What fuels a thermal power station?

• Among several systems required in a thermal power plant the key ones are a boiler, a turbine, and a generator.

Getting to know the boiler!

• A boiler, as the name suggests, is a place where water is boiled to make steam.
• It is made up of about 100 miles of pipes, all welded together for better heat flow from the fire to the water.
• A big furnace, 14 storeys high provides the required heat to the water.
• The reservoir at the top collects steam for delivery to a high pressure turbine.
• Well, after all the energy from steam is used up by the turbine, it is sent to a condenser.
• The condenser turns the leftover steam to water and a pump sends it back to the boiler.
• This completes the boiler cycle.

The turbine!

• In simple terms, a steam turbine works by using a heat source (gas, coal, nuclear, solar) to heat water to extremely high temperatures until it is converted into steam.
• The turbines are connected to a generator with an axle, which in turn produces energy via a magnetic field that produces an electric current.

• Co-generation is a concept of producing two forms of energy from one fuel.
• One of the forms of energy must always be heat and the other May be electricity or mechanical energy.
• In a conventional power plant, fuel is burnt in a boiler to generate high-pressure steam.
• This steam is used t6 drive a turbine, which in turn drives an alternator to produce electric power.
• The exhaust steam is generally condensed to water which goes back to the boiler.
• Since the low-pressure steam has a large quantum of heat which is lost in the process of condensing, the efficiency of conventional power plants is only around 35%.
• In a cogeneration plant, a very high efficiency level, in the range of 75%-90%, can be reached.
• The low-pressure exhaust steam coming out of the turbine is not condensed but used for heating purposes in factories or houses!
• Co­generation has other advantages as well, especially in the form of significant cost savings for the plant and reduction in emissions of pollutants due to reduced fuel consumption.
• Even at conservative estimates, the potential of power generation from co­generation in India is more than 20,000 MW.
• Since India produces an enormous amount of sugar, bagasse-based cogeneration is being promoted.
• The potential for co-generation is primarily in sugar and rice mills, distilleries, petrochemical sector and industries such as fertilizers, steel, chemical, cement, pulp and paper, and aluminum petrochemical sector and industries such as fertilizers, steel, chemical, cement, pulp and paper, and aluminum.

• Petroleum, an inflammable liquid composed primarily of 90 to 98 percent of hydrocarbons, the rest comprising chiefly of organic compounds.
• In India, as you know, crude oil is produced both onshore and offshore.
• The offshore production contributes nearly two-thirds of the total crude oil production in India, while the onshore production is restricted to the states of Gujarat, Assam, Nagaland, Tamil Nadu, Andhra Pradesh and Arunachal Pradesh.
• However, the demand for oil in India cannot be met by domestic production.
• As a result, the country has to import, both in the form of crude oil and oil products.
• Use of oil for power generation is indeed limited in our country.
• It is used mainly in the thermal stations close to the oil wells and refineries and maybe used in diesel and gas turbine stations.
• Natural gas is mainly available both alone and in association with crude oil.
• In India, most of the natural gas output comes from associated gas fields.
• Around 70 per cent of our current gas production comes from offshore Bombay High field and onshore fields in Gujarat
• The production from established fields is expected to reach a higher level as the demand for natural gas for power generation increases.

• As of April 2021, India has a total Thermal installed capacity of 234 GW, of which 53% of the thermal power is obtained from coal and the rest from Lignite, Diesel, and Gas.
• The private sector in the power industry in India generates 47.4% of the country’s thermal power, whereas States and the Centre generate 27.1% and 25.5%, respectively.
• Indian power sector is undergoing a significant change that has redefined the industry outlook.
• The power industry's future in India is bright, and sustained economic growth continues to drive electricity demand in India.
• The Government of India’s focus on attaining ‘Power for all’ has accelerated capacity addition in the country.
• In the earlier stages of power development, the thermal power stations consisted of several small widely scattered units.
• The first step in development of thermal power on a large scale was the establishment of power station in Bokaro.
• Bokaro later became the forerunner for the chain of thermal power stations that have developed subsequently, including large thermal stations like Neyveli, Dhuvaran, Korba, Trombay, etc.
• Large findings of coal have also made it possible to set up new projects in Singrauli, Korba, Talcher and several other places.

• Old inefficient plants continue to operate whereas more efficient plants are underutilized.
• As the gap between the average cost of supply (ACS) and average revenue realized (ARR) persists due to high aggregate technical and commercial (AT&C) losses, distribution companies (discoms) use load shedding to minimize losses.
• Although legally independent, Regulatory Commissions are unable to fully regulate discoms and fix rational tariffs.
• Unmetered power supply to agriculture provides no incentive to farmers to use electricity efficiently.
• There is a lot of hidden demand because of unreliable supply and load shedding.
• State power utilities are not able to invest in system improvements due to their poor financial health.
• High industrial/commercial tariff and the cross-subsidy regime have affected the competitiveness of the industrial and commercial sectors.

• Promote smart grid and smart meters.
• All PPAs including those with state generation companies (gencos) should be based on competitive bidding.
• Introduce a capacity market to encourage flexible capacity for peak demand and intermittency
• Privatizing state distribution utilities and/or the use of a franchisee model will reduce AT&C losses.
• Discoms may adopt a franchisee model for its retail business in rural areas and stipulate a minimum level of performance parameters, including the use of decentralized generation sources and storage systems for local reliability and resilience.
• Regulatory bodies need to be further strengthened and made truly independent.
• For agriculture, an upfront subsidy per acre of land through Direct Benefit Transfer (DBT) may be considered instead of providing separate subsidies for fertilizers, electricity, crop insurance etc.
• Promote the use of solar pumps for agriculture. Local discoms should buy surplus power from the farmer.
• Discoms may be fined for load shedding.
• Ensure effective enforcement of a cap on cross-subsidy and open access. It is also necessary to remove high open access charges. Actively promote cross-border electricity trade to utilize existing/upcoming generation assets.
• Introduce time-of-day tariff to promote the use of renewable energy.
• Introduce performance-based incentives in the tariff structure.
• To manage the demand for power, it is necessary to introduce 100 per cent metering, net metering, smart meters, and metering of electricity supplied to agriculture.