The proposal by NB Power to convert the Coleson Cove Generating Station to natural gas would be an "appalling waste of a non-renewable fossil fuel," according to an environmental leader.

NB Power is weighing a proposal to switch part of the province's largest thermal generating station to natural gas was outlined in a letter obtained by CBC News.

The provincial power utility confirmed the plans, saying the proposal is still preliminary but the decision to move forward with the next phase of the project could be made by late summer.

David Coon, executive director of the Conservation Council, said the plan to convert Coleson Cove does not make a lot of sense.

"It's an appalling waste of a non-renewable fossil fuel," he said. "If you are going to burn gas it has to be done efficiently and cost-effectively."

Coon said retrofitting the 35-year-old thermal generating station would not be the most efficient use of money or fuel.

He said it would be better for NB Power to build a new co-generation plant or a combined-cycle natural gas power plant.

Gordon Dalzell, a Saint John clean air activist, said he agrees with the Conservation Council that the conversion to natural gas could be bad for the local environment.

He said natural gas is cleaner than oil, but it still contributes to ground level ozone and acid raid.

But Dalzell said it could be better regionally if New Brunswick exports to Nova Scotia and gets rid of the coal-fired plants there.

"The atmosphere doesn't care where the greenhouse gases come from, the idea is to get them reduced," Dalzell said.

The governments of New Brunswick and Nova Scotia have discussed adding a new transmission link between the two provinces. 

A NB Power official said on Wednesday the conversion project would allow Coleson Cove to operate more often. Coleson Cove currently sits idle the majority of the time because it is too expensive to operate.

NB Power said it hopes to know by late summer if the utility will move forward with the next stage of the project.

Instead, it is cheaper for NB Power to import electricity than to use the oil-fired station.

NB Power had spent $747-million in a major overhaul of the facility that upgraded the power plant and would have allowed the facility to burn the cheap water-and-bitumen mixed fuel called Orimulsion.

That plan was scuttled when the Venezuelan government said it would not honour its contract. Since that time, NB Power has experimented with burning petroleum coke at Coleson Cove as a way to cut down on the fuel costs.

Environmental benefits

The proposed plan would also cut down on the greenhouse gas emissions, according to NB Power.

Coal-fired facilities emit 800 tonnes per gigawatt hour of greenhouse gases and oil-fired plants emit around 750 tonnes per gigawatt hour. The natural gas plant would reduce emissions to between 400 to 500 tonnes per gigawatt hour, NB Power said.

But Coon said the emissions would actually be higher with a natural gas-fired plant because it would operate more often than it does now.

"If they have natural gas there they will, as long as the price remains low, which is no guarantee, they will use [Coleson Cove] instead of purchasing power [from the United States]," he said.

The conversion plan could move forward without an environmental impact assessment.

The Department of Environment said in its letter that if the proposal does not change, the conversion to natural gas could be done without an environmental review.

Dalzell said he an environmental review is necessary.

"I'm surprised, shocked quite frankly," he said.

"This is totally inappropriate and not acceptable because no matter what this project entails, the public does need the opportunity to have a public review."

Dalzell said natural gas may be cleaner than oil, but it can still contribute to ground level ozone and acid raid.

The environment department said there would still need to be some regulatory oversight if the project moves ahead.

For instance, a proposed pipeline would likely trigger an environmental review.

As well, the department said NB Power would need to have its permit to operate changed and there could also be the requirement for an Energy and Utilities Board review.