Concord — A settlement agreement that calls on Eversource Energy to sell all of its New Hampshire power plants has hit delays.

The hold up is at the Public Utilities Commission, where state energy regulators have yet to approve or reject the deal. A decision is expected any day, but until then, any plans to auction off Merrimack Station in Bow, N.H., are on ice.

The settlement reached last year requires Eversource to sell its nine hydro facilities and three fossil-fuel plants, including coal-fired Merrimack Station, Newington Station and Schiller Station in Portsmouth, N.H.

PUC commissioners must determine whether the deal is in the public’s interest, and are expected to consider its effect on local communities, and whether the agreement fairly distributes costs among ratepayers.

Eversource had hoped for a verdict by the end of 2015, and in the case of an approval, anticipated the plants could go up for auction by early 2016.

But hearings ended in February, and the PUC has yet to issue a decision.

“I understand the need for due deliberation, and I understand the three PUC commissioners are overwhelmed,” said Sen. Jeb Bradley, who worked on the settlement and sponsored legislation to move it forward. “I continue to be hopeful the divestiture can proceed.”

A PUC spokeswoman didn’t respond to a request for comment.

The deal would resolve a lengthy legal battle over how much Eversource customers will pay for a $422 million mercury scrubber the utility installed at Merrimack Station. Eversource would forgo recovering $25 million of the scrubber’s cost.

If a sale is completed, Eversource would purchase power on the competitive market, in line with the practices of other utilities in the state.

Settlement supporters said the projected $300 million cost savings for ratepayers depend on the plants quick sale.

Bradley said he doesn’t expect the ongoing delay to impact those estimates, unless a decision is years away.

Eversource has been preparing for an eventual sale. In November of last year, the utility used drones to shoot marketing video of the plants from above.

“We’re looking forward to receiving the commission’s forthcoming decision and carefully reviewing it,” said spokesman Martin Murray.

It’s not clear what Merrimack Plant would fetch in an auction. The settlement would provide for three years of property tax stabilization for Bow if the plan sells for less than its assessed value.