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Quebec ranks second among Canadian provinces for the potential for generating electricity from tidal currents. Hydro-Québec has also analyzed suitable sites in Ungava Bay in recent months, according to what emerges from a document obtained by The duty. But for the moment, no project would be planned.
By using the Act respecting access to documents held by public bodies and the protection of personal information, The duty asked Hydro-Québec to send it any report, study or briefing note produced over the past three years on the potential for the development of wind energy in the marine environment and on the potential for the development of tidal energy in Québec .
In response, the Crown corporation sent four pages taken from a “confidential” document of at least 26 pages, undated, and several passages of which have been redacted. This is the case, for example, for r11 of the 13 “references” listed at the end of the document. Those that have been left visible, however, allow us to understand that it was written after June 2022.
Tidal energy
The document submitted does not include any information on wind energy in the marine environment, but it does address the development of “tidal energy”, which can be produced from tidal or river currents.
It is mentioned that “tidal power” seems to be the most promising technology, since “the turbines can be generally larger at sea and produce electrical powers of more than one megawatt”.
According to a document produced by Hydro-Québec, the “theoretical potential” linked to the tidal current at “eight quality sites” would be around 4200 megawatts. By way of comparison, the Romaine hydroelectric complex has an installed capacity of 1,550 megawatts.
However, this potential is far from the main places of consumption. Hydro-Québec indicates that “the Ungava Bay region has interesting potential because of the strong tides” and presents a map of sites that could prove to be favorable. There are some at the mouth of the Rivière George, the Rivière Arnaud, the Rivière aux Feuilles, but also two at the mouth of the Koksoak River, near Kuujjuaq.
In terms of the “benefits” of this technology, it is emphasized that “tidal turbines do not require complex civil engineering works such as dams”, but also that “the tidal currents are predictable in advance with a large precision”, which makes it possible to “accurately predict” future electricity production.
Hydro-Québec also notes “disadvantages” related to this sector, which may require “an energy storage system”. In the case of Ungava Bay, the need to build “a transmission line of more than 200 km” is also highlighted. Moreover, the cost of tidal energy is higher than that of wind or solar, the technology “is still at the research and development stage” and there is a lack of information on the “environmental impact” of such projects.
No project
By email, the state-owned company adds that it has no development project for this sector for the moment. “We are monitoring its evolution, but the most recent tests, including here in Quebec, have not concluded that this energy source could prove to be more interesting than hydroelectricity, wind power or even solar energy. . »
Hydro-Québec stresses that “developing a transmission network in an environment with extreme weather conditions such as the tundra remains a major challenge” and that the “maintenance” of tidal turbines would be “complex” to say the least.
Full professor in the Department of Physics of the Faculty of Arts and Sciences of the University of Montreal, Normand Mousseau is of the opinion that this sector would face several major challenges, including the remoteness of production sites from places of consumption. “I’m not convinced that this is a very interesting technology,” he concludes.
“In a context of high consumption and potential for energy efficiency, and in a context where onshore wind energies are already established and do not cost so much, it is difficult for more marginal options, often more nested or technically more difficult , to emerge,” explains Pierre-Olivier Pineau, holder of the Chair in Energy Sector Management at HEC Montréal.
“The big advantage of tidal turbines is constant production, but for the moment, in Quebec, with the reservoirs, we have the capacity to absorb more intermittent wind energy without having to rely immediately on regular production inputs,” adds- he. In this context, tidal turbines would not yet be necessary. “They could become so in a few years, especially when populations will be made more sensitive to the deployment of wind farms and will want less visible options. »