian scenario and suggests how we can reduce emissions from such plants
 Of the total pollution from the industrial sector, the coal-based power sector currently accounts for approximately 60 per cent of particulate emissions, 45-50 per cent of sulphur dioxide (SO2) emissions, 30 per cent of nitrogen oxide (NOx) emissions and more than 80 per cent of mercury emissions.
Earlier this year, CSE had released its environmental rating of the coal-based thermal power sector, under its Green Rating Project. 47 plants – adding up to 55 per cent of the nation’s capacity – were rated ‘poor’ on all the parameters.
Kyoto Protocol ‘episode’Over 100 developing countries, including China and India, were exempted from the Kyoto Protocol. So the question is: Did exemption from Kyoto Protocol backfired India in reducing the CO2 emissions?
According to Kishor Kumar Bhardwaj, Head – EHS, Hindustan Power Projects Pvt Ltd, “India and China both have ratified the Kyoto Protocol. However, India and China are in the list of developing countries. And countries in this list have no target assigned for GHGs reductions. So, I don’t think exemption to reduce GHGs emissions under Kyoto Protocol backfire India in reducing CO2 emissions.”
Sharing his comments on the same topic, Sanjeev K. Kanchan, Deputy Programme Manager, Sustainable Industrialisation-GRP, Centre for Science and Environment said, “As a developing country, India did not need to commit itself to any national emission reduction targets under the Kyoto Protocol. Per capita CO2 emission in India is 1.8 tonnes, far below of OECD (10.61 tonnes) and world average (4.39 tonnes). Even by 2031, it would remain below today’s world average. Therefore, India’s voluntary commitment to reduce the emissions intensity of its GDP by 20 – 25 per cent by 2020 (comparison to the 2005 level) is an important contribution to the global effort to mitigate climate change.”
India and adoption of advanced technologiesIndia still is lagging back when it comes to modernising thermal power plants and reduce the coal usage per unit of electricity generation (kg/kWh). Modernisation with reduction in coal usage (kg/kWh) will help in reducing the national emissions. Quality of Indian coal will remain same but with the improvement in combustion technologies, emissions can be reduced.
Compared to the CO2 emission rate in an advance power plant (ultra-super critical) at 0.67tCO2/MWh power generation, average CO2 emission by an Indian plant is nearly double. The reason is our fleet of coal–based power plant which has major proportion of smaller, outdated and inefficient plants. A less efficient plant consumes more fuel for power generation which in-turn generates more CO2. Around 95 per cent of coal-based power generation capacity in India still operates on inefficient sub-critical technology. For example, Japan started running advanced ultra-supercritical plants 15 years back, which led it to be the country with one of the highest efficient power sector, above 40 per cent efficiency, in the world plant. Even after 15 years, India doesn’t have any ultra-supercritical plant till, and therefore, the efficiency of Indian plant is one of the lowest, around 33 per cent.
Therefore, India needs to bring in the advanced power plant (ultra-super critical) to reduce the CO2 emission. Mr Kanchan thinks, “It indicates, we have the biggest opportunity to control over GHG emission through improvement in this sector. What we are supposed to do is to phase out the in-efficient plants and modernise those which have scope of improvements. Where the older plants need to improve, the new and upcoming ones need to be ensured for having efficient and clean technologies.”
Thus, if India adopts the advanced power plants, have huge scope of improvement in energy efficiency, therefore in CO2 emission reduction as well. One can imagine the scope of improvement with the fact that, if we improve the efficiency by 3.5 per cent, our CO2 emission can reduce by 9 per cent. Even if a 300 MW plant improves its efficiency by 1 per cent, it can save 1 million tonnes CO2 over its life of 25 years.
Carbon capture, use and storage Carbon capture and storage (CCS) involves capturing carbon dioxide from the flue gas of fossil power plants and long-term sequestration/storage. CCS is being considered worldwide as the key options for climate change response. Now the question arises: Is near-zero emissions from coal with carbon capture, use and storage (CCUS) possible?
According to Mr Bhardwaj, “CCS has been identified by the IPCC as one of the key technologies in global efforts to stabilise CO2 concentrations at 450 or 550 ppm. Widespread adoption of CCS has the potential of reducing fossil fuel emissions by 85 per cent or more by 2050.”
To see on the other side, capturing the emitted CO2 and storing it has been observed in some countries but not widely. And as far as use of captured CO2 is concerned, it is still in the research and development phase. Even the carbon capture and storage CCS is very costly and has significant drawbacks like uncertainty over potential storage capacity, possibilities for leakage, increased public resistance and energy costs etc. Adding to it, CCS impacts hard on energy efficiency of the plant, reduces efficiency by 7-13 percent, therefore the power generation required to compliment that much power in-turn will emit additional CO2. Mr Kanchan, said, “CCS in India is still not out from laboratory scale and there is no concrete success has made in this direction.”
