WARWICK, R.I. — Climate emissions are a contentious issue in deciding the fate of the natural gas/diesel power plant proposed for the woods of Burrillville. But agreeing on how to measure the carbon pollution consumed most of the day during the Sept. 18 Energy Facilities Siting Board hearing.

Invenergy Thermal Development’s star witness, Ryan Hardy, an independent energy market consultant, challenged every question put to him by Jerry Elmer, senior attorney for the Conservation Law Foundation. Elmer sought to make the case that the nearly 1,000-megawatt power plant would prevent Rhode Island from achieving its climate pollution reduction goals.

But Hardy said the emission projections that Invenergy submitted to the Rhode Island Department of Environmental Management for an air pollution permit aren’t an accurate portrayal of likely carbon dioxide emissions when the plant is operating.

Using the air pollution permit numbers, Elmer calculated that 799 pounds of carbon emissions per megawatt-hour, or almost 7 billion pounds of carbon annually, compared to 710 pounds of carbon emissions per megawatt-hour on average for all of New England.

“I wouldn’t calculate it this way,” Hardy said. “I would not use these numbers to project that emissions. … I’m happy to do the arithmetic but I don’t agree with the calculation.”

The testimony then centered on the debate of using consumption-based or production-based accounting of emissions. Invenergy and Hardy use the consumption-based accounting of emissions, while opponents of the power plant measure emissions produced by Rhode Island power plants.

Elmer noted that the Massachusetts Global Warming Solutions Act uses production-based accounting, an approach that was affirmed in court. Invenergy, however, disputes that the Massachusetts regulations uses production-based accounting.

Ryan admitted that under consumption-based accounting emissions in Rhode Island would increase. While on a regional bases, emissions would be reduced by 1 percent because of the new power plant.

“Location does not matter when it comes to CO2 emissions,” Ryan said.

At the end of questioning, Energy Facility Siting Board (EFSB) member Janet Coit confirmed an emissions decrease in Rhode Island and the region under the consumption-based accounting method.

Energy markets consultant Ellen Cool testified on behalf of the Rhode Island Office of Energy Resources. Cool’s advisory opinion concluded that the proposed Burrillville power plant wouldn’t prevent Rhode Island from achieving its carbon-reduction goals.

The emissions debate is set to continue Sept. 20 with the cross-examination of Brown University professor and climate-change expert Timmons Roberts.

The hearings are held at the PUC building, 89 Jefferson Blvd. in Warwick, conference room A at 9:30 a.m. The final stage of hearings are expected to continue on various dates through Nov. 27.