With the growing popularity of green investments in renewable energy resources, one that is currently gaining mainstream attention is tidal energy. Recently, the respective US and Canada ocean energy bodies released marine and hydrokinetic (MHK) roadmaps, outlining the benefits and use of ocean energy in North America. As the potential of tidal power will also be explored in a Scottish power station, catching the waves might turn out to be quite important not only for surfers but for potential investors as well.
Even though hydropower in general has received a lot of attention, tidal power in particular is a less popular source of renewable energy than solar or wind power for instance. Tidal power is a “subdivision” of marine or ocean energy which also includes power from ocean waves and ocean temperature differences. In the case of tides, tidal current energy is generated by the movement of water volumes. This type of kinetic energy can be harnessed, usually near shores, and converted into a useful form of electricity.
It is a fact that tides are a result of the gravitational pull of the sun and the moon, together with the rotation of the Earth. Therefore, tidal waves are highly predictable and this characteristic makes them particularly reliable and thus attractive as a green investments opportunity. Unlike solar and wind farms where the energy output more or less depends on variable weather conditions, the energy output of tidal plants can be quite accurately calculated.
According to the US MHK Renewable Energy Roadmap of the Ocean Renewable Energy Coalition(OREC), technologies capturing energy from free-flowing waves, tides and currents, could potentially provide up to ten percent of the US electricity consumption. Similarly, the Canadian Roadmap “Charting the Course – Canada’s Marine Renewable Energy Technology Roadmap” of the Ocean Renewable Energy Group (OREG) outlines the potential of Canada’s marine renewable energy sector to become highly competitive in the global marketplace. In addition, in July 2011, the Government of Nova Scotia announced its plan to create the ‘winning conditions’ for development of an in-stream tidal energy sector that will serve Nova Scotians for generations to come, as reported by the OREG.
The tide is rising on the other side of the Atlantic Ocean as well where the first major tidal power station will be installed in a channel between the two Scottish islands of Islay and Jura, as reported by The Guardian. Estimations are that the underwater turbines will generate enough electricity to power more than 5,000 homes. One of the characteristics of tidal current energy is that it can be accelerated in places where topographical constraints, such as islands and straits exist, which makes the British Isles area particularly appropriate for tidal power generation.
The potential of tidal energy is also being explored on a European level, the recently published European Offshore Renewable Energy Roadmap of the Offshore Renewable Energy Conversion Platforms – Coordination Action (ORECCA) recommends that the EU and its Member States provide targeted funding to accelerate the development of the wave and tidal stream energy sectors.
However, one of the major questions with regards to tidal energy and its benefits for governments and companies considering green investments in the tidal energy sector is the grid connection, as one of the problems is the remoteness of offshore turbines from the grid. Therefore, the ORECCA Roadmap for instance recommends an integrated approach on a European level in order to develop grid, ports and offshore supply chain infrastructure. Canada, however, has a better defined grid strategy, outlined in the OREG Roadmap, as grid-expansion requirements will be identified by 2016and by 2020, utilities will integrate marine renewable energy into long-term planning.
It is quite obvious that there are still obstacles related to tidal energy that need to be overcome. Nevertheless, as governments are investing efforts and funding into this sector, private companies interested in green investments in renewable energy sources are also starting to notice the potential of tidal energy. Despite the relatively early stage of development of tidal power technologies, the predictability of tidal energy implies that it will be a low-risk enterprise, once underwater system sand turbines are in place.
Despite the technical matters that still need to be resolved, tidal power has the potential to become a reliable energy source. Therefore, the sun and moon’s gravity pull creating tides might also turn into a pull for green investments into this renewable energy sector.