Combating power plant emissions with clean technologies

Power plants, particularly coal-fired thermal plants, are a major cause of India’s rising carbon emissions. We analyse how this challenge can be effectively tackled with clean solutions that are the need of the hour.

Thermal power plants are a primary source of power generation in India, and are also a major contributing factor to air emissions. India contributes heavily to the increase of carbon emissions in the atmosphere by burning coal and fossil fuels through thermal plants. The Ministry of Environment and Forests recently notified revised emission standards in coal-fired power plants, which covers extensive reduction in particulate matter (PM), sulphur dioxide (SO2), nitrogen oxides (NOx), and mercury emissions. We take a look at how this objective can be achieved in a country like India where power generation and consumption are high and thermal plants constitute a major share of electricity generation.

Thermal plants asked to shut down due to high carbon emissions
The Central Pollution Control Board (CPCB) recently issued notices to around 14 thermal power plants to close down because of high carbon emission and lack of implementation of emission control products. Commenting on this, Mahesh Nandurkar, Chief Executive Officer & Board Member, Marsulex Environmental Technologies (MET) stated, “CPCB has given such a notice to these 14 power plants, as they have failed to comply to the emission norms within the stipulated timelines. In my opinion, this is just a right precedence being set by the CPCB. However, closing the plant is not always a solution. The TPP owners shall be encouraged to install Electrostatic Precipitators (ESP) to limit PM emission and Flue Gas Desulphurisation (FGD) to meet new emission limits for SO2. Calibrated “stick and carrot” approach will give better impetus to bring the paradigm shift in the mindsets of people and make them true “environmentally sensitive personalities”. Going forward, CPCB can think of incentivising the TPPs, who are complying to the emission norms by giving some monetary relaxations, something similar to the carbon credit mechanism.”

Measures being taken by power plants to comply with regulation norms for emissions
Power plants today are on a better footing in so far as control of emissions of particulate matter (PM) is concerned. Out of a total thermal capacity of 197 GW as of December 2017, PM non-compliant capacity was of the order of 73 GW, out of which units aggregating 66 GW have been considered for retrofitting/replacement of electrostatic precipitators. AK Saxena, Senior Director, Electricity and Fuels Division, TERI stated, “For control of SOx, the main issue is the implementation time of flue gas desulphurisation (FGD) system. Every new system from the ordering to implementation at the plant takes about 30 months. Utilities also take time to firm up their order. For control of NOx, assessment of viability and suitability of technologies for Indian coal was done in NTPC units on pilot basis. Revision of norms for units commissioned after 31st December 2013 was also under discussion in view of practical difficulties.”

Utilities and power plants also had a few important concerns or they were looking for clarity in regards to a few important issues. Difficulty in maintaining supply during shutdown of units, revenue loss to the utility, technology, regulatory certainty in regards to treatment of additional capital expenditure in tariff, implications on generation cost, etc. were the key concerns. One of the issues that thermal power stations have had is that due to implementation of ECS, their power becomes costly on account of increase in fixed costs as well as variable cost and they become lower in the merit order scheduling.

He added, “In so far as the power stations that are regulated by the Central Electricity Regulatory Commission (CERC) are concerned, CERC first gave inprinciple approval that the new environmental norms will be treated as change in law, and that the expenditure incurred by power plants to comply to new norms will be considered for determination tariff on a case-tocase basis. Thereafter, when the CERC came with the new multi-year tariff regulations for the period 2019 to 2024, they made an explicit provision for treatment of emission control system (ECS) in the regulations. CERC has made a provision in the regulations that tariff for the emission control systems will be determined as supplementary tariff. CERC has recently proposed certain amendments in provisions of the aforesaid tariff regulations which bring further clarity in the matter.”

The regulatory treatment at the central level has over the years been spelt out progressively and regulatory uncertainty can be said to have been addressed sufficiently. The state commissions also need to take actions so that the state power utilities as well as the investors have comfort and confidence to proceed with the implementation of the new emission control systems.

Juha Suomi, Area Director, Asia, Fortum eNext tells us, “Fortum eNext’s advanced NOx reduction technology reduces emissions effectively by staging and optimising the combustion process, thus eliminating the NOx formation at its source. Compared to alternative and expensive solutions, there is a minimum need for new equipment, with no auxiliary power consumption, no water consumption, and no ammonia or urea consumption, thus no by-products for disposal. We are also committed to make the necessary physical modifications within the scheduled shutdown of the power plant.”

