TORONTO -- Ontario consumers won't see a separate line item on their natural gas bills showing the cost of the Liberal government's cap-and-trade plan to fight climate change.

The Ontario Energy Board has decided charges related to the cost of the program, which is aimed at reducing greenhouse gas emissions, will be included in the 'delivery' line charge on natural gas bills.

The board admits utilities and industrial natural gas users argued for a separate line item to provide greater transparency to customers about the cost of cap-and-trade, but it says consumer groups said that wasn't necessary.

The opposition accuses the government of trying to "bury the evidence" that cap-and-trade is another "cash grab," and says it's "apparent" that the energy board is more concerned about protecting the Liberals than consumers.

PC energy critic John Yakabuski says people have a right to know exactly how much the government's climate change plans will cost them every month.

Yakabuski says to make matters even worse, consumers will pay the HST on top of the cap-and-trade costs, which he says amounts to "a tax on top of a tax."

Ontario will join an existing cap and trade market with California and Quebec next January, mandating emission limits on polluters but allowing them to buy emission credits or sell them to other companies if they are under their limit.

The province plans to spend up to $8.3 billion on programs to encourage people and companies to switch to more energy-efficient heating systems, buy electric or hybrid cars, convert big trucks to natural gas, add more bio-fuel to gasoline, and help the agriculture and industrial sectors adopt low-carbon technologies.

Most of the money for those plans will come from cap-and-trade, which the Liberals predict will raise $1.9 billion a year, all of which will go into a dedicated fund for lowering Ontario's carbon footprint.