Let’s unlock the potential of tidal streams & ocean currents. The ocean remains one of the largest yet least exploited renewable energy sources on earth. Ocean energy has the potential to provide a substantial amount of renewable and reliable energy for communities around the world.
The ocean represents a major source of renewable energy. Different technologies employ different strategies to harvest that energy. The main sources of ocean energy are:
Minesto’s technology is developed to efficiently harvest the energy in tidal streams and ocean currents. Tidal streams and ocean currents offer safe, reliable and locally-produced renewable energy. There are several significant advantages over other renewable energy sources:
The large resource of tidal streams and ocean currents can be also exploited with relatively small environmental interaction, thereby offering one of the most lenient methods for large-scale electricity generation.
Tides are generated by the interaction of gravitational forces of the earth, moon, and sun. This relative motion creates tidal currents around the world that contain a tremendous amount of energy. Since the positions of the sun and moon can be predicted with a high level of accuracy, this information can be used to predict the tides’ movement and stream speed anywhere in the world.
Tidal energy is a reliable and predictable source of clean energy compared to other existing renewable energy technologies, encompassing all prerequisites to develop into a significant player in the future renewable energy mix.
Ocean currents are created by regional differences in temperature and salinity and the Coriolis effect due to the rotation of the earth. Ocean currents exist in open oceans and flow continuously in the same direction with low variability. As such, ocean current energy represents a highly reliable non-intermittent energy source.
In addition to the earlier mentioned benefits of tidal and ocean currents, the characteristics of the latter bring further advantages such as:
According to the Intergovernmental Panel on Climate Change (IPCC), given the scale of open ocean currents, there is a promise of significant project scale when technologies harness currents with lower velocity.
Common to both tidal streams and ocean currents is that the vast majority of the resources consists of relatively low-flow currents. First-generation tidal technologies require strong tidal flows with mean peak stream velocities of at least 2.5 m/s and an installation depth between 25 and 50 meters in order to be commercially viable. Research has shown that technologies such as Minesto’s, which can operate in conditions with mean peak velocities from about 1.5 m/s at depths exceeding 50 meters, increase the potential for extracting energy from tidal streams by a factor of 35*.
A summary of available data that Minesto has analysed shows that the technically exploitable potential of tidal streams and ocean currents for Minesto is more than 600 GW installed capacity. This is comparable to the fact that there is currently just under 400 GW of nuclear power capacity installed globally.
The above-mentioned market potential is largely comprised of tidal flow installations. The potential of ocean currents is less studied as there have been few initiatives to approach this resource so far. Only in the Gulf Stream, the US Energy Department estimates that the theoretical recoverable capacity is equivalent to 75 GW, and in Taiwan estimates have been made that 1 percent of the Kuroshio current would equal half of the country’s electricity consumption.
Useful information on ocean energy can be found on the web sites of the trade orgainsations Ocean Energy Europe and RenewableUK.