The outages on March 8 and 9 in New Delhi and several neighboring states were blamed on heavy fog and pollution that settled on transmission lines, tripping them when their insulation proved insufficient to handle the conditions, said Shailendra Dubey, chief engineer of the state-run Uttar Pradesh Power Corporation.
Dozens of trains came to a standstill or ran behind schedule, said Amrish Saxena, a railroad official in Lucknow, the capital of Uttar Pradesh state.
Federal Power Secretary Anil Razdan ordered replacement of conventional insulators with polymer insulators in transmission lines to prevent collapse of the power supply in the region, the Hindustan Times newspaper reported.
India faces regular power shortages, particularly in the hot summers when demand rises, sometimes outstripping supply by 25 percent.
Despite more than a decade of rapid economic growth, India's infrastructure still lags far behind, particularly the energy sector needed to fuel the economy, raising concerns it could slow further development.
India needs to build hundreds of new power plants over the next five years to end the massive electricity shortages that threaten the country's rapid economic growth rate.
The government has set a target of generating at least 200,000 megawatts of power by 2012. Currently, the country has a total capacity to produce 130,000 megawatts.
The power sector in the country is mostly run by state governments, which have been slow in adding new capacities because of lack of funds. Although the sector was opened to private capital more than a decade ago, few companies have invested in building new plants because of regulatory bottlenecks.
Currently, 30 to 45 percent of electricity produced in many states is lost in transmission and distribution, according to government figures.