Emissions from coal-fired power plants caused up to 100,000 early deaths in India last year, a new report from Greenpeace said.

The "Coal Kills" report released by Greenpeace India says that millions of people suffer from asthma, heart disease and other health related problems related to the emissions, costing India $3 billion-$4 billion.

India, the world's second largest coal burner after China, depends on coal-fired power plants to generate about 66 percent of its still-limited power generation. The majority of capacity additions planned under the government's 12th five-year plan ending in 2017 is also coal-based.

Almost 400 million people in India don't have electricity and power outages are frequent. Last July more than half the country had no electricity because of massive blackouts.

The report, commissioned by Conservation Action Trust in partnership with Greenpeace, uses data on 111 coal-fired power plants representing 121 gigawatts of generation capacity.

Indian standards for coal power emissions are "either absent or shamefully behind" countries like the European Union or the United States and even China, Debi Goenka, founder of Conservation Action Trust, said in a statement.

Also, India has no prescribed emissions standards for key pollutants like sulfur dioxide, nitrogen oxides and mercury.

"Thousands of lives can be saved every year if India tightens its emissions standards, introduces limits for pollutants such as sulfur dioxide, nitrogen oxides and mercury and institutes mandatory monitoring of emissions at plant stacks," said report author Sarath Guttikunda, a former head of the World Bank's pollution division.

A World Health Organization study in 2011 of publicly available air quality data listed 27 cities in India among the top 100 cities with the worst air quality in the world.

The incidents of emissions-related death and disease in India isn't evenly spread because of power plant concentrations wind patterns and population density, the "Coal Kills" researchers say.

The report says that Delhi, Haryana, Maharashtra, Madhya Pradesh, Chhattisgarh and Indo-Gangetic plain suffered the most.

While India has pollution standards for ambient air quality, none exist for individual power plants, which the report says compromises monitoring and enforcement standards. Aside from coal plant stack emissions, fugitive dust from coal-handling units and ash ponds is also a concern.

As India's energy demand outpaces supply, the country's usual power outages and blackouts have become more frequent, particularly amid coal shortages.

The Indian government has said that the country would need to import 185 million tons of coal annually by 2017 to meet increasing shortfalls. By contrast, 2011 imports reached around 90 million.