Power Plant Operations
The 100MW power plant of MALCO at Mettur Dam (Tamil Nadu) is one of the largest merchant power plant in the State of Tamil Nadu. Situated about 50 Kms away from the bustling city of Salem, this coal based thermal power plant is built alongside the beautiful Stanley reservoir of the Mettur Dam.
Commissioned in 1999, the plant was initially configured with three units each of 25 MW. Encouraged by the sustained operational excellence, MALCO commissioned its fourth unit (25MW) in 2009. Currently MALCO generates 100MW from its four units of power plant.
The Power Making Process:
The major input materials for a coal based power plant are coal and water. Continuous make-up water is added to the water system after passing through pre-treatment plant and and removal of the salts in a water demineralising (DM) plant. Coal is conveyed from underground hoppers to coal bunkers located inside the boiler house through four set of conveyers by passing through magnetic separators to remove iron pieces & through crusher unit to crush coal under 20mm size. From coal bunkers coal is fed to grinding unit through coal feeders.
In fossil fueled power plants, water is taken to the boiler or steam generator where coal is burnt. The boiler transfers heat energy to the water in form of latent heat of vaporization by the chemical reaction of burning coal. Boiler system is further classified into four subdivisions namely fuel circuit, Air circuit & Steam circuit & Ash circuit.
The Super heated steam from the boilers is sent to turbines where steam is allowed to expand & convert the available heat energy in to mechanical energy. Steam turbine uses the dynamic pressure generated by expanding steam to turn its blades. The power so produced by the electric generator which is coupled with the turning steam turbine is taken to the switchyard.
Electrical Switch Gear Section:
This section comprises of Generators, Transformers and switch yard. The Generators convert the mechanical energy to electrical energy. The Switchyard distributes the power and provides the link to electricity board Grid to enable import or export of power.
MALCO’s power plant has a total of 4 units (each of 25 MW) in operation. It is a thermal power plant with primary fuel as coal. Our boiler is designed for High GCV, low ash and low sulphur coal. Our annual requirement is ~600,000 MT. Since our power plants largely uses imported coal from Indonesia, we secure our coal requirements through long-term contracts.
We have all our shipments arriving to Karaikkal which is logistically viable in terms of cost incurred and when compared to other ports like Chennai and Tuticorin. Entire movement is made by Rail.
A culture of operational excellence is reflected in MALCO’s new business model. We are supporting power requirement of Tamilnadu for last 3 years, by exporting reliable and uninterrupted power through short term power purchase agreements. We are the first in the state of Tamil Nadu to commence the power sales to third party customers, including prominent industries, at competitive rates. Third party customers benefit by getting hassle free uninterrupted power round the clock. We are embarking on a number of PLF enhancing initiatives and entering into long term contracts with third party customers.
We have been selling the complete fly ash and bottom ash generated by our power plant to brick and cement making units, thereby reinforcing MALCO’s thrust on environment protection. We are also selling red mud, which is waste product generated during the manufacturing of aluminum, to various cement companies.