Nipsco Indus. Grp. v. N. Ind. Pub. Serv. Co.

Slaughter, Justice.

Under traditional rate regulation, an energy utility must first make improvements to its infrastructure before it can recover their cost through regulator-approved rate increases to customers. The process for recouping these costs, sometimes not until years after they were incurred, is an expensive, onerous ratemaking case, which involves a comprehensive review of the utility's entire business operations.

In 2013 the legislature authorized utilities to obtain regulatory preapproval for "designated" improvements to their infrastructure. Under the so-called "TDSIC"

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