Saskatchewan Environment Minister Dustin Duncan says he's negotiating a deal with federal counterpart Catherine McKenna on carbon.

Duncan wants McKenna to let his province get credit for the carbon capture and storage system it has on one coal-fired power plant to offset the emissions from continuing to use at least one other plant without such a system after 2030.

Duncan says several plants in the province would have to be retrofitted before 2030 to keep them operating, but there is one that won't hit its 50-year lifespan until 2042.

Saskatchewan currently relies on coal for more than half of its electricity.

Keith Stewart, a senior energy strategist at Greenpeace Canada, says Saskatchewan's plan is ridiculous and Canada's international coal phase-out push will be undermined if McKenna allows it.

Nova Scotia, which uses coal for almost 60 per cent of its electricity, is also negotiating an equivalency agreement with Ottawa.

A spokesperson for the New Brunswick government said yesterday that getting rid of its only coal plant by 2030 would be ideal but that will only happen if Canada comes up with "adequate support."