Available technologies India needs high efficiency combustion technologies such as super critical and ultra-super-critical plants equipped with advance pollution control equipment. Efficient combustion technology not only reduces CO2 emission, it also helps to reduce emission of nitrogen oxides, generated during in-efficient combustion process, which has significant impact on climate change. High-end technology also allows installation of better pollution control measures.
Off late, an Advanced Ultra Super Critical Technology R&D Project has been approved by the Indian government at a cost of `1,500 crore involving BHEL, NTPC and Indira Gandhi Centre for Atomic Research (IGCAR) for enhanced efficiency of thermal generation. The objective of the scheme is to achieve higher efficiency, reduce carbon-dioxide emissions and reduce coal consumption for coal based power plants.
Regulatory pushWith the aim of tightening pollution norms for coal-based power plants in the country, the environment ministry has proposed a fresh standard for old and new units seeking them to substantially cut down release of dangerous particulate matter (PM).
India currently has no standards for SO2, NOx and mercury emissions from this sector. As the impact of pollution from coal-based power generation is known to be disproportionately high, the environment ministry proposed to tighten norms for emissions of PM, SO2, NOx and mercury and cut water use by coal-based thermal power plants.
However, there are currently no standards to curb emissions of SO2, NOx and mercury. The only standards that exist are for PM, which are quite lax compared with the global norms.
This fact was highlighted by finance minister Arun Jaitley in his budget speech in support of an additional cess of ` 100 per tonne on coal that will be used to invest in clean generation.
Proposed standardsThe new standards will be expected to cut particulate emissions from new plants by 25 per cent; SO2 emissions by 90 per cent; NOx emissions by 70 per cent and mercury emissions by 75 per cent compared with the existing state-of-the-art plants. Those plants that were established after 2003 will need to meet slightly lower standards, while plants older than 2003 will be required to meet more relaxed norms. “We believe these lower standards are acceptable given technical and economic limitations in installing pollution control equipment in older units,” said Priyavrat Bhati, CSE’s Director for Green Ratings Project._____________________________________
CCS in India is still not out from laboratory scale and there is no concrete success has made in this direction.
Sanjeev K. Kanchan, Deputy Programme Manager, Sustainable Industrialisation-GRP, Centre for Science and Environment________________________________________________
Widespread adoption of CCS has the potential of reducing fossil fuel emissions by 85 per cent or more by 2050.
Kishor Kumar Bhardwaj, Head – EHS, Hindustan Power Projects

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How to reduce emissions in coal-based power plants

Inefficient coal-based power plants are the major threats for our environment. This article highlights the Indian scenario and suggests how we can reduce emissions from such plants
 Of the total pollution from the industrial sector, the coal-based power sector currently accounts for approximately 60 per cent of particulate emissions, 45-50 per cent of sulphur dioxide (SO2) emissions, 30 per cent of nitrogen oxide (NOx) emissions and more than 80 per cent of mercury emissions.
Earlier this year, CSE had released its environmental rating of the coal-based thermal power sector, under its Green Rating Project. 47 plants – adding up to 55 per cent of the nation’s capacity – were rated ‘poor’ on all the parameters.
Kyoto Protocol ‘episode’Over 100 developing countries, including China and India, were exempted from the Kyoto Protocol. So the question is: Did exemption from Kyoto Protocol backfired India in reducing the CO2 emissions?
According to Kishor Kumar Bhardwaj, Head – EHS, Hindustan Power Projects Pvt Ltd, “India and China both have ratified the Kyoto Protocol. However, India and China are in the list of developing countries. And countries in this list have no target assigned for GHGs reductions. So, I don’t think exemption to reduce GHGs emissions under Kyoto Protocol backfire India in reducing CO2 emissions.”
Sharing his comments on the same topic, Sanjeev K. Kanchan, Deputy Programme Manager, Sustainable Industrialisation-GRP, Centre for Science and Environment said, “As a developing country, India did not need to commit itself to any national emission reduction targets under the Kyoto Protocol. Per capita CO2 emission in India is 1.8 tonnes, far below of OECD (10.61 tonnes) and world average (4.39 tonnes). Even by 2031, it would remain below today’s world average. Therefore, India’s voluntary commitment to reduce the emissions intensity of its GDP by 20 – 25 per cent by 2020 (comparison to the 2005 level) is an important contribution to the global effort to mitigate climate change.”
India and adoption of advanced technologiesIndia still is lagging back when it comes to modernising thermal power plants and reduce the coal usage per unit of electricity generation (kg/kWh). Modernisation with reduction in coal usage (kg/kWh) will help in reducing the national emissions. Quality of Indian coal will remain same but with the improvement in combustion technologies, emissions can be reduced.
