The Missouri Legislature has passed a measure that could allow the biggest electric companies in the state to recover more of their costs for infrastructure improvements from customers.

If this senate bill becomes law, Ameren Missouri customers will see a 5 percent reduction in electric rates due to the federal government tax break recently signed into law.

The bill, approved by the House Wednesday 125-20, affects the nearly 2 million people who use The Empire Electric District, Ameren Corp. and Kansas City Power & Light Co. across the state. Companies would be given more flexibility as to when and how they changed their rates, in response to declining electricity usage.

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Proponents say this change will help modernize the state's electrical grid.

In a statement, Ameren Missouri said:

Today's action by the Missouri House of Representatives to pass SB 564 will accelerate modernization of the electric grid for a smarter, more resilient and secure grid while providing our customers greater stability through rate cuts and caps. This legislation will result in an almost 5% reduction in electric rates within 90 days after being signed into law to reflect federal tax cuts. In working to modernize the electric grid, lawmakers and stakeholders have crafted a bipartisan compromise that will greatly improve Missouri's energy infrastructure for the benefit of our customers and the entire state.

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Warren Wood, vice president, external affairs & communications, Ameren Missouri

Not included in Ameren Missouri's statement to News 4 is a rate increase that could come two years from now, in 2020.

"Each year, rates could increase by 2.85 percent but they would have to file a case with the [Public Service] commission, and the commission will look at all relevant fractures to see if that rate increase should be allowed," said Natelle Dietrich, with the Public Service Commission.

Opponents say this could dramatically increase what customers are paying. Cara Spencer with the Consumer Council of Missouri says they are fighting this senate bill. Spencer believes the rise in rates will hurt some of the most vulnerable, including, "Fixed incomes, some of our older residents, some of our residents living in poverty, who are already making tough choices between paying their utility bill and having a bite to eat," said Spencer.

Spencer also thinks it's unfair that Ameren Missouri is the only electric company in the St. Louis area. "The consumers who have no choice, will have to pay for them and that's a real concern here," said Spencer.

The bill next goes to the governor.

The bill is SB 564

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