Case 41: Electricity produced by sea currents

The market

It is estimated that $ 190 billion in investments in new energy sources in the next two decades will be devoted to technologies linked to tides, marine currents or waves. The International Energy Agency believes that the tide energy could produce 200 TW per year, while the energy of the waves could produce 8,000 TW. Production could reach, according to certain estimates, 80,000 TW. In the space of a decade, the United States could produce 10 GW of Houlomotor energy and 3 GW of tide energy. Once captured, potential in the United States would be enough to produce 6 % of electricity demand in the United States. However, most of the technological development in the area of ​​oceans energy has its origin in Europe, supported by the ceiling and exchange policies which make all renewable energies an emerging sector. The most promising regions for the energy of the waves are Alaska, the Northern Sea, Northeast of Canada, the eastern Cape of South Africa, South Brazil and Argentina, Japan, Indonesia and South Australia. The regions with high potential for exploitation of the tide energy include the Strait of Bering, northeast of Brazil, the large lakes of North America, the northern Cap of Norway to Russia, from the Korean peninsula to The China Sea, Northwest Australia and New Zealand. The only country to have successfully implemented a tide energy system is France. The Rance power plant in Brittany has produced 240 MW of electricity since its construction in 1966 each year. The United Kingdom is a pioneer in terms of energy energy in the European Marine Energy Center (EMEC). The United States was the pioneers in Hawaii of another form of energy based on the oceans: the exploitation of temperature differences, known as the thermal energy conversion of the oceans (OTEC). A vast portfolio of companies has embarked on the design and construction of equipment that makes it possible to meet the considerable environmental and climatological challenges that these energy production facilities must meet. Ocean Power Delivery (Scotland) joined Vattenfall (Sweden), Enersis (Portugal), E.ON (Germany). Theoretically, the various devices could extract 40 MW of power per kilometer of coastal when the waves are low (1 meter) and 1,000 mW per kilometer of coast when the waves reach 5 meters.

Innovation

Water is a liquid and therefore the energy of the waves and currents contains about 1,000 times more kinetic energy than the wind. This allows the smallest devices to produce more energy. In addition, sea waves are produced 24 hours a day. The innovations in mechanical design and maintenance on the one hand, and the reduction of the environmental impact on the other hand, represent a challenge for engineers because waves and currents have very high strength at low speed. Electricity production requires high speed. A second limiting factor for engineers is difficult weather conditions. Any floating or submerged device attached to the bottom of the sea by cables and chains must withstand storms and even tsunamis. Tim Finnigan, auxiliary professor at the University of Sydney, a graduate in environmental fluid dynamics, observed how giant Varech moves to the rhythm of currents and waves. He realized that the giant Varech (Laminaria SPP) has a growth of half a meter per day, sometimes reaching up to 80 meters. Better yet, the Varech moves with the currents which bring a richness in nutrients. When a storm or a tsunami strikes, these immense underwater forests collapse on the bottom of the ocean. Mr. Finnigan studies the dynamics of the fluids of Varech movements and converts them into mathematical models which serve as design parameters for an electric generator. Its approach makes it possible to take up both the challenges of speed and mooring. Its design is based on geometry borrowed from proven systems in nature. This is one of the fundamental principles of the blue economy. In addition, its patented biowave generators move in the oceanic ecosystem as if it were Varech. Its devices do not have rotation movements that resemble fans or mills, or create dams that stop the flow of nutrients that cause siltation, thus posing no known danger for aquatic life. The most important feature may be that Biowave moves with the flow of currents and waves. Instead of strengthening mechanics against excessive forces created by inevitable storms, Professor Finnigan managed to adopt the ultimate security system: when a tsunami strikes the region, biowave remains flat on the background as the varech . While the energy of waves and marine currents has long been considered non -profitable, because it cannot resist the hostile marine environment, Professor Finnigan learned his lessons on the ground and borrowed the most intelligence Large species of ocean algae

The first cash flow

Mr. Finnigan then created the company Biopower, based in Sydney, and completed his knowledge on how the Varech moves with observations and geometric models of the way the sharks, the tuna and the mackerel are propelled. This resulted in a portfolio of patents deposited under the Biowave and Biostream brands. Projects are being developed in Australia, Spain and the United States to transform this approach to capturing waves and currents into a technological breakthrough of the most relevant on the commercial level. The system being modular, it makes it possible to install units of 250, 500 and 1,000 MW on a farm, near the shore, without visual impact, without submarine stress on the ecosystem and without excessive fixing at the seabed.

The opportunity

Market development is just beginning. The propensity to invest in offshore facilities is large and compared to the complexity of wind farms, Biopower has simplicity and security. The most obvious commercial application is to make the small island communities self -sufficient by placing biowave installations in front of the site which requires a demand for electricity. As the supply is guaranteed and it is as reliable as the orbit of the Moon and the law of gravity, this source of energy could also provide basic energy. The energy supply of Biowave and Biostream is so certain that an installation of a dozen units withdraw a population of 10,000 people from the network and that no one will even have to install light switches. Energy supply will have evolved by a rarity ensured by polluting diesel generators to an invisible, odorless and permanent flow.