It will be at least next summer before another attempt is made to tame the Bay of Fundy to produce tidal power.
“We’re continuing to upgrade the next turbine we’ll deploy,” says Stacey Pineau, an Emera employee and spokesperson for Cape Sharp Tidal near Parrsboro. Cape Sharp is a joint venture between Emera and OpenHydro, a French-owned company headquartered in Ireland.
“The focus right now is on improving efficiency and reliability. With the onset of winter, the next marine operations will take place when the weather is more predictable. That likely means a deployment in the summer 2018,” says Pineau.
A year ago this month, Cape Sharp placed a 2.0 megawatt turbine in the Minas Passage. It made history by successfully transforming tidal energy from the Bay of Fundy into electricity for the provincial grid. It was the first time this turbine design had been deployed in the world. In 2009, a smaller, less sturdy version was destroyed by Fundy tides less than three weeks after being deployed.
Turbine 2.0 performed much better but it wasn’t yielding “optimum” results, according to the company. Last June, OpenHydro used a barge to lift and retrieve the machine to make upgrades to its turbine control centre (TCC).
In an August newsletter, Cape Sharp describes the turbine control centre as an “underwater substation.” One function is to transform the raw power from the generator into grid-compatible AC power, something the company has indicated needs more work. The company has until the end of December to provide the Utility and Review Board with data on how much electricity the turbine generated during the first three months of 2017. It stopped producing the end of March but a tangled mooring line delayed its retrieval.
So far, all that has been reported is 5.4 Mwh (Megawatt hours) produced during the commissioning phase in November and December — roughly enough electricity to supply 330 homes for an afternoon.
The TCC also sends operational and environmental sensor data to shore in real-time through a subsea cable. Imaging sonar technology and hydrophones (passive acoustic devices built in Great Village, NS) watch and listen for marine wildlife near the turbine which has 10 blades circling a doughnut hole centre.
The massive turbine weighs 1,000 tonnes and stretches about five storeys from its base on the ocean floor. The harsh environment of the Bay of Fundy has rendered a video camera useless and required extra monitoring gear to track sea creatures and comply with regulations around providing 24/7 information about environmental conditions.
Since the turbine was pulled up this spring, detailed inspections of the unit have been taking place in Saint John, New Brunswick.
A second turbine built in Pictou is still awaiting deployment. So far, the two companies involved in the tidal demonstration project say they have spent approximately $33 million here. The federal and Nova Scotia governments have contributed $15 million for research, studies and equipment at the Fundy Ocean Research Centre (FORCE) outside Parrsboro where a handful of test berths are located.
Because of the big money and challenges involved in this real-life trial, other tidal energy companies continue to wait and see how the Cape Sharp experiment fares before jumping in with their own turbine prototypes.