Neptune Regional Transmission System

Project Website

Neptune RTS is a multi-phase HVDC submarine network running along the northeast coast of the US from the Mid-Atlantic to Maritime Canada. It was conceived by TR&MC in the mid-1980’s, with actual project development initiated in 1997 after FERC promulgation of rules to enable open transmission access and independent development/ownership.

Neptune RTS was designed to capture surplus gas and hydro generation in the winter peaking Maine and Canadian Maritimes and move it to constrained, summer peaking markets in Boston, Connecticut and New York. Off-peak base load nuclear would be sent north to allow ponding of the large hydro systems. Boundless also determined that while any two independent markets had similar average energy prices, the layering of three or more markets allowed significant arbitrage and hedging opportunities while exploiting very large peak price differentials.

To expand its professional and financial bases, Boundless partnered with four other firms in 1999 to form Atlantic Energy Partners to finalize the project development. Strategic partners New Brunswick Power Corp. and TXU provided development financing. After a successful open season in late 2001, the meltdown of the merchant power and energy project credit market in the wake of Enron’s collapse forced Neptune to seek alternative customers. Boundless created a new Neptune segment – New Jersey to Long Island, and sought out a new customer – Long Island Power Authority (LIPA) – which became the anchor tenant of Neptune’s first leg after extended negotiations and a subsequent RFP that Neptune won.

The 67-mile long, 660 MW HVDC Classic New Jersey to Long Island leg of NeptuneRTS was financed for $650 million in mid-2005 and went into service in June 2007, ahead of schedule and under budget. It operated at over 99% availability in its first year, saving LIPA tens of millions of dollars on purchased power and merit dispatch costs.

Originally viewed by the power industry as too massive a concept, most of the other Neptune interconnection segments conceived by Boundless are now under development by Boundless and others:

  • New Hampshire to Eastern Massachusetts and Cape Cod by Boundless, currently in the New England ISO transmission expansion stakeholder review.
  • Maine to Boston by Boundless’ former AEP partners, also in the NE-ISO expansion process.
  • Nova Scotia to Boston by Nova Scotia Power, in the ISO-NE process.
  • New Jersey to New York City by Boundless’ former AEP partners, in permitting.
  • Newfoundland to New England by Province of Newfoundland/Labrador, in ISO-NE expansion process.