The Environmental Protection Agency, meanwhile, has been publicly slapping down anyone who dares oppose its unprecedented pollution controls.

Obama introducing even tougher greenhouse gas cuts on power plants in an aim to jolt the rest of the world into action ahead of the UN Conference of Parties (COP21) forum in Paris November.

His administration estimates the emissions limits will cost $US8.4 billion ($11.55 billion) every year by 2030, though the actual figure will not become clear until states decide how they will reach those targets.

“They are wrong,” EPA administrator Gina McCarthy said flatly, and in the same breath accused opponents of promulgating a “doomsday” scenario.

McCarthy has been up against it for months as legal challenges pile up against the EPA, leading her to vent at Washington journalists on July 7: “We certainly know how to defend against lawsuits, for crying out loud”

Peabody yesterday urged further action by courts, Congress, states, consumer groups and industrial and residential electricity customers to turn back EPA rules to reduce carbon dioxide emissions on electricity generating plants.

“Studies show the rules will punish American families and businesses with higher energy costs and damage electric reliability, while having no notable benefit even under climate theory,” Peabody said.

“They would put our energy system at serious risk and further slow our nation's tepid economic growth. A technology path – not artificial caps and taxes – is the far better approach to address carbon concerns over time.

“It is clear to us that the rules fail on legal, policy and practical grounds. Unprecedented early opposition to the rules has been advanced from members of Congress, governors, legislatures, attorneys general, and business and consumer groups.

“Americans need relief from ‘pain at the plug’ costs given record electricity rates even amid reduced oil and natural gas prices. Coal provides some of the lowest cost electricity in America and the economy, jobs and households will suffer if these rules move forward.

“Jurisdictions including Europe, Australia, Ontario and California that have tried such policies have suffered soaring electricity costs and economic harm.”

Peabody believes Obama’s administration is forcing utilities to increase the use of renewables and other high-cost fuels, driving up electricity prices.

This past year has been the most expensive year ever for electricity in the US, and electricity rates have increased at twice the pace of household incomes since 2000.

Therefore, Peabody said, mandating greater reliance on the expensive, heavily subsidised renewables the plan required, was not the solution.

It pointed out that after more than 60 years of propping up renewables with more than $85 billion in subsidies, wind and solar only provided about 5% of US electricity.

“America's energy policy should be guided by the dire need for affordable energy faced by more than 100 million Americans who qualify for energy assistance,” Peabody said.

“More than half of Americans also have said as little as a $20 increase in their monthly utility bill would cause hardship.

Peabody believes the US can achieve its environmental goals with an alternative policy path:

• insistence on low-cost electricity
• investment in efficiency improvements at existing plants
• deployment of high-efficiency low emissions supercritical coal plants
• greater research and development to commercialise next-generation coal technologies including carbon capture, use and storage.

The coal player said today's advanced supercritical coal plants were in broad use globally and equipped with technologies that could drive key emissions rates 75% lower than the US coal fleet average.

They also deliver a carbon dioxide emissions rate that is as much as 25% lower than the oldest coal plants in the US fleet.

Every new large supercritical plant offered the equivalent carbon benefit as removing 1 million cars from the road, Peabody said.

Pennsylvania Chamber of Business and Industry president and CEO Gene Barr said while the Clean Power Plan aimed to reduce the electricity sector’s greenhouse gas emissions by requiring significant reductions from coal-fired power plants, grid reliability was at stake.

“By any reasonable measure, these aggressive, far-reaching rules will increase energy costs for consumers and businesses in order to produce a negligible reduction in global carbon emissions,” Barr said.

“The EPA has previously admitted that this rule will result in relatively small reductions in global emissions of less than 2%.”

The chamber advocated passing Act 175 of 2014, which required Pennsylvania’s compliance plan prioritised least-cost compliance options and gained General Assembly endorsement before going to the EPA for approval.

“The EPA’s Clean Power Plan jeopardises Pennsylvania’s role as an energy leader,” Barr said.

“In order to have a strong and robust electric grid that can affordably and reliably provide power, we need to embrace all forms of energy production and recognise the important role that coal, nuclear and natural gas play in our energy portfolio.”