PEMBROKE, Maine — A Utah physicist who is eager to build a $70 million project that would harness the tidal energy that flows into and out of the Pennamaquan River in Pembroke hosted a public site visit Thursday afternoon and a public hearing Thursday evening, answering questions about how a 1,616-foot-long, low dam would be built and operated.
About three dozen area residents and a small contingent of state and federal regulatory officials attended the open-air briefing hosted by Ramez Atiya, the founder of Pennamaquan Tidal Power LLC and the project’s developer. They met informally at a public boat ramp near the open water that stretches between Leighton Neck and Hersey Neck, near the point where the Pennamaquan River flows into Cobscook Bay.
About 50 people attended the 6 p.m. meeting on the project held at the Pembroke Elementary School. A third public meeting is scheduled for 1 p.m. Friday, Oct. 26, at the Maine Department of Environmental Protection’s regional office at 106 Hogan Road in Bangor.
In its 2010 filings with the Federal Energy Regulatory Commission, the company estimates the facility would generate 80,000 megawatt hours of electricity annually. That would represent about eight-tenths of one percent of Maine’s annual energy requirements. Atiya said Thursday afternoon that’s enough electricity to meet the needs of 13,000 homes.
Atiya told both groups Thursday that the concept and practice of tapping the power of tidal ebb and flood cycles have been around 100 years, but are not without problems.
“There are two problems — cost of construction and negative environmental impacts,” Atiya said. “If tidal power is going to go anywhere, you have to address those problems.”
Atiya said the project he is proposing has been engineered to significantly reduce construction costs by using a proprietary “tidal wing” technology. It combines power generation during both the flood and ebb tides with a pumping system so that the tidal levels within the cove would rise and fall to their natural 18.5-foot levels.
“The environmental issues include preservation of intertidal zones,” he said. “Most operating systems do not preserve intertidal zones. By using bulb generators, which look like submarines, we can essentially reproduce the natural ebb and flood of the tides in the basin and fully protect the intertidal zone, which is essential for all the harvesting efforts that occur.”
Atiya also fielded questions about how canoes and other small boats would maneuver through or around the structure and how its 16 small turbines would affect marine life within the river, including migratory alewives. He said the low dam’s design now includes a boat lift that could accommodate vessels as large as 60-by-20-feet.
“We selected bulb transmission turbine technology because it has the lowest fish mortality rate,” he said. “For alewives, the mortality rate is under 2 percent. For elvers, the survival rate would be 99 percent.”
Among those concerned about the impact the project would have on alewives, elvers and other marine species is the Passamaquoddy Tribe, which has relied on migrating alewives as a food source for centuries, according to Tribal Gov. Clayton Cleaves.
Cleaves and other tribal officials met Wednesday afternoon behind closed doors with a three-member FERC delegation that is in Washington County this week to collect public and tribal input on the project. Among those included in Wednesday’s session was Steve Kartalina, a FERC fisheries biologist.
“The tribe showed no support for this project,” Kartalina said Thursday of Atiya’s proposal. “And, beyond this project, we did talk in a larger context about the tribe’s fisheries concerns.”
Atiya was asked by one participant in the outdoor session whether Pembroke residents would enjoy discounted electricity rates in exchange for support for the project, “or will you just sell the electricity to Bangor Hydro, which is Canadian-owned, so that they can turn around and sell it back to the community?”
Atiya said his company has had some preliminary discussion with the Maine Public Utility Commission about rates, but said it would be premature to speculate what rate structure will eventually be agreed upon for the project.
At Thursday evening’s session, which lasted more than two hours, Atiya said he expects the project to generate electricity at 8 cents per kilowatt hour during the first 30 years of its anticipated 120-year life, while the debt service on the project is being paid. For the next 90-plus years, he said, the project generation would cost 2 cents. By comparison, Maine’s electric rates in 2011 averaged 15.4 cents.