Coal India (CIL) is in the process of setting up 20 new washeries with an annual capacity of 111 million tonne. Currently, it operates 17 washeries with an annual capacity of 39.4 million tonne, reports suggest.

Environment activists and power plants, who use coal, are demanding that coal be supplied after it is treated in washeries so that impurities are removed.

According to a study by the US Department of Energy, the use of washed coal reduces carbon dioxide emissions by 11 per cent.

Washed coal does not have impurities such as ash, soil, rocks and hence it burns longer and provides more energy. Most of the imported coal is washed whereas majority of Indian coal which costs much less is of the unwashed variety.

A UK-based minority stakeholder of CIL alleges that the firm supplies majority of coal to power companies in India without treating them in washeries and hence it contains 30-50 per cent ash.

Washed coal, besides being more environment-friendly, fetches better prices and is of better quality.