KCP&L announced a dip in third-quarter earnings Thursday due to a cooler-than-normal summer.

Missouri regulators approved an agreement Thursday that establishes a “renewable energy standard” charge on the bills of Kansas City Power & Light electric customers.

The charge, also known as a rate-adjustment mechanism, amounts to an additional 81 cents a month for a typical customer. It will appear as a separate item on the monthly electric bill of KCP&L customers and is expected to begin in December. KCP&L spokeswoman Courtney Hughley said the impact would result in slightly under an additional $10 annually for customers’ bills.

The charge is designed to recover costs associated with Missouri’s Renewable Energy Standard — or Proposition C — created in 2008. The measure requires utilities to implement alternative sources — such as wind, biomass and solar — to their energy portfolios. The rates will apply only to customers in the former Aquila service area.

“Customers should be seeing a notice in their next billing cycle,” Mrs. Hughley said. “We are planning to comply with this and stick with the parameters” of the Missouri Public Service Commission’s action, she added. “We definitely feel like this agreement is fair.”

The new charge was announced the same day that Great Plains Energy, the parent company of Kansas City Power & Light, announced third-quarter earnings Thursday of $147 million, or 95 cents per share. That’s down 3 percent from the third quarter last year.

Terry Bassham, chairman and chief executive officer of Great Plains Energy, said cooler-than-normal summer weather cut into revenue because fewer customers used air conditioning.

The company also announced plans to lower its full-year earnings guidance range to $1.52 to $1.62 a share, down from the previous level of $1.60 to $1.75 per share.

Great Plains’ stock price dropped 4 percent in after-hours trading, to $25.78 a share, after the earnings report was released.

Ray Scherer can be reached

at ray.scherer@newspressnow.com.

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