Outgoing ERM Power chief executive Jon Stretch has delivered a scathing assessment of energy policy at the business electricity retailer's last annual meeting before its $617 million takeover by Shell, a deal that will transform the country's power retailing sector.

Speaking after ERM shareholders delivered an emphatic 99.74 per cent endorsement of the deal, Mr Stretch, who will exit once the takeover completes, took aim at "populist" and "interventionist" moves by government that discourage investment.