Leveraging aluminium for the power system overhaul in India
20 April 2017 by Special India Correspondent
India’s power demand is burgeoning and so also, is the need to reinforce the country’s transmission and distribution apparatus. As the federal government works tirelessly towards realising its dream of ‘Power for All’ by 2019, the challenges down the road, especially the ones concerning efficiency, need to be carefully taken into considersation.
By the end of February 2017, the total installed capacity of power stations in India was a staggering 315,426.32 Mw. Over the next 4-5 years, the Indian power sector will have an investment potential of $225 billion, thus throwing up immense opportunities in power generation, distribution, transmission and equipment. The government’s immediate goal is to generate two trillion units of energy by 2019 – this suggests doubling the current production capacity to provide 24×7 electricity for residential, commercial, industrial and agriculture use.
The government also plans formation of a national grid for power transmission along with the strengthening of regional and state grids. This is expected to cut transmission losses and enabling electricity for all homes. The bets on efficiency are huge. And, to attain a high level of efficiency in the power sector, the country needs to concentrate on quality, size and sound construction practices.
The transition can be led by three A’s: all aluminium alloy conductors, aluminium conductor steel reinforced, and aluminium alloy conductors for special applications. To achieve this goal, power lines need to be designed to meet the growing requirements for at least 40 years. The use of efficient conductors, fittings, and transformers with aluminium as the core material, is of paramount importance this calls for investments in developing special alloys that promise efficiency and savings. Aluminium conductors need to be manufactured out of high quality grade aluminium to ensure excellent power conduction. This facet is contextually important since all power efficient countries use aluminium of minimum 99.7 per cent purity and alloy it with necessary alloying elements to produce conductor grade aluminium.
Special aluminium alloys can help curb high AT&C losses
India suffers from steep aggregate technical & commercial (AT&C) losses that are a major drag on its power system efficiency. AT&C losses in the country still reign at the level of 35 per cent, compared to international norms of 5-9 per cent. Each one per cent loss translates into a financial burden of Rs 4000 crore for the country’s electricity distribution companies. Furthermore, it is shocking to note that the aggregate power loss in the country is almost three times the amount of power deficit. In almost half of India’s states, the AT&C losses have been going consistently over 30 per cent over the past several years. Technical losses are made up by the overloading of existing lines and sub-stations, high amounts of current flows in the system, poor repair and maintenance of equipment, and non-installation of sufficient capacitors or reactive power equipment. Then, there are commercial losses like low metering, billing & collection efficiency, pilferage of electricity & tampering of meters, low accountability of employees and absence of energy & auditing. A remedy to cut these losses lies in the applications of aluminium conductors steel reinforced (ACSR) conductors which can be operated at temperatures of up to 100 degree Celsius without any significant change in the conductor’s physical properties. The increased thermal expansion of the conductor causes power lines to reduce the clearance between the ground and the energized conductors. In view of the stringent environmental restrictions and high cost involved in constructing new lines, methods need to be explored to increase their capacity in the existing towers.
India should look at expanding the use of aluminium in electricity distribution as the metal’s low densities coupled with its excellent electrical conductivity make it a crucial material in this segment. Be it high tension wires or conductors, aluminium holds the hope of kicking out copper in such applications due to its lightweight character.
Focus on R&D for Next Gen aluminium alloy conductors
What the Indian power sector desperately needs is indigenously developed newer aluminium alloy conductors that can transfer a larger quantum of power and withstand higher operating temperatures. Here, the research strategy can be centred on exploring and developing high temperature alloy conductors with 200 degree Celsius as the normal operating temperature. India is still looking to other countries to source such high strength aluminium alloys achieved by solution treatment and ageing heat treatment. The success of production of high strength aluminium alloys is possible only when suitable technology is understood and introduced. As product development is a dynamic initiative that today’s manufacturers must seek to leverage with its worldwide network, informed decisions favour the use of better alloys with improved properties. Whilst scientists and engineers in the developed countries are investing their resources in developing the next generation aluminium alloys, not much emphasis is being given to this in India. It is clear that the focus should be on developing indigenous R&D capabilities for producing special grade alloys with a potential to change the power infrastructure landscape of the country. Some work in this direction has been started by the Jawaharlal Nehru Aluminium Research Development and Design Centre, Nagpur in the western state of Maharashtra. The centre is involved in the development of a super thermal aluminium conductor for the Indian power sector. This emerging area can be monetised as it offers an array of market applications- long distance power lines, aerials, satellite dishes & standard base for bulbs, thermal resistant aluminium with fibre reinforced metal/matrix composites as core, thermal grade aluminium with improved electrical conductivity and alumina fibre reinforced aluminium metal matrix composite and carbon fibre reinforced polymer resin composite wires.