Missouri enacted legislation (S.B. 54) in June 2007 requiring all of the state's electric utilities -- including municipal utilities and electric cooperatives -- to offer net metering to customers with systems up to 100 kilowatts (kW) in capacity that generate electricity using wind energy, solar-thermal energy, hydroelectric energy, photovoltaics (PV), fuel cells using hydrogen produced by any of these resources, and other sources of energy certified as renewable by the Missouri Department of Natural Resources. Systems must be intended primarily to offset part or all of a customer's own electrical energy requirements, and must be located on a facility owned, operated, leased or otherwise controlled by the customer. Administrative rules to implement S.B. 54 adopted by the Missouri Public Service Commission (PSC) took effect in February 2009. A subsequent June 2009 rulemaking order
revised insurance requirements for customer-generators, effective September 30, 2009.
The PSC's rules only apply to the state's investor-owned utilities. Utilities not regulated by the commission -- electric cooperatives and municipal utilities -- were required to adopt initial rules by October 1, 2008, including regulations ensuring that simple contracts will be used for interconnection and net metering. The adopted rules include an all-in-one document that includes a simple interconnection request, simple procedures, and a brief set of terms and conditions.
Utilities must offer a net-metering tariff or contract that is identical in electrical energy rates, rate structure, and monthly charges to the contract or tariff that the customer would be assigned if the customer were not an eligible customer-generator. Utilities may not charge the customer any additional standby, capacity, interconnection, or other fee or charge that would not otherwise be charged if the customer were not an eligible customer-generator.
Systems must meet all applicable safety, performance, interconnection and reliability standards established by any local code authorities, the National Electrical Code (NEC), the National Electrical Safety Code (NESC), the Institute of Electrical and Electronics Engineers (IEEE), and Underwriters Laboratories (UL) for distributed generation. Utilities may require customers to provide a switch, circuit breaker, fuse or other easily accessible device or feature that allows the utility to manually disconnect the system.
In June 2009 the PSC adopted a minimum liability insurance requirement of $100,000 for systems larger than 10 kW. Systems of 10 kW and smaller are not required to have additional liability insurance. Insurance requirements may be met with an additional insurance policy or an endorsement on an existing policy. These requirements replace the former $100,000 minimum requirement for systems of up to 10 kW and $1 million minimum requirement for systems larger than 10 kW.
Applications for interconnection must be accompanied by a plan for the customer's system, including a wiring diagram and specifications for the generating unit. Utilities must review and respond to the customer within 30 days for systems up to 10 kW, and within 90 days for systems greater than 10 kW. Prior to interconnection, a customer must furnish the utility with certification from a qualified professional electrician or engineer that the installation complies with the established safety and operating requirements.
Any costs incurred by a utility under Missouri's net-metering statute are recoverable in the utility's rate structure. The estimated generating capacity of all net-metered systems counts towards the respective utility's accomplishment of any renewable-energy portfolio target or mandate adopted by Missouri. Each utility must file an annual report describing the status of its program.