The railways witnessed an unprecedented disruption of services on Monday, following the Northern Grid’s failure. Since the railways generate no captive power, around 400 passenger trains and 250 freight trains were hit. Services are expected to become normal only by Wednesday morning.
All trains on trunk routes were delayed by six to eight hours. Besides, ripple effects were also felt elsewhere. “With diesel engines being the only back-up, the option of using those was not there, as redirecting those from other zones were required. The option of opening other routes was also ruled out, as the whole network was electrified,” said an official.
Even the resumption of rail services was very patchy, as the power supply was intermittent and tripped at regular intervals, the official added.
What made the situation peculiar was that there were five trunk routes which have inward or outward traffic from Delhi — Delhi-Mumbai, Delhi-Chennai, Delhi-Howrah, Delhi-Haryana, Delhi-Ambala. The impact of the grid failure was felt on around 2,000 km of rail routes. The signals were also down, and, hence, there was an attempt to halt the trains at stations and not at the block sections, the official said.
To optimise operating expenditure and reduce its dependence on the main power supply, the railways is setting up its own captive power plants. The first such coal-based thermal power plant is being set up at Nabhinagar in Bihar, in a joint venture with NTPC. Since the current peak requirement of the railways is about 4,000Mw, two more captive plants of 1,320 Mw at Adra (coal-based) and 700 Mw at Thakurli (gas-based) have been planned.
Indian Railways consumed over 16.65 billion units during 2011-12, and paid an electricity bill of about Rs 8,700 crore for traction and non-traction usage.
Airports sail through power supply disruption
Airports across north India were virtually unaffected by the major power supply breakdown that saw the railways’ operations in the region almost coming to a standstill on Monday.
As soon as the power supply showed fluctuations in the early morning, the main receiving sub-station at the Indira Gandhi International Airport ensured the diesel generator (DG) sets automatically took the load. The emergency DG sets were designed to take much more than the assigned load to ensure passenger and air traffic movement were not hit, said a Delhi International Airport Limited statement. “During the entire period of failure of power supply in the Northern Grid from 2:33 am, flight operations at IGIA were absolutely normal. There were no cancellations or delays. The entire load of the airport was restored in 15-60 seconds,” it added.
In the northern zone, medium-sized airports such as those at Amritsar, Chandigarh, Jaipur, Varanasi and Lucknow have 2,000-5,000 kilo volt ampere (kva) power transformers. Delhi is the only airport in the region that has transformers of more than 10,000 kva.
All airports in India are equipped with DG sets for power back-up. Capacities of these sets in medium- and small-sized airports range from 250 kva to 1,000 kva. A 250-kva DG set consumes 30-40 litres of diesel per hour, 1,000-kva sets need 80 to 95 litres per hour and 3,000-kva sets use about 200 litres an hour. The cost of using these DG sets was about two to three times that of using conventional services, said a government official.
“All airports have about 72 hours of fuel (diesel) availability for each DG set in the power house. And, in case airports run out of diesel, oil companies are expected to provide the fuel on a priority basis,” the official said.
Power supply to airports is classified under essential and non-essential services. All public-use areas come under essential services and the back-up for this is 100 per cent. For non-essential services, there is a selective back-up, as these do not affect customers. Under essential services, there are some critical ones directly related to operations such as runway lighting and everything related to landing and taking off of aircraft. These operations are never disrupted, as these are directly connected to uninterrupted power supply. In case this provision is utilised to its maximum capacity, the connection is shifted to a DG set. An official said very important services had back-to-back connections.
Over 60 per cent of India’s airports have power transformers of up to 1,000 kva, 25 per cent airports have 2,000-5,000 kva transformers and four per cent of the airports have 5,000-10,000 kva transformers. Five airports---Delhi, Hyderabad, Kolkata, Mumbai and Bangalore---have power transformers of capacities
