Wichita ? Westar Energy said a U.S. Supreme Court’s ruling on toxic emissions at power plants could save the company millions.

The Supreme Court ruled Monday that the Obama administration should have considered potential costs when it issued rules regulating toxic emissions from power plants, The Wichita Eagle reported.

The utility already has spent $16 million to help bring its four coal-powered plants in Kansas into compliance with the Environmental Protection Agency’s mercury-reduction rules, said Brad Loveless, executive director of environmental services. The ruling delayed implementation of the regulations, although they are in force while a lower court reconsiders the issue.

Loveless said that the court decision will — for now– save the utility $8 million on the project, plus another $5 million a year for supplies. The utility will take no further action until the rules are clarified.

High levels of mercury can harm the brain, heart, kidneys, lungs and immune system, according to the EPA’s website. It’s particularly dangerous to unborn babies and can harm the developing nervous system.

The Supreme Court ruling didn’t say that the EPA couldn’t regulate mercury emissions nor did it require the agency to forgo regulations if the cost is more than dollar value of environmental and health benefits. But the justices did say regulatory decisions have to be appropriate.

“The phrase ‘appropriate and necessary’ requires at least some attention to cost,” said the court opinion, delivered by Justice Antonin Scalia. “One would not say that it is even rational, never mind ‘appropriate,’ to impose billions of dollars in economic costs in return for a few dollars in health or environmental benefits.”

The court’s ruling doesn’t affect an ongoing rate case before the Kansas Corporation Commission. Westar wants an additional $125 million a year in rates, which works out to around $13 a month for the average residential customer.