Offsetters, the official carbon offset supplier of the 2010 Winter Games, says it's aiming to pull off a carbon neutral Olympics – but critics say offsets alone can't deliver on the promise.

By VANOC estimates, the 2010 Games will directly produce 118,000 tonnes of carbon emissions. An additional 150,000 tonnes are expected to come from indirect emissions, attributable to flights and lodging for Games spectators, media and corporate sponsors.

It's a hefty environmental price tag, but one that Offsetters president James Tansey says offsets can balance.

"We're very confident that offsets reduce emissions," Tansey said.

Offsets are financial subsidies that companies provide to other businesses so that they can upgrade to greener technology.

Sunselect Produce in Aldergrove, B.C., for example, has switched from a natural gas heating system to a biomass boiler that burns wood waste thanks to offset investments.

"Finally, you're combining economics with environmentalism," Sunselect's Victor Krahn said. "We're really excited about it."

But offsetting the Games is still a massive undertaking, and Offsetters is turning to Olympic spectators for help.

For a donation of $25 per ton of carbon dioxide offset, Games-goers will receive a commemorative certificate and a limited edition 2010 pin for their effort.

But Mark Jaccard, an environmental management professor at Simon Fraser University, says while offsets may make organizations feel better, they aren't as reliable as some might suggest.

"We need to be very careful about this kind of correspondence, that an offset exactly reduces the emissions that you would otherwise cause by heating a building, driving a truck and so on."

Jaccard is part of a global team of researchers that have been studying the effectiveness of carbon offset programs – and their findings are less than reassuring.

"We're trying to estimate what the real effect of various kinds of subsidy programs are, like offsets," Jaccard said.

"The general research is finding that something like 50 per cent of this is not really reducing emissions."

The only way to truly reduce carbon emissions would be to physically take the carbon dioxide from the atmosphere and put it into the ground, he added.

Offsetters has not yet to secure enough projects to balance the more than 300,000 tonnes of carbon the Games are expected to produce, but they have until 2012 to complete the massive project.

We'll have a better idea then whether the growing carbon market has really made a difference in fighting climate change.

With a report from CTV British Columbia's Mi-Jung Lee