Building just a third of planned new coal-fired power plants around the world would push hundreds of millions of people into poverty as it accelerates climate change past an agreed limit of 2 degrees Celsius of warming, development experts warn.

As pressure builds to phase out coal as a power source in favor of cleaner renewable energy, the coal industry has fought back, arguing that coal is the cheapest and most reliable way to bring power to millions without it.

In particular, “clean coal” technology offers emissions 25 to 40 percent lower than traditional coal plants, industry officials say.

But a report by a dozen poverty and development organizations - including the UK-based Overseas Development Institute and the Vasudha Foundation in New Delhi - suggests that falling prices for solar and wind power mean renewable energy is now the fastest and least expensive way to bring electricity to the world’s poor.

In particular, off-grid and “distributed” renewable power - in which smaller-scale clean power systems are built close to areas of demand, avoiding the high cost of expanding national power grids - is “the cheapest and quickest way of reaching over two-thirds of those without electricity”, the report said.

“There are myths that we’re trying to pull up the ladder and deny developing countries the chance to develop the way we did,” said Sarah Wykes, the lead analyst on climate change and energy issues for CAFOD, a Catholic international development charity.

“But you don’t need these kinds of dirty fuels anymore for economic development. There are much better clean alternatives,” said Wykes, one of the authors of the report, in an interview with the Thomson Reuters Foundation.

Around the world, more than 2,400 coal power plants are now under construction or being planned, experts say. Two-thirds of those are in China and India - both countries already struggling with growing deaths from air pollution, the report noted.

Building even a third of those plants would push the world past the international goal agreed in Paris last December to hold world temperature increase to “well under” 2 degrees Celsius, the report said, worsening climate impacts from longer droughts and more severe storms to rising sea levels.

World Bank President Jim Yong Kim has warned if Asia goes ahead its planned coal plants, “I think we are finished. … That would spell disaster for our planet.”

One reason developing countries - and those who fund projects there - continue to look to coal to meet growing energy needs is that it’s what they already know, Wykes said.

“Development finance staff have expertise in fossil fuels and lack skills in renewable,” she said. “There’s a lack of internal incentives, human capacity and the right policy frameworks.”

The coal industry also is a powerful and established lobbying group, she said, with workers who are fighting for their jobs and who would need retraining to take jobs in the emerging renewable energy industry, she said.

But a number of developing countries - including Rwanda and Ethiopia in Africa - have already chosen to invest heavily in renewable energy as their path to development, she said. Nicaragua, in central America, aims to get 95 percent of its electricity from renewables by 2017, she said.

Renewable energy systems also provide more, healthier and higher quality jobs than coal, Wykes said.

But for more developing countries to chose clean power, richer nations need to provide finance and technology to help them, and big development banks and funds - including the Green Climate Fund - need to commit to not financing coal projects, the report said.

Rich countries also need to lead the way by rapidly reducing their own use of coal power and scaling up renewable energy, the authors said.

“Coal undermines both climate and development goals, while clean energy supports them,” said Ilmi Granoff, one of the paper’s authors and a climate and energy researcher at the Overseas Development Institute.