The research, published on World Water Day, found that coal plants globally consume 19 billion cubic metres of water per year.
As of the end of 2013 there were 8,359 installed coal plant units, amounting to 1811GW installed capacity, and 2,668 proposed units, totalling 1300GW proposed capacity globally.
The report warned that, if these plants come online, water withdrawal is set to increase by 32 billion cubic metres per year and consumption by 17 billion cubic metres per year.
It added that, in many areas “water is being used much faster than fresh water bodies can replenish naturally”, with 44 per cent of existing units are clustered in regions of high water stress, and 45 per cent of the proposed units also set to be built in such areas.
Additionally, almost a quarter of over-withdrawn regions are using more than five years’ worth of renewable freshwater resources each year, according to the study.
The report called on policy makers in the worst affected “red-list areas” to stop licensing new coal-fired plants. However, it said that alone would not be enough to resolve the problem.
It therefore called for the retirement of all coal-fired plants which are more than 40 years old.
A study published earlier this year by researchers at Wageningen University in the Netherlands warned that a significant proportion of the world’s power plants will become less efficient as a result of reduced water resources due to climate change.