Alliant Energy’s Iowa unit lines up a DOE-backed loan of up to $3.5 billion (NASDAQ: LNT)

Posted by Donna Armstrong on Oct 28th, 2026

What happened

Alliant Energy Corporation (NASDAQ: LNT) subsidiary Interstate Power and Light Company (IPL) can borrow up to $3.5 billion through a new Energy Department-backed facility. Wisconsin Power and Light Company (WPL) signed a parallel agreement capped at $1.63 billion.

On Oct. 26, each utility signed a loan guarantee agreement with the U.S. Department of Energy, a note purchase agreement with the Federal Financing Bank and a future advance promissory note. Alliant Energy is not a party to the loan documents. Each utility's borrowings are full recourse, senior unsecured obligations of that utility.

The bank sets the rate on each advance when it is made. The rate is the U.S. Treasury rate plus 37.5 basis points. All borrowings mature May 15, 2056. Proceeds reimburse up to 80% of eligible project costs, which may include generation, transmission, substations and energy storage.

Key numbers

Metric	Latest	Source
IPL maximum advances	$3.5 billion	SEC 8-K
WPL maximum advances	$1.63 billion	SEC 8-K
IPL cap above WPL cap	$1.87 billion	Calculated from SEC 8-K
Spread over U.S. Treasury rate	37.5 basis points	SEC 8-K
Share of eligible project costs reimbursable	Up to 80%	SEC 8-K

Why it matters

IPL's cap is $1.87 billion above WPL's, so the Iowa utility holds the larger pool of federally guaranteed borrowing capacity.

OptimistFi has argued that Alliant's growth depends on Wisconsin and Iowa regulators allowing cost recovery. The facilities tie to that directly. The Iowa Utilities Commission (for IPL) or the Public Service Commission of Wisconsin (for WPL) may approve costs in final orders that fall short of a 95% recovery threshold. If so, the utility must prepay certain amounts. That test comes on the second anniversary of the end of the availability period.

The amounts are ceilings, not borrowings. Advances depend on state regulatory approvals, completion of the Energy Department's environmental review and confirmation of investment grade credit ratings. Prepayments under $1 billion are paid over one year. Those of $1 billion or more are paid over four years. OptimistFi reads the filing as mixed for the case.

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What's next

If a utility has not drawn its first advance within 18 months after its agreement's effective date, the Energy Department may end that agreement on at least 10 business days' notice. A first advance by IPL or WPL before that cut-off would show the projects are clearing the conditions.

Each utility may request advances once per calendar quarter and no more than four times a year. That runs until Sept. 15, 2033 or until its cap is reached, whichever comes first.