Feb 18, 2003
India adopts HVDC transmission
When the Talcher - Kolar, High Voltage Direct Current [HVDC] transmission was commissioned by Power Grid Corporation on Feb 14, the implication of the event may have been lost on many Indians.
For one, it signalled India’s arrival at the leading edge of world class, state of the art, electrical engineering technology. For another, it was a project completed nine months ahead of schedule by a public sector company. Finally,as an effective means of delivering generated power far away to places where it is needed, environmental gains are immense, as we will see.
In the second era of electricity revolution Alternating Current [AC] displaced Direct Current [DC] because its voltage can be stepped up and the lower current that results can be pumped through relatively thinner wires. At the receiving end the voltage can be stepped down to the 220 v we use. This claim for AC is still valid and used , but only over ‘shorter’ distances typical in local networks.
HVDC comes into play if very high volumes of electricity need to be transmitted over distances above 800 km. In this very advanced technology AC is converted to DC and pumped into the lines. This may seem a convoluted, complicated way. It is indeed: very few countries can today master, install and manage HVDC systems. The advantages are lower line losses, ‘slimmer’ hardware across the countryside, stable grid behaviour, dispersed generation of power, and overall economy. India’s hydel riches are in the North East, coals in the East and consumers all over the land. Pristine locations can silently generate power and need not create polluting industries nearby as consumers. HVDC ‘vacates’ massive quantum of power with ease to far away points.
India has been a pioneer developer of HVDC since 1990 when the 1000 mw Rihand - Dadri line was commissioned in UP. Since then many 500 mw lines have come up. The 2000 mw Talcher - Kolar link is the biggest so far and spans four states: Orissa, Andhra Pradesh, Tamil Nadu and Karnataka. The 5651 towers used are as high as the Kutb Minar. In all 100,00 metric tonnes of steel and 80,000 tonnes of cement were used. The project cost Rs.700 crores and was executed by Indians. As we already noted, we finished it ahead of time. These facts should give you a measure of the little-known developmental works of very high calibre that are going on in India right now. You should be justly proud of this achievement.
Greater plans are cooking. India is racing to a saturation point in electricity availability by 2012. 100,000 mw of power is planned to be added. HVDC technology will be waiting to ferry this power to all corners of India. And did you know that Mr. R V Shahi the Secretary in the Ministry of Power is not a bureaucrat but picked from the private sector?