Dream of inlet tidal project continues

Dominic Lee’s son, Chris Lee, tells FERC he has taken over as Turnagain Arm Tidal Energy president, wants to see project restarted

Kristen Nelson

Petroleum News

There have been proposals over the years to harness Cook Inlet tidal power and one of those proposals, formerly headed by Dominic Lee, is now being pursued by his son, Chris Lee.

The proposal became public in 2009 when the Federal Energy Regulatory Commission received a preliminary permit application from Little Susitna Construction Co. to partner with Blue Energy Canada Inc. to build a tidal power system in Turnagain Army using structures called tidal fences to harness the inlet’s 30-foot tides using Davis turbines in a $2.5 billion project to generate an average output of 1,200 megawatts.

By 2011, Dominic Lee, president and CEO of Little Susitna Construction, was proposing a different approach, and told FERC in a May 2011 filing that after further engineering study “it was determined that the Davis turbines deployed in tidal fence arrangement … were considered experimental and were not accepted for current use.”

Instead, Lee, filing as Turnagain Army Tidal Energy Corp., said the revised plan was based on a tidal power project in La Rance, France. That project, Lee said, has been in operation since 1966 using a “bulb type of turbine.”

The Cook Inlet proposal called for use of a barrage - a type of low-head diversion dam with gates which can be opened or closed - 1,000 feet long and 100 feet wide some 5 miles from Possession Point near Fire Island.

Lee said bulb-type turbines had been in operation at La Rance for more than 45 years with no recorded breakdowns.

Construction of the project in Cook Inlet was estimated at $760 million, and would produce 240 megawatts of power, he said.

The barrage would be backed by a reservoir 1 mile by 2 miles - a storage tank 20 feet above high tide for water to be used to drive the turbines during slack tide.

Lee said that while tidal power is predictable, it is intermittent because of the slack tide period - hence the storage tank. In Turnagain Arm, he said, the slack tide is short, 15 to 30 minutes, and the reservoir would provide moving water for energy production during the slack tide.

Slot gates would be open during flood tide and closed in ebb and slack tide and during flood tide a pump system would fill the storage tank to 10 feet above high-tide level and during slack tide slot gates would be raised and the turbines would be turned by water coming out of the storage tank.

The reservoir would have a concrete wall surrounded by rock and Lee said the barrage and reservoir would function as an island: fish and sea mammals could swim around it and it might provide habitat for birds and sea mammals.

Chris Lee

Since his father’s death, Chris Lee said, he has taken over duties as president of both Turnagain Arm Tidal Energy Corp. and The Little Susitna Construction Co.

Dominic Lee was not able to raise capital to keep the project moving, Chris Lee said, adding that he joined the project in 2011 to attempt to raise funds for the study phase of the project.

Chris Lee said he did not succeed in raising some $20 million required to get the Turnagain Arm Tidal Energy project to the construction permit phase but was told by the renewable energy divisions of major investment banks that they would have “jumped at the chance to finance” the construction phase, then estimated at $1.6 billion. “The investment banks believed that financing the project was a no-brainer for them, but only if and when the Construction Permit was issued.”

Since bridge funding could not be obtained, the company “subsequently and reluctantly requested” withdrawal of the preliminary application for the Turnagain Arm Tidal Energy Generation project, he said.

Chris Lee had written to FERC to discuss restarting the project.