Powerful growth of higher capacity units
S. Kishore Babu, Chairman and Managing Director, Power Mech Projects Ltd., documents how the higher capacity units are becoming eminent, day by day
India has an installed power-generation capacity of over 2,00,000 MW, out of which coal-based power plants constitute the major chunk. Most of the plants have been installed post independence, to be precious, in the last two decades. The Neyveli Lignite Corporation in collaboration with the then Soviet Union commissioned India’s first pit-head power plant in 1962. It was also South Asia’s first lignite-fired power plant.
In 1969-70, BHEL in collaboration with SKODA, ventured their first 60-W plant at Ennore Thermal Power Project in the coastal village off Chennai, Tamil Nadu. The construction of power plants gained momentum in the 8th Five-Year Plan, and the last four Five-Year Plans have contributed to the national grids against all odds. India had an installed capacity of mere 1,362 MW at the time of independence and today, it has multiplied by 150 times! BHEL almost single-handedly met the requirements of the state electricity boards until the entry of private players and NTPC, DVC etc. Even today the contribution of BHEL remains significant and praiseworthy.
After the arrival of NTPC in the 70s, establishing power plants got momentum. In the next 20 years, many power plants sprang up through the breadth and length of the Indian soil. NTPC brought significant changes in power scenario with increased plant load factor (PLF). The average PLF of India has leapt from 52.4 per cent in 1985-86 to 75.1 per cent in 2010-11.
Initially, 60 MW and 110 MW units were considered and later 210 MW units were introduced which had actually revolutionised the power industry. For almost two decades, 210 MW units were ruling the roost and prevailing over. In fact, there was more number of 210 MW units in India than all other units put together. Trombay power plant introduced India’s first 500 MW units and then this trend started increasing. The commissioning of 500 MW unit, especially in pit-heads, increased the efficiency of the plant and also the generation. It has also significantly brought down the cost of plant per MW.
The liberalisation in the last decade of the 20th century brought the private utilities in power sector. It came as opening of flush gates to the independent power plants (IPP). Even some 300, 500 and 600MW units were already commissioned. After the entry of private power utility companies, units of different capacities and makes have come up. Today there are as many brands and sizes as there are plants in India. Today power majors prefer 500, 600, 660 and 800 MW units for their plants and the ETC players are equally equipping themselves to modernise their infrastructures and facilities. The supercritical technology opened a new era, increased efficiency and higher capacities. It is also more environment friendly. India has touched 800-MW capacity units and bringing more such units in future. Higher capacity units are increasing over the years.
The multiplicity in types and sizes of TG set poses a question on the strategy for spares. Different sizes and makes mean increased inventory for the nation. Every utility should keep the minimum stock for years and then the waiting period would remain in suspense. This investment may not find its return in certain cases and late in others. The time has come to think it differently:
To develop a consortium, the member power utility partners should have a pool of essential, critical, yet non-moving spares. This consortium may have stock of spares for nonmoving items such as turbine rotors, generator vital parts, etc. They can be spared on the first-come-first-served basis and replenish thereafter. This will reduce the inventory for the nation and the saved money can be diverted for setting-up further plants. The public sector can take a lead and play an important role. Power utilities can consult among them and decide to minimise the variations in sizes and brands, so that the quantity of spares to be stored in the pool reduces. The capacity of the units may also be chosen between minimum options. The idea is that the required spares by multiple utilities should be usable.
Capacity in MW
500 MW units
600 MW units
660 MW units
800 MW units
As the number of plants is being added to the grids, the demand for operators and maintenance engineers also increases. The industry is already lacking trained engineers. The entry of units with subcritical and supercritical technologies raises the need for new engineers as well as need to update the existing engineers. We have few training centres with simulator facility across India, but they are not enough in number. Apart from modernising them, we need more such centres with modern simulators for training the engineers in subcritical and supercritical units. The proposed consortium of power majors can contemplate in setting up regional centres across India to meet the ever-growing needs of power engineers.
The industry is now facing shortage of coal, and it is affecting every plant across the country. The utility factor for several plants does not even cross 40 per cent. The country will come out of this ‘catch 22’ situation soon and go full stream in optimising the use.
As the capacity addition in the next Five-Year Plan is bound to increase multifold, we are in the right time to take a decision. This is a thought whose time has come!