In recent years, the Environmental Protection Agency has imposed strict anti-pollution rules on the nation's coal powered utility plants, limiting the amount of mercury and other toxic emissions allowed. These were challenged by 20 states and major power companies in the courts.
The Supreme Court has now sided with the challengers, ruling that the cost of adapting to these regulations should be taken into account.
Ethan Zindler, an analyst from Bloomberg New Energy Finance, told Take Two that most of the country's power plants had already complied with the regulations but the few that haven't will now be rethinking their plans going forward.
"While the deadline to reduce mercury levels has been in place for decades, some companies haven't already put them in place, and the implication is interesting for those who haven't already complied. Some of the old coal plants are having trouble competing with natural gas (which has half the amount of emission that coal plants have)."
The Obama administration has followed a strong environmental agenda, and the new ruling means new proposed regulations will have to be re-examined.
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