Maine regulators approve tidal energy PPA concept

Yesterday, the Maine Public Utilities Commission approved the terms of a power purchase agreement between three large utilities and a hydrokinetic tidal power project in Maine waters.

Low tide at Preble Cove, Great Cranberry Island, Maine.

Hydrokinetic energy projects produce electricity from moving water like tides, waves, ocean currents, or rivers, typically without dams.  As I noted yesterday, a 2010 Maine law required the PUC to conduct a competitive process to solicit proposals for long-term contracts for offshore wind and tidal projects.  The PUC received multiple submissions in response.  Commission staff have been negotiating with some of the bidders, and yesterday approved a proposal by Ocean Renewable Power Co. to sell the output of a small tidal project in Cobscook Bay to Maine's three largest utilities.

Under the terms approved the Commission, ORPC will receive a 20-year contract with utilities Central Maine Power Co., Bangor Hydro-Electric Co., and Maine Public Service Co. to sell the output of its underwater tidal power generation units.  ORPC plans to install the first of these units in Cobscook Bay this summer, and plans to expand its pilot project to include sites off Lubec and Eastport in the next 4 years.

While many of the terms of the resulting contract remain to be worked out, one piece appears firm: the price.  Utilities will pay 21.5 cents per kilowatt-hour for the tide-generated electricity in the first year; this base price of 21.5 cents will escalate at 2% per year, reaching a price of about 39 cents per kWh in the final contract year.  (By way of comparison, the Cape Wind offshore wind PPA approved in Massachusetts starts at 18.7 cents per kWh, with a 3.5% annual escalator over its 15 year term.  The ORPC initial rate is over twice the average rate currently paid by Maine utility customers on "standard offer" default service, or about 5 times higher than the current wholesale price in the New England market.)

For ORPC, the contract is a significant boon.  Securing a 20-year power purchase agreement should greatly assist the developer in securing financing for the project.  This project is designed as a demonstration or pilot project, but may be able to serve as a proof that ORPC's technology and installation systems will work on a larger scale.

For ratepayers, the volume of the contract is relatively low - as licensed by FERC, the Cobscook Project has a maximum capacity of 300 kW - meaning that its above-market costs will be diluted in the much larger pool of power consumed in Maine.  Nevertheless, if the contract volume grows as ORPC builds more of its scalable tidal generation units, those costs will become less and less dilute.  On the other hand, the contract itself - which still needs approval by the PUC once it is finally negotiated - may include other products or commodities such as capacity or renewable energy credits (RECs).  Developers typically prefer securing long-term contracts for as many commodities as possible, which helps solidify their future revenues, but it can make it harder to compare two contracts.

Many tidal projects today face high capital costs, let alone research and development expenses, but many believe that their fuel-free nature will ultimately enable tidal power to have a low fundamental cost of production of electricity in the future.  ORPC's project may shed some light on how that belief fares in the Gulf of Maine.