Late last week, Ernst & Young hosted a one-hour webcast on the corporate world’s response to climate change, entitled “Business response to climate change: Corporate transformation, funding and public policy.” Speakers included Eric Langevin (Senior VP, Kadant); Andy Brown (Chief Technology Officer, Delphi); Steve Starbuck (Americas Director of Climate Change Tax Matters, E&Y); and Joe Muscat (Americas Director of Cleantech & Venture Capital, E&Y).

The main takeaway is that businesses are throwing money at climate initiatives and other “green” causes — but what do shareholders get in return? What do consumers get in return? Obviously, the businesses get generous subsidies and tax breaks, but what about the rest of us?

Some highlights of the webcast:

– The four main drivers behind corporate America’s response to climate change: government regulation, cost reduction, revenue generation, and expectations.

– Steve Starbuck said that developers of wind farms have a “difficult time making the economics work on their own.”

– From one of Delphi’s slides: “Global warming from greenhouse gases is now almost universally accepted as a significant threat; Economic and ecological security is threatened.”

– From an E&Y survey of 150 industrial and financial companies: (1) Climate-change corporate commitments total $276 billion over the next 10 years; (2) Clean-tech investment in 2007 totaled $70 billion; and (3) 90 percent of companies are undertaking climate-change initiatives.

One thing I did not learn from the webcast — and I’m trying to find out — is how much companies are spending on carbon offsets that represent actual CO2 reductions. “Green” initiatives and investments have snowballed, and apparently few businesses are choosing not to jump on board. But where’s the return on this investment?

Take CO2-reduction projects, for example. Even if companies can reduce CO2 emissions, will it be worth their shareholders’/investors’ capital? Given that there is no definitive proof that manmade CO2 leads to accelerated warming, and given that we do not know what, if any, benefit will result from reducing CO2, should businesses be pouring billions of dollars of investor value down the carbon sink?