Topeka ? Westar Energy Inc. announced it has filed an application with the state to spend $465 million to reduce emissions from its largest and most polluting power plant.

“While our plants operate within today’s rules, this project along with those included in the proposed agreement will allow us to meet the new, even tougher clean air regulations under the Clean Air Visibility Rule,” said Bill Eastman, Westar’s director of environmental services.

The Jeffrey Energy Center, which is near St. Marys, is the highest emitter of carbon dioxide among power plants in Kansas, releasing 18.1 million tons of the gas a year.

Carbon dioxide is one of the greenhouse gases that many scientists believe cause dangerous climate change.

Westar officials said the plan would improve efficiency at the Jeffrey Energy Center while reducing the amount of carbon dioxide produced per megawatt hour of electricity generated.

“As customer demand for electricity grows, we are identifying ways to meet that need with a reduced impact on the environment,” said Doug Sterbenz, executive vice president and chief operating officer.

Westar also said it would reduce emissions by rebuilding sulfur dioxide scrubbers and installing low nitrous oxide emissions systems, and precipitators that remove particulate matter.

Westar’s plan is pending before the Kansas Department of Health and Environment.

Topeka-based Westar is the largest electric utility in Kansas, serving 673,000 customers.