New York state used a new tactic last week to try to prompt coal-fired power plants to clean up their climate changing emissions: concern for shareholders. State attorney general Andrew Cuomo sent letters and subpoenas to five coal-lovin’ power companies on Friday requesting internal documents and questioning if investors had been given adequate information on the financial liabilities that could result from CO2 emissions at their planned power plants. “Any one of the several new or likely regulatory initiatives for CO2 emissions from power plants — including state carbon controls, EPA’s regulations under the Clean Air Act, or the enactment of federal global-warming legislation — would add a significant cost to carbon-intensive coal generation,” the letters said. Activist shareholder groups have been seeking such disclosures for years. Alas, New York’s tactic could not likely be used in many other states since Cuomo’s investigation is aided by a 1921 state law predating the federal Securities and Exchange Commission that gives the New York attorney general broad powers to subpoena companies’ records. The businesses under scrutiny are AES Corp., Dominion Resources Inc., Dynegy Inc., Peabody Energy, and Xcel Energy.

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