OldBlackDog
Well-Known Member
OPINION: New turbines just as lethal as Annapolis turbines
Much more needs to be said and written about the testing of tidal stream turbines in Minas Passage.
Graham Daborn, emeritus professor at Acadia University, wrote an Opinions article under this heading (Oct. 15), but without the “more”.
Unfortunately much of what has been said and written comes from the proponents of tidal power. And they have obscured the facts about what the physical properties of their machines can do to living organisms.
People living around Minas Basin still talk about what happened when the first turbine was installed at the FORCE (Fundy Ocean Research Center for Energy) experimental site in 2009.
Two humpback whales suddenly showed up on Minas Basin beaches with large gashes in their bodies. That turbine suddenly stopped working and when it was lifted in 2010 blades were broken. What broke them?
Large whales can move quickly. Nothing prevents them from leaving the southern Bay of Fundy in the morning to forage in Minas Passage that afternoon.
There was a Clean Current tidal turbine in B.C., but it was suddenly removed. Rumour among turbine engineers is that it killed a killer whale. Recently the deployment of turbines in Puget Sound was stopped because of concern for killer whales. (Google: Orca Conservancy)
Lobsters are very abundant in Minas Passage, as they migrate into and out of Minas Basin, where summer temperatures are 6-8 C higher than they are in the Bay of Fundy. Their behaviour has evolved from the fact that lobster larvae grow faster in warm water. Faster growth means higher survival.
Lobster fishers in Minas Passage benefit from this and where lobster catches in other areas drop off after the first few weeks of the season, Minas Passage catches remain consistently high. Do we want to upset this benefit to Nova Scotia? They have already lost two square kilometres of lobster bottom to the FORCE site.
Fact: There was a statement that the Cape Sharp tidal turbine is “nothing like the Annapolis turbine.”
Nothing could be further from the truth. Both are axial-flow, hydraulic lift turbines. Yes, the Annapolis turbine rotates 50 r.p.m., but it only has four blades. The Cape Sharp turbine will rotate at 10 r.p.m., but because it has ten blades, the distance between the rotating blades (water length) is almost the same (3.4 metres vs. four metres), making it as lethal as Annapolis.
Annapolis only operates about 11 hours a day on ebb tide. The Cape Sharp turbine will operate on both ebb and flood tide (23 hours a day), making it doubly dangerous.
Daborn states the Cape Sharp permits are for testing purposes only. Annapolis was installed as a test turbine and 31 years later it is still spinning, still killing fish (five sturgeon and counting this year). There never was an environmental assessment. Cape Sharp can keep putting in 2-megawatt turbines for years without triggering an assessment.
Michael Dadswell is a retired professor at Acadia University. He lives in Chester.
Much more needs to be said and written about the testing of tidal stream turbines in Minas Passage.
Graham Daborn, emeritus professor at Acadia University, wrote an Opinions article under this heading (Oct. 15), but without the “more”.
Unfortunately much of what has been said and written comes from the proponents of tidal power. And they have obscured the facts about what the physical properties of their machines can do to living organisms.
People living around Minas Basin still talk about what happened when the first turbine was installed at the FORCE (Fundy Ocean Research Center for Energy) experimental site in 2009.
Two humpback whales suddenly showed up on Minas Basin beaches with large gashes in their bodies. That turbine suddenly stopped working and when it was lifted in 2010 blades were broken. What broke them?
Large whales can move quickly. Nothing prevents them from leaving the southern Bay of Fundy in the morning to forage in Minas Passage that afternoon.
There was a Clean Current tidal turbine in B.C., but it was suddenly removed. Rumour among turbine engineers is that it killed a killer whale. Recently the deployment of turbines in Puget Sound was stopped because of concern for killer whales. (Google: Orca Conservancy)
Lobsters are very abundant in Minas Passage, as they migrate into and out of Minas Basin, where summer temperatures are 6-8 C higher than they are in the Bay of Fundy. Their behaviour has evolved from the fact that lobster larvae grow faster in warm water. Faster growth means higher survival.
Lobster fishers in Minas Passage benefit from this and where lobster catches in other areas drop off after the first few weeks of the season, Minas Passage catches remain consistently high. Do we want to upset this benefit to Nova Scotia? They have already lost two square kilometres of lobster bottom to the FORCE site.
Fact: There was a statement that the Cape Sharp tidal turbine is “nothing like the Annapolis turbine.”
Nothing could be further from the truth. Both are axial-flow, hydraulic lift turbines. Yes, the Annapolis turbine rotates 50 r.p.m., but it only has four blades. The Cape Sharp turbine will rotate at 10 r.p.m., but because it has ten blades, the distance between the rotating blades (water length) is almost the same (3.4 metres vs. four metres), making it as lethal as Annapolis.
Annapolis only operates about 11 hours a day on ebb tide. The Cape Sharp turbine will operate on both ebb and flood tide (23 hours a day), making it doubly dangerous.
Daborn states the Cape Sharp permits are for testing purposes only. Annapolis was installed as a test turbine and 31 years later it is still spinning, still killing fish (five sturgeon and counting this year). There never was an environmental assessment. Cape Sharp can keep putting in 2-megawatt turbines for years without triggering an assessment.
Michael Dadswell is a retired professor at Acadia University. He lives in Chester.