Microsoft signs 20-year power deal with NiSource for Indiana data centers

Microsoft has signed a 20-year power purchase agreement with Indiana utility NiSource, starting in 2028, to supply a planned data center campus in northern Indiana with roughly 1.1GW of new generation and transmission capacity.

The contract runs through NiSource's subsidiary NiSource Generation Company LLC (GenCo). Under the deal, GenCo will add around 1.1GW to the utility's power portfolio and build the transmission and generation infrastructure the campus requires.

As part of the agreement, GenCo has contracted 600MW of battery storage under a tolling agreement. An affiliate of AGP Group will construct the storage facility.

Who pays for the new capacity?

The campus falls under a new large-load rate structure. NiSource says the rate class protects existing customers from price rises because large-load users must fund the generation and infrastructure needed to power their own facilities.

"Affordability is not separate from economic development; it is a key pillar of our GenCo model," NiSource president and CEO Lloyd Yates said. "This agreement reflects the balanced approach we believe is needed for Indiana to attract significant investment and create long-term jobs."

Jeff Riles, senior director of energy markets at Microsoft, framed the deal the same way. "Microsoft has always been committed to paying our own way and identifying long-term solutions like this one to ensure that our data centers don't increase electricity prices for other ratepayers," Riles said. "Our partnership with NIPSCO will not only support continued growth and protect ratepayers but also help to support a reliable grid for years to come that the communities of Northern Indiana rely on."

Which site will the power serve?

Neither company has confirmed the exact facility. The terms point to Microsoft's data center under construction in La Porte, Indiana.

That project dates to at least 2024, when Microsoft announced a 245,000 sq ft (22,800 sqm) data center on 489 acres at Radius Industrial Park, part of a $1bn investment in Northwest Indiana. The first phase called for six data centers and a substation on the initial plot.

In April 2026, Microsoft disclosed revised plans: 17 buildings on an expanded plot between East 250 South, East State Road 4, and Stevens Road in La Porte. The company has not specified how many of those buildings will function as data centers.

Microsoft also owns 939 acres in Mishawaka, Indiana, a site widely expected to host another data center.

The message from both signatories is simple: the 1.1GW arrives in 2028, and large-load customers, not existing ratepayers, carry the cost.