The Missouri Public Service Commission approved Ameren Missouri’s rates for data centers and other large electricity users on Monday.
The Public Service Commission voted unanimously to accept Ameren’s tariff proposal for customers using 75MW or more of electricity per month, which is more than double the largest customer in Ameren’s service area in 2024. The proposal was also supported by the Sierra Club, Renew Missouri, staff of the Public Service Commission, Google and Amazon. The Office of Public Counsel, which advocates for customers of investor-owned monopoly utilities in Missouri, did not support the agreement but also did not object.
The Missouri Legislature passed a law this year, SB4, which prompted utilities to create tariffs for large load customers like data centers. The law required those rates to “prevent other customer classes' rates from reflecting any unjust or unreasonable costs arising from service to such customers.”
The new tariff includes provisions to protect other customers from having their rates go up because of data centers moving into Ameren Missouri’s service area. Those include a minimum service term of 12 years, early exit fees if data centers try to leave earlier than their contract or use less energy than was initially asked for, and two years of notice for terminating a contract or reducing the energy needed.
The tariff also creates four new subscription programs for customers who want to pay more for specific types of energy, like wind, solar or nuclear. In filings, Ameren Missouri representatives said many data center customers have ambitious goals to reduce greenhouse gas emissions from their operations, which made creating these new programs necessary.
Ameren will also be required to create annual compliance reports on large load customers.
The PSC approved a similar tariff for electric utility Evergy in Kansas City earlier this month.
