AGL Energy’s decimated board is coming under immediate pressure from large shareholders, led by tech billionaire Mike Cannon-Brookes, to bring forward its exit from coal power generation by 10 years or more after it was forced into a humiliating backdown on a plan to split the business.

The ditching of the demerger proposal confirmed by the country’s biggest electricity supplier on Monday claimed the scalps of chairman Peter Botten and chief executive Graeme Hunt, as well as two non-executive directors.