As we landed in Raipur airport in Chhattisgarh, it was immediately clear that India’s national relationship with coal is different to that of Europe and North America. One of the first images we faced as we passed through immigration to collect our luggage was an advert for coal.
Coal not only supplies over 70% of the power requirements of the nation, but also provides local employment and creates associated regional industries and communities. Coal is accepted as one the main means by which the nation will provide power to 100% of its growing population. However, this does not mean that the country is unaware of the associated environmental costs – far from it. India is accelerating its compliance with emission limits which western economies took decades to establish. But while meeting these standards, India must work with local coals containing up to 50% ash in regions of water scarcity. It is a significant challenge.
In Delhi, it was obvious that unhealthy levels of air pollution are still an issue, but the situation is much improved since I visited the mega-city back in 2019 at the beginning of this US Department of State (USDOS) Project of work. The successful movement and clean-up of local industries along with co-ordinated action to reduce traffic emissions (such as conversion of the tuktuk fleet from diesel to gas) has achieved noticeable improvements.
The remaining major cause of particulates in the air in Delhi is seasonal stubble burning in farms upwind of the city. And so, it is interesting that the new national requirement for coal-fired power plants to cofire 10% biomass with coal could be the policy that finally resolves these Delhi air quality issues.
NTPC are already proposing pelleting projects for local agricultural waste, developing a new sector that will halt the wasteful and highly polluting stubble burning practices and instead create a new stream of renewable and sustainable fuel for utilities in the region.
The project team created by ICSC were in both Raipur (29 -30 May) and Delhi (5 – 6 June) to deliver workshops on emission reduction and ash management on behalf of the USDOS. The timings of these two workshops coincided with the publication of two complementary ICSC reports in these areas. These are free to download from the project page here.
The new report by ICSC focussing on multipollutant emission reductions from the Indian coal fleet summarises the evolution of the Indian legislation and provides insight into the status of compliance. Many plants will either meet the NOx emissions already or will be able to do so with the use of low NOx burners. Only the newest of plants, for which the emission limit is much lower, will have to consider retrofitting flue gas systems such as selective catalytic and non-catalytic reduction (SCR and SNCR).
Indian utilities understand the challenges of compliance with NOx and are ready to address them. However, due to the high ash coals and the high rate of flexing, NOx control at Indian plants will require a significant amount of plant-specific tuning and new skill sets are emerging. Newer units will be required to install SCR systems, and will also have a challenge in adapting them to cope with the high dust situation. Currently, the reliance on vendor support is high.
Although only 4% of the utility fleet currently has flue gas desulphurisation (FGD) installed for SOx control, NTPC alone (the largest utility in India) has 56 GW of FGD under construction. Over 50% of Indian coal plants are either currently installing FGD or have commissioning dates confirmed. For me, the question now is whether the expertise and materials are available for such a significant amount of construction to happen within the planned timeframe – bottlenecks could be an issue.
Markets are emerging for more advanced systems, such as multipollutant control systems (covering particulates, NOx, SO2 and mercury) from companies such as GORE. Mercury remains a topic of less concern to our Indian audiences – based on the questions and discussions in the room at these events, there is still some confusion on both the importance of mercury (that is, questions on the need for any urgency in installing control systems) as well as the fate of mercury once it is captured in solid ash and gypsum by-products. Although the mercury captured in these materials is stable and safe, as shown through numerous studies run by the US Environmental Protection Agency, many Indian delegates showed concern for the potential concentration of mercury into materials which may be used in their homes and offices. The second new report by the ICSC “Ash management and use in India” addresses this issue and the results were presented at these workshops.
We have two more workshops to deliver in India as we move towards closure of this USDOS project. The final two events will take place in Nagpur on 27 – 28 July and in Chennai on 3 – 4 August. More information and registration is available here.
