On a country-by-country basis, that's the highest number of people without electricity, the Paris-based agency said in an e- mailed response to questions.
"Access to electricity is not only a result of economic growth but electricity access also contributes actively to economic growth," according to the report. "In this regard, reliability, and not just access, is very important to sustainable economic growth."
India's government has pledged to provide electricity nationwide by 2012, which would require an installed generation capacity of 200 gigawatts to sustain economic growth of 8 percent, the power ministry said on its website. The country had 165 gigawatts as of Aug. 31, according the Central Electricity Authority, short of the target by 35 gigawatts, or 18 percent.
The IEA estimates India will need to invest an additional $182 billion to 2030 to achieve universal access to electricity.
India's economy grew at 8.8 percent in the three months ended June, the fastest pace in 2 1/2 years. The country faced power shortages of as much as 10.7 percent during peak hours in August, the Central Electricity Authority said.