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Key challenges for thermal power

Key challenges for thermal power
Electricity is central to India’s developmental efforts, yet a quarter of our population lives without access to it. Our per capita consumption of electricity is also considerably low, at almost a third of the world average with millions getting power a few hours a day. Surprisingly, the plant load factor (PLF) for power plants has steadily declined over the last two years and was only 63.60 percent in September 2015. PLF is the ratio between the actual energy generated by the plant to the maximum possible energy that can be generated by the plant working at its rated power capacity for a given duration.

The reason behind the low PLF could be that there has been a sharper increase in total capacity as compared to the growth in demand. Coal shortages and grid problems are also responsible. But a more fundamental problem is the dysfunctional nature of distribution companies (DISCOMS)—inefficiently run with huge losses, they don’t have the money to buy power and supply it to people. 

Meanwhile, huge generating capacity lies idle. This also exacerbates pollution problem—DISCOMS prefer buying from the older, more polluting power plants because their electricity is cheaper than that generated by the new plants. This happens because the old plants are fully depreciated and, as a result, their input cost is lower.

Roadmap for old plants: While the introduction of standards for new plants is a welcome move, more work is needed to address impacts of the existing old power plants. Old plants accounted for the bulk of the environmental impacts in the Centre for Science and Environment (CSE) study. Without stricter requirements on old plants, there will be little incentive to invest in improved technologies. In a recent departure from its policy to retire relatively small capacity (around 4 GW of capacity in the 13th Five Year Plan period), the government announced it plans to retire 36 GW of old coal-fired units. The new announcement if implemented should lead to improvements in overall efficiency.

Enforcing ambitious timelines
In the past, the power sector has fallen well short of its ambitious targets. In the last several plan periods, coal-based power capacity expansion was well below the targets. In the 12th Five Year Plan (2012-17), for example, only 2.7 GW of old plants have so far been refurbished as opposed to the target of 29 GW.

The new norms would require installing cooling towers at numerous plants; SO2 control would require installing flue-gas desulfurisations within two years. Regulators would need to establish clear milestones and ensure close supervision to ensure implementation of these rules.

Emissions data monitoring
One of the key findings of CSE’s study was widespread under-reporting of emissions. Most plants reported compliance to air pollution norms on paper while flagrantly flouting pollution norms. With further tightening of norms, it is critical that the framework for monitoring and reporting of pollution data also be overhauled.

While the continuous monitoring of ambient air quality data has become common, monitoring of stack emissions (include NOx, N2O, CO, CO2, O2, SO2 and CxHy emissions) remains a manual practice. The continuous emissions monitoring system (CEMS) can be instrumental in improving governance of pollution performance. 

The US and Europe have been extensively using CEMS for monitoring stack emissions while China has adopted the technology for SO2 monitoring and trading. In India, however, CEMS is at a nascent stage. In April 2015, Ministry of Environment, Forest and Climate Change (MOEF&CC) issued a draft notification for installation of CEMS and its monitoring and reporting protocol, but detailed framework and guidelines are yet to be established. Like in manual reporting, CEMS is also afflicted with problems of data manipulation and would need robust protocols and standards to ensure the sanctity of data.

Fly ash and market economics
The proposed notification on fly ash use is a step forward, but gaps remain that will continue to inhibit use. Currently, cement sector is the dominant user of fly ash. While the norms will improve the supply of fly ash to end-users it is not doing enough to create demand for fly ash products like bricks or push road making. Policies of different government departments, regulators and construction agencies on the use of fly ash for construction are not consistent. For instance, building bye-laws of municipalities, which set rules on the use of construction material, don’t compulsorily require fly ash bricks for construction.

Overall, the proposed and new regulations are an important first step. Coal-based power is artificially cheap because of two reasons—coal for generating power is subsidised and the health and environment costs of coal are not incorporated. The new regulations would result in a small step to add some of the costs by pushing investment in pollution control technology. It will also have the added benefit of somewhat leveling the playing field for renewables and making them competitive sooner. Given that fly ash, generation is going to increase rapidly in the future, it is imperative that its productive use is successfully popularized.

Energy consumption
Power plants consumed 530 million tonnes of coal in 2014-15, which is around 75 percent of the total coal used in the country. India’s coal is of poor quality with almost 40 percent ash, which means the plants burn 0.74 Kg/KWh of power generation, which is 41 percent higher than the global average. Poor coal also means more pollution. As a result, coal- based power plants are a significant contributor to total pollutants such as PM, NOX and SO2 in the country.

Domestic power plants were also found to be inefficient in using fresh water. Their average fresh water consumption is around twice that of the US and Chinese plants. Thermal power sector cumulatively withdraws around 22 billion cubic metres (BCM) annually, a significant usage considering that the country’s total domestic needs are estimated at 43 BCM.

Given the pace of growth of coal-based power generation (capacity is expected to reach 260 GW by 2022, up from 170 GW as of September 2015) pollution will worsen if emission regulations are left unchanged. 

(The author is programme Director – Green Rating Project (CSE). The views expressed are strictly personal.)
Priyavrat Bhati

Priyavrat Bhati

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