By Michael Brooks

Two Midwest load-serving entities are challenging a generator interconnection agreement filed by MISO that they say would result in one company paying too much for $5.7 million in transmission upgrades because the RTO is misapplying a provision in its Tariff.

Interstate Power and Light (IPL), which is building the 650-MW Marshalltown Generating Station in Iowa, joined MidAmerican Energy last week in protesting the GIA that MISO filed for the combined cycle plant. The companies told FERC that MidAmerican would end up paying the majority of costs for the transmission upgrades in the agreement, while IPL would only pay the installed cost of capital of the shared network upgrades and not its full portion of the monthly facilities charges contained in MidAmerican’s facility service agreements with transmission owner ITC Midwest (EL16-1083).

The upgrades in the Marshalltown agreement were previously included in GIAs filed for two MidAmerican wind farms. ITC had elected to fund the upgrades itself and agreed with MidAmerican that if they became shared upgrades, ITC would determine each interconnection customer’s cost responsibility for them.

Instead, the companies said, MISO believes that Attachment FF of its Tariff requires IPL to make a one-time cost of capital payment to MidAmerican. The companies argued that Attachment FF only applies to when an interconnection customer, not the TO, is funding the upgrades.

“The MISO Tariff language is silent regarding the instant situation, where ITC Midwest as the transmission owner elected to self-fund the network upgrades,” IPL and MidAmerican said. “MISO has refused to recognize the difference between a situation where the first interconnection customer funded the shared network upgrades and the situation here where the transmission owner self-funded” them.

“The distinction is important because … MISO’s requirement that the second interconnection customer simply make a one-time payment for the cost of the shared network upgrades to the first interconnection customer results in unequal and inequitable treatment of the two interconnection customers for the same upgrades,” the companies said.

The companies said IPL should pay 32% of the costs for a $2 million transformer upgrade and 51.4% for a $3.72 million line rebuild. They asked FERC to order MISO to revise the Marshalltown GIA to reflect these cost allocations.

“Parties should be paying their fair share,” Cortlandt C. Choate Jr., senior attorney for IPL parent company Alliant Energy, said in an interview.

They also asked that MISO be required to revise its Tariff to clarify interconnection customers’ cost responsibilities for upgrades funded by the TO.