Vallur Conventional, India

Tamil Nadu Energy Company is building a 1,000MW thermal power plant at Vallur in Tiruvallur district, India. Tamil Nadu Energy Board (TNEB) will have an equal stake in the project with NTPC (formerly known as the National Thermal Power Corporation). The project, projected to cost Rs 5,400 crore (€100m), is scheduled for completion by 2012, with the capacity in future likely to be increased to 1,500MW.

Coal for the plant will be brought from Orissa through ship to Ennore port, from where it will be transported by road. The plant will consume 4.62 million tonnes of coal a year. Set up under the mega power project policy, it will add nearly 24 million units a day to the grid. Of the 1,000MW generated, Tamil Nadu will take 750MW and the rest will go to Karnataka, Kerala and Puducherry.

BHEL TO SUPPLY VALLUR UNITS

India's Bharat Heavy Electricals Ltd won the INR 1,990 crore contract to supply units for Vallur. The state-run power equipments maker will supply and install steam generator and steam turbine packages – two 500MW units. BHEL's work involves design, engineering manufacture, supply, erection and commissioning of the steam generators, turbine generators, electrostatic precipitators and associated auxiliaries, and controls and instrumentation systems.

The company produces boilers for power generation with ratings upwards of 30MW. For higher capacities, it offers the option of Once-Through type steam generators as well as conventional natural and controlled circulation types. BHEL steam generators feature tangential/wall and direct/indirect firing.

Systems can be single- or two-pass type, with front/rear/side mill layout. They can have single/bi-drum arrangement with natural or controlled circulation. There is constant or sliding pressure operation, and hot or cold primary air systems.

Steam turbine speeds are 3,000rpm. The main steam is at 130–250bar at 500–540°C. Steam reheat is at 30–70 and 500–600°C. The back pressure is between 20 and 300mbar.

FLURRY OF INDIAN JOINT VENTURES

As one of the most industrialised of India's states, Tamil Nadu has many manufacturing companies in and around Chennai. It has a mix of nuclear, hydroelectric, wind power and thermal plants, and sells any surplus power to the neighbouring states of Andra Pradesh and Karnataka.

BHEL outbid leading European equipment suppliers, Czech Republic-based Skoda and Italy-based Ansaldo, for the contract. BHEL recently also won three contracts for supplying and installing seven 500MW sets at Jhajjar sewerage treatment plants, Koderma thermal power station (TPS) and Durgapur Steel TPS.

BHEL is one of India's nine largest public sector undertakings (PSUs) and the largest thermal power generating company in India. The Government of India holds the majority of equity shares. So far, BHEL has won orders for the supply and installation of 60 500MW units, of which 31 have been commissioned. BHEL plans to enhance its manufacturing capacity in the next three years, from the current level of 6,000MW to 15,000MW a year.

Another joint venture project, a 1,000MW plant at Tuticorin, recently received environmental clearance. One 500MW additional unit each at the North Chennai thermal power station Ennore and the Mettur thermal power station have been proposed, along with a 500MW pumped storage hydro electric project at Kundah in the Nilgiris.

Bids have been floated for the North Chennai unit, and environmental and forest clearances are expected for the other two projects shortly. The capacity of all the projects is 4,500MW. With an investment of Rs. 6 crore per MW (including transmission and distribution costs), the total cost will be around Rs. 26,000 crore.

Tamil Nadu Energy Company is a joint venture company floated by the NTPC and Tamil Nadu Electricity Board. From an installed capacity of only 156MW with annual gross generation plus purchase of 630MU (million units) at independence, the TNEB has grown to producing over 10GW now. That includes 2,970MW from four thermal stations, 424MW from four gas turbine stations, 19MW from wind turbines, and 2,184MW from 37 hydro stations.

There is also 1,154MW coming from private sector projects, 2,859MW as Tamil Nadu's share from central generating stations, 335MW as external assistance and 175MW from captive power plants. The generating capacity from privately owned wind farms is 3.5GW.