Global Infrastructure Partners and Canada Pension Plan Investment Board agreed to acquire Allete Inc., a Minnesota-based utility owner, for about US$3.9 billion.

The companies will acquire all the outstanding common shares of Allete for $67 a share in cash, a 19 per cent premium to the utility owner’s closing share price before a media article reported the deal in December, according to a statement Monday. The tie-up is valued at $6.2 billion including the assumption of debt.

The acquisition comes as U.S. electric utilities are facing the biggest demand jump in a generation. Booming interest in artificial intelligence is spurring development of data centers, while new factories and efforts to electrify more of the economy are all taxing the U.S. power grid. 

Allete’s Minnesota Power utility serves 150,000 customers and has clean-energy development operations.

Allete shares were down 0.4 per cent in pre-market trading in New York,

JPMorgan Securities LLC is Allete’s lead financial adviser on the deal, which is expected to close in mid-2025 pending shareholder and regulatory approvals.