The writer and comedian made the promise last week to pressure the schools to sign on to a global movement calling for a total divestment of fossil fuels.
"Primarily it's a moral argument, where if you're an institution that claims to be working in the public interest, you can't do that and also be invested in fossil fuels, because torching the climate isn't in the public interest," said Vrooman.
The fossil fuel divestment movement, started by environmental group 350.org in November 2012, has started to gain traction abroad but so far failed to take hold in Canada.
Last fall, Dalhousie University rejected calls to divest of fossil fuels, while the University of Calgary pre-emptively said it was not looking at making changes to its investments in the energy industry.
Concordia University has promised to make $5 million of its roughly $130 million endowment fossil-free, and several other schools are considering divestment proposals, but no Canadian university has actually signed on to fully getting rid of its fossil fuel investments.
Outside Canada, hundreds of colleges, cities, foundations and religious groups have committed to some degree of divestment of fossil fuels.
Just last week, Oxford University said it will not directly invest any of its $3.3 billion endowment in coal or oilsands, joining the Rockefeller Brothers Fund which late last year committed to phasing out coal and oilsands investments from its roughly $1.1 billion fund.
Toronto's Trinity-St. Paul's United Church is one of the few Canadian groups outside of environmental organizations to sign on to the movement.
Jeanne Moffat, a member of the congregation who pushed for divestment, says the decision was about sending a message.
"We don't have any illusions that taking our small bits of money at Trinity St. Paul's is going to affect the fossil fuel industry per se," said Moffat. "But we do know that what's being affected is a questioning of their social licence to operate as if there's no tomorrow."
But even those pushing for climate change action question the effectiveness of the campaign. Bob Walker, vice-president of NEI Ethical Funds, says it's better to work with companies to bring about policy changes such as putting a price on carbon.
"We've been engaging companies for 15 years, and from our experience you can't change a company you don't own," he said.
"Once we divest from a company our voice is gone."
He said it's time to create better policies in collaboration with the energy industry aimed at combatting climate change.
"Now is the time to gather voices, to build consensus, not to be pointing fingers and polarizing the debate."
Werner Antweiler, an environmental economics expert at the University of British Columbia's Sauder School of Business, says that while he is a strong supporter for action on climate change he thinks the divestment movement is flawed.
"I'm concerned that pushing universities to divest is actually not particularly helpful, simply because it's so difficult and fraught with a lot of practical problems, and it won't shift the policies of these fossil fuel companies," said Antweiler.
"It also opens up the universities to being hypocrites because we all use fossil fuels, and if you divest from fossil fuel companies, how can you do that and at the same time drive a car?"
But Vrooman says the movement is part of a larger campaign.
"No one involved with divestment expects it will be a grand solution, but it's one important front of many going on."
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