Nandurkar added, “NTPC has been the torchbearer to all the TPPs in India. They have taken supremely fast actions in releasing tenders/awarding orders for most of NTPC plants over the last one year. Good news is that now there exists clarity on “how TPP will get compensated for becoming environmentally compliant, i.e., by tariff hike/pass through”. Owing to this, many of the private utilities are also at a very advanced stage of tendering/awarding contracts for ESP upgrade for PM control and FGD for SOx control. We at Marsulex Environmental Technologies, US (MET) have licensed our patented FGD technology to Thermax Ltd for India and we are happy that they have already picked up couple of FGD upgrade jobs in the last six months. Further, new NOx emission norms have been differed for implementation for now and the NOx control market will start heating up after maybe 24 to 36 months.”

Initiatives by power sector to safeguard environment
Suomi shared, “Nitrogen oxides (NOx) are one of the components polluting the atmosphere by reacting to form smog and acid rain causing adverse health effects. NOx emissions are formed as a result of natural phenomena as well as of human activity. However, the emissions caused by human activity are clearly more harmful due to high local concentration. Many consider NOx almost 10 times more harmful than carbon monoxide (CO) and a few times more harmful than sulphur dioxide (SO2).”

Over the last 30 years, the European Union has periodically tightened the air emission regulations, particularly the NOx emissions for coal-fired power plants. Suomi adds, “Fortum, being a leading clean-energy company, is offering, among other energy efficiency programmes, its own NOx reduction technology since the 1990s. The Indian government is bringing stringent laws to restrict NOx emission levels for thermal power plants to similar levels as in Europe, and there is a tremendous potential here for our offering. We have already carried out lowNOx pilot projects with NTPC at their Ramagundam plant and another one with a private power producer. Our forte is not to sell only the equipment, but to provide solutions for our customers.”

He states, “Energy consumption per capita is increasing in India, and it is envisaged that thermal will remain the mainstay in the country’s energy mix for the next 30 years. Moreover, the existing coal-fired plants will need to go through technological upgradation to meet the stringent emission norms. Even the 15-year-old to 20-year-old power plants have the potential to improve their energy efficiency and reduce their air emissions significantly, like in case of NOx emissions, by adopting the best available technologies. Through our global experience and product portfolio, we are in a good position to offer such solutions in India.”

Though non-conventional energy generation in India (primarily solar and wind) have seen a significant growth in recent years, still the backbone of energy supply to India is fossil fuel-based power and it’s not going to be any different for at least the next decade. Hence, India has a big challenge to reduce carbon emission. The policymakers are working towards “implementation of norms, compliance enforcement, penal actions, and also policy support”.

Nandurkar says, “Technology leaders like MET are working towards constantly innovating and optimising solutions to help the industry to reduce opex and capex at the same time with guaranteed “return on investment” model with our patented FGD technologies such as ammonium sulphate and potassium sulphate, to name a few. Our parent company KraftPowercon, AB has recently launched one of the world’s best ESP power supply technology “PulseKraft” which is proving to be the game changer in ESP upgrade market over conventional ESP upgrade solutions.”

Saxena added, “The new thermal power plants which have come up in the country during the last few years are by and large based on supercritical technology. The new emission norms notified by Ministry of Environment, Forest and Climate Change is the major initiative notifying graded norms for control of PM, SOx, NOx, mercury, etc. for the plants commissioned/to be commissioned. Supercritical technology having higher thermal efficiency was aimed at reduction of emissions. The plants which have to comply with the new emission norms are at various stages of bidding, award, and implementation. Progressive implementation of ECS in the plants would see reduction in emissions.”

He added, “Perform Achieve and Trade is another scheme formulated by the Bureau of Energy Efficiency, which has a provision for improvement of specific energy consumption in thermal power plants with the objective of emission reduction. The targets are being progressively improved in every cycle, which helps power plants to progressively improve their performance in terms of specific energy consumption. Nuclear plants do not produce carbon dioxide emissions or air pollution.”

Further, carbon capture utilisation and storage is a technology for mitigating CO2 emissions from coal-fired stations. However, as of now, its commercial viability is the key challenge. So, coal-fired generation which continues to remain operational in the countries that have a large coal fleet will have to be looking for employing them, subject to commercial viability or policy and regulatory support.

The existing coal-fired plants will need to go through technological upgradation to meet the stringent emission norms.
Juha Suomi, Area Director, Asia, Fortum eNext

New NOx emission norms have been differed for implementation for now and the NOx control market will start heating up after maybe 24 to 36 months.
Mahesh Nandurkar, Chief Executive Officer & Board Member, Marsulex Environmental Technologies (MET)

The new thermal power plants which have come up in the country during the last few years are by and large based on supercritical technology.
AK Saxena, Senior Director, Electricity and Fuels Division, TER