In 2015 the Indian Government set challenging new emission limits, or "norms", for particulate, SO2 and NOx emissions from coal-fired utilities. These limits will require control technologies to be installed on most units and could be particularly challenging considering the high ash content of Indian coals. (NOx control for high ash coals is covered in a new draft report from the IEA Clean Coal Centre.) The compliance date for plants to install control technologies to reduce emissions to below the new limits is the end of 2019. Whilst it is generally accepted that a significant number of plants will not be able to retrofit control technologies within this time frame, there does seem to be a move towards compliance in the longer term. India is simultaneously proposing a 25 year lifetime limit on existing sub-critical plants, to be replaced by super-critical units as they pass this age. This would mean that some plants will simply close rather than retrofit controls. However, again the practicality of this has been questioned considering the large number of plants involved and the high cost of new plant build.
The first ever technical guidance manual for emissions monitoring in India
Those issues aside, one of the major, often overlooked, issues for India is that most plants are not fitted with continuous emissions monitoring systems (CEMs). Further, few, if any, plants have carried out regular checks on emissions of SO2 and NOx as, up until now, the emission concentrations of these pollutants have been controlled by stack height rather by emissions control. And so the country is setting emission limits and moving swiftly towards emissions control with very few actual data on the current emission levels. Whilst emissions can be estimated based on emission factors and activity data, the high ash content and variability in quality of Indian coals make it difficult to produce an accurate baseline emission estimate for each plant. It is therefore imperative that plants start to monitor their emissions, not only to inform the baseline and provide a measure for policing compliance, but also to help determine what control technologies will be best suited to reach the new norm limits.
During previous visits to India by our staff, it became clear that, although some utilities were beginning to buy and install continuous emissions monitoring systems, they were doing so without there being any national standards or guidance on how to do so. At the moment, India does not have facilities for CEM certification or even for calibration of such systems. And so, until this issue is sorted, the data coming from monitoring programmes in India will be subject to speculation on their accuracy.
In response to this huge challenge, we helped bring the Conference on Emissions Monitoring
, a conference which takes place every two years and which was established by the IEA Clean Coal Centre in 2009, to New Delhi in September 2017. Over 350 delegates attended and received advice and guidance on emissions monitoring systems and techniques. Prior to this, we networked the Centre for Science and the Environment, a large NGO based in New Delhi, with the Source Testing Association of the UK. These two organisations have now worked together to produce the first ever technical guidance manual for emissions monitoring in India. This is a huge step forward - emissions can't be effectively controlled if they cannot be effectively measured.
The new manual (available to buy here
) is based largely on EU methods and is an excellent overview of monitoring systems for large combustion plants.