For consumers in most of the country, the plan's impact on rates should be small.
The Chamber of Commerce said last week that rates would rise by $17 billion a year. States like California and those in the Mid-Atlantic that have little reliance on coal will see almost no change, while seven Southern states that use more coal will shoulder a $6.6 billion annual rate hike.
But the Chamber's analysis projected a bigger mandated cut in emissions than what actually happened and used a more aggressive forecast than the government's as to how much power demand would grow without new rules. If people use less power, the impact on their budgets would be smaller.
The EPA's McCarthy argued that power costs for consumers will actually drop overall. When the rules are fully implemented, rates will be 8 percent lower than they would have been otherwise, she said at a press conference in Washington, in part because of more investment in renewables and conservation.
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"Critics claim your energy bills will skyrocket,'' she said. "Well, they're wrong."
For investors, the concern is whether the rules will hurt utilities' ability to pay the dividends and bond interest payments many income-seekers such as retirees count upon. Most of the 15 stocks in the Dow Jones Utilities Average pay yields of 3 percent or more, with Southern (NYSE:SO) the highest, at 4.8 percent. That shouldn't be a huge problem, said Fishman and Ryan Wobbrock, a utilities analyst at Moody's Investors Service, the bond ratings firm.
The reason is that regulators in states that regulate power generation usually let utilities pass along the cost of capital improvements to rate payers, whether for new natural-gas-fired plants to replace phased-out coal terminals or to add pollution-control equipment to coal plants that can meet the new targets if they're modernized, Wobbrock said.
"The U.S. regulatory environment is very supportive of the credit profiles of utility companies," Wobbrock said. "Over the years, we've seen increased willingness to give utilities cost-recovery mechanisms for prudently incurred costs.''