Compared to the CO2 emission rate in an advance power plant (ultra-super critical) at 0.67tCO2/MWh power generation, average CO2 emission by an Indian plant is nearly double. The reason is our fleet of coal–based power plant which has major proportion of smaller, outdated and inefficient plants. A less efficient plant consumes more fuel for power generation which in-turn generates more CO2. Around 95 per cent of coal-based power generation capacity in India still operates on inefficient sub-critical technology. For example, Japan started running advanced ultra-supercritical plants 15 years back, which led it to be the country with one of the highest efficient power sector, above 40 per cent efficiency, in the world plant. Even after 15 years, India doesn’t have any ultra-supercritical plant till, and therefore, the efficiency of Indian plant is one of the lowest, around 33 per cent.
Therefore, India needs to bring in the advanced power plant (ultra-super critical) to reduce the CO2 emission. Mr Kanchan thinks, “It indicates, we have the biggest opportunity to control over GHG emission through improvement in this sector. What we are supposed to do is to phase out the in-efficient plants and modernise those which have scope of improvements. Where the older plants need to improve, the new and upcoming ones need to be ensured for having efficient and clean technologies.”
Thus, if India adopts the advanced power plants, have huge scope of improvement in energy efficiency, therefore in CO2 emission reduction as well. One can imagine the scope of improvement with the fact that, if we improve the efficiency by 3.5 per cent, our CO2 emission can reduce by 9 per cent. Even if a 300 MW plant improves its efficiency by 1 per cent, it can save 1 million tonnes CO2 over its life of 25 years.
Carbon capture, use and storage Carbon capture and storage (CCS) involves capturing carbon dioxide from the flue gas of fossil power plants and long-term sequestration/storage. CCS is being considered worldwide as the key options for climate change response. Now the question arises: Is near-zero emissions from coal with carbon capture, use and storage (CCUS) possible?
According to Mr Bhardwaj, “CCS has been identified by the IPCC as one of the key technologies in global efforts to stabilise CO2 concentrations at 450 or 550 ppm. Widespread adoption of CCS has the potential of reducing fossil fuel emissions by 85 per cent or more by 2050.”
To see on the other side, capturing the emitted CO2 and storing it has been observed in some countries but not widely. And as far as use of captured CO2 is concerned, it is still in the research and development phase. Even the carbon capture and storage CCS is very costly and has significant drawbacks like uncertainty over potential storage capacity, possibilities for leakage, increased public resistance and energy costs etc. Adding to it, CCS impacts hard on energy efficiency of the plant, reduces efficiency by 7-13 percent, therefore the power generation required to compliment that much power in-turn will emit additional CO2. Mr Kanchan, said, “CCS in India is still not out from laboratory scale and there is no concrete success has made in this direction.”
Available technologies India needs high efficiency combustion technologies such as super critical and ultra-super-critical plants equipped with advance pollution control equipment. Efficient combustion technology not only reduces CO2 emission, it also helps to reduce emission of nitrogen oxides, generated during in-efficient combustion process, which has significant impact on climate change. High-end technology also allows installation of better pollution control measures.
Off late, an Advanced Ultra Super Critical Technology R&D Project has been approved by the Indian government at a cost of `1,500 crore involving BHEL, NTPC and Indira Gandhi Centre for Atomic Research (IGCAR) for enhanced efficiency of thermal generation. The objective of the scheme is to achieve higher efficiency, reduce carbon-dioxide emissions and reduce coal consumption for coal based power plants.
Regulatory pushWith the aim of tightening pollution norms for coal-based power plants in the country, the environment ministry has proposed a fresh standard for old and new units seeking them to substantially cut down release of dangerous particulate matter (PM).
India currently has no standards for SO2, NOx and mercury emissions from this sector. As the impact of pollution from coal-based power generation is known to be disproportionately high, the environment ministry proposed to tighten norms for emissions of PM, SO2, NOx and mercury and cut water use by coal-based thermal power plants.
However, there are currently no standards to curb emissions of SO2, NOx and mercury. The only standards that exist are for PM, which are quite lax compared with the global norms.
This fact was highlighted by finance minister Arun Jaitley in his budget speech in support of an additional cess of ` 100 per tonne on coal that will be used to invest in clean generation.
Proposed standardsThe new standards will be expected to cut particulate emissions from new plants by 25 per cent; SO2 emissions by 90 per cent; NOx emissions by 70 per cent and mercury emissions by 75 per cent compared with the existing state-of-the-art plants. Those plants that were established after 2003 will need to meet slightly lower standards, while plants older than 2003 will be required to meet more relaxed norms. “We believe these lower standards are acceptable given technical and economic limitations in installing pollution control equipment in older units,” said Priyavrat Bhati, CSE’s Director for Green Ratings Project._____________________________________
CCS in India is still not out from laboratory scale and there is no concrete success has made in this direction.
Sanjeev K. Kanchan, Deputy Programme Manager, Sustainable Industrialisation-GRP, Centre for Science and Environment________________________________________________
Widespread adoption of CCS has the potential of reducing fossil fuel emissions by 85 per cent or more by 2050.
Kishor Kumar Bhardwaj, Head – EHS, Hindustan Power Projects

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