TOPEKA, Kan. (AP) -- A Kansas Senate committee is considering a proposal to change or delay renewable energy requirements for the state's major utility companies amid complaints about higher energy costs.

A law passed in 2009 requires utilities to generate 15 percent of their energy through a renewable source by 2016 and 20 percent by 2020.

The Senate Standing Committee for Utilities is considering delaying the 15 percent requirement to 2018 and the 20 percent requirement to 2024. It also would allow utilities to delay the requirements if they show "good cause," which would include increased costs to the customers, The Lawrence Journal-World reported (http://bit.ly/XLxH5g ).

Proponents and opponents of the standards debated the proposal Tuesday, following a hearing last week before a joint House-Senate committee.

"Our renewable standards are a failure," said Rep. Charlotte O'Hara, R-Overland Park. "They resulted in higher energy costs ... and are not the answer to our energy independence. It's time to recognize this failure, repeal the RPS and be free from these crippling energy mandates."

The Kansas Renewable Standards Act was passed in 2009 as part of an agreement that allowed construction of an 895-megawatt coal-fired power plant in Holcomb. But in January 2012, a court ruled that the power plant could not be built until after an environmental review.

"The power plant expansion has not occurred and is not expected to occur in the future because of lawsuits and restrictions," said Rep. Dennis Hedke, chairman of the Energy and Environmental Policy Committee. "There's still folks not at all happy that the plant has not been allowed to move forward."

Hedke, a consulting geophysicist at Hedke-Saenger Geoscience Ltd., which has clients in the oil and energy industry, said it's unlikely the energy act will be repealed but there is "a high probability" that it could be modified.

"Even if you just took the first part of it, the 2015 standards, and live with them, and removed the 20 percent mandate, then you would still have a significant modification," he said.

Representatives from environmental groups and wind power companies testified against the proposed changes Tuesday, arguing that loosening the renewable standards would hurt economic activity sparked by wind energy in the state.

"Modifying the RPS would absolutely send a strong negative signal that would likely cripple the emerging export market," said Matt Riley, CEO at Infinity Wind Power. "To my knowledge, not one of the 30 other states with an RPS has negatively modified or repealed that important policy. Kansas would be the first to do so, and it would send a shockwave through our industry, saying, 'Thank you very much for the $3 billion of investment last year, but you're not welcome here anymore."'

The Energy and Environmental Policy Committee will hear more testimony next Tuesday.