Tidal barrage projects to require conventional license


Through a letter issued to Tidewater Associates on November 3, FERC has determined that tidal barrage projects do not qualify for a hydrokinetic pilot license but will have to obtain a license as conventional hydropower. This type of technology requires construction of a dam, which is the reason for such a decision by FERC.A tidal barrage project involves building a barrage (dam) across a body of water such as a bay to retain water during tidal events. As tidal water flows into and out of the barrage, the reversible turbines installed in the barrage wall generate electricity. Tidewater is proposing to install a tidal project at the entrance to Half-Moon Cove in Washington County, Maine between Eastport and Perry. The dam would be 1,210 ft long with a maximum depth and elevation of 40 and 27 feet below mean sea level. It is expected that the three generating units will have a total installed capacity of 13.5 MW.Tidewater is also exploring the possibility of adding hydrokinetic component to the project. Due to this combination of conventional and hydrokinetic technology, a combination of ILP and pilot licensing process was requested at FERC. However, FERC has determined that the pre-application document filed by Tidewater did not contain adequate information to initiate ILP, the Commission’s licensing process for conventional hydropower. For the hydrokinetic component, a pilot-license would be required. Tidewater has until April of next year to submit either a pre-application document for conventional hydropower or an application for hydrokinetic pilot license.Although there is an increasing interest, there are no commercial tidal energy projects in the United States yet.

How Tidal Power Works?
  •  As tide comes in, sea water passes through barrage to landward side
  • At high tide, sluice gates shut, trapping water in estuary or basin
  • When tide recedes on sea-side of barrage, sluice gates open water flows through barrage, driving turbines and generating power
  • Power can be generated in both directions, but this can affect efficiency and economics of project

Source: BBC News