Neptune Regional System has closed its 660MW power transmission line for over three hours, leading to a wholesale electricity prices hike in Long Island, US.

Neptune planning VP Christopher Hocker said the 65-mile subsea transmission line resumed service after conduit was repaired due to a leak in the valve cooling system.

In Long Island, on-peak power jumped to average $337.79 per MWh on 7 February from $205.93, reports Bloomberg that compiled data from the New York Independent System Operator.

The power line, which brings power to Long Island from New Jersey, could power about 600,000 homes. It supplies over 20% of Long Island’s typical electricity demand, according to Neptune.

Neptune operates under a long-term agreement with the Long Island Power Authority, and is managed by Connecticut-based PowerBridge, an energy and infrastructure projects developer and operator.