6 August 2012
What set the stage for last week’s power outage in India, which left some 650 million people without electricity, was a widening rift between growing peak demand and the amount of generation available to meet that demand. A system had been put in place to ration the amount of power each state could draw from the national grid during peaks, but evidently those limits were simply ignored, IEEE Fellow John McDonald told National Public Radio in an interview with public radio’s much-admired program, “The TakeAway.”
McDonald, Director of Technology Strategy and Policy Development at GE Digital Energy, amplified on his remarks in a personal communication, which deserves to be quoted at length.
At 1 PM on July 31, on the eve of the blackout, loads exceeded the government-set maximums for electricity to be delivered by 7 to 132 percent in the nine states mainly affected by the outage, said McDonald. In Punjab, the excess electricity draw was 300 MW (7 percent above the maximum) in Uttar Pradesh 1600 MW (64 percent) and in Rajasthan 1100 MW (79 percent). On average, the 9 states were 28 percent above the maximum load they were allowed to draw.
According to R. Nagaraja, managing director at the Power Research & Development Consultants Pvt. Ltd., the grid discipline system depended on states’ being charged far higher rates for electricity drawn above their peak load limits. In the past that system had worked rather well, and with improvements in the nation’s grid infrastructure, operators had perhaps become somewhat complacent. But with recent shortages of water, reduced power generation, high demand for electricity and a political climate preceding elections, grid players and regulators couldn’t resist the temptation to step farther and farther over the line.
Getting back to McDonald’s insights, he says that as for the automated systems that ordinarily shed load automatically when power demand surpassed supplies, they were generally “jumpered.” “Standard procedure in advanced industrial countries is to use automatic underfrequency and undervoltage relays with multiple tiers of settings. If the system is still collapsing the SCADA/EMS would automatically (using its prioritized list of breakers) begin shedding load by opening substation circuit breakers until the system stopped collapsing.” That kind of system was supposed to be operational in India too but, presumably for the same reasons peak load limited were exceeded to recklessly, it had been deactivated.
As best one can tell, the basic cause of the Indian outage was an ostrich-like attitude by both the national government and the state governments toward the country’s fundamental electricity dilemmas. To start with McDonald’s main point, India’s peak demand has grown by 4.9 percent a year since 2006-07; with generation failing to keep pace, the peak supply deficit now exceeds 10 percent.
An aggravating factor, mentioned by McDonald and discussed at length in an earlier IEEE Spectrum post, was a shortage of water in India because of weaker-than-usual monsoons. Jigar Shah, CEO of Jigar Shah Consulting, points out in a recent Earth2Tech post that the power sector is India’s greatest single consumer of water—bigger than agriculture—and that within the power sector, almost all the water is consumed by the coal-fired power plants that produce the lion’s share of India’s electricity.
With world prices for coal rising sharply of late, India’s acute dependence on coal has turned into a problem in itself. But it also is intimately connected with a much bigger problem, the power sector’s enormous greenhouse gas emissions. That issue, discussed exhaustively in two special issues of Spectrum magazine in November and December 1999, is as intractable today as it was then.
In terms of electricity reliability, Indian citizens and Indian businesses have learned to protect themselves with backup generation (as described in our November 1999 issue). Jigar Shah notes indeed that “most of India’s most important infrastructure is backed up by [expensive] diesel generators—at a cost of over US $0.45/kWh.” But that does not protect Indians from the highly adverse health effects of burning coal and biomass, the source of pollutants that kill hundreds of thousands each year. And it leaves them exposed to the worsening global climate, which may represent another long-term threat to their water supplies.
All in all, as Churchill once said of the Soviet Union, India’s power conundrum is a riddle wrapped in a mystery inside an enigma. In the final analysis, the reason for India’s ostrich-like attitude toward its energy problems is that nobody really knows of a viable way to solve them, near-term.