Innovation provider

Seabased,www.Seabased.com

Contact

Rafael Waters PhD
Head of department - Wave energy converters
Rafael.Waters@Seabased.com
Phone: +46 (0)18 504814

Description

Generator
Seabased's wave power technology utilizes the water motion in waves to directly drive the wave power plants. The active element is a unique directly driven permanent magnet linear generator. The generator is specially designed to take advantage of the slow movement of the waves that is transferred to it via a buoy (point absorber) on the ocean surface.The buoy action is transferred directly to the generator with no intermediate mechanical gearing since the generator is optimized to output high power even at slow speeds.The movement of the waves (about 15 wave cycles/min) causes the translator (corresponding to the swiftly turning rotor of a conventional generator) to move up and down within the stator, thus converting the kinetic energy of the wave to electric energy. Very powerful neodymium-iron-boron magnets are mounted on the translator. They create an alternating magnetic field which penetrates the stator windings. The stroke length of the translator is limited by end stops at the top and bottom.
 
Foundation
The encapsulated generators are anchored to the seabed using a concrete gravity foundation. The foundations are designed and dimensioned according to wave loads and seabed conditions. Seabed preparations in the form of blasting or excavations will not be necessary.
 
Marine Substations
Directly driven systems have a low level of complexity at the mechanical end, but create new demands on the electrical components. The generated electric current from the individual power plants varies both in frequency and amplitude. In order to convert the electricity to a perfect 50/60 Hz alternating current and transmit it to the onshore high voltage grid, Seabased has developed a unique marine electrical system consisting of two different underwater (marine) substations.
 

LVMS/Low Voltage Marine Substation 
Several power plants are connected to one LVMS which rectifies, inverts and transforms the variable alternating current received from the wave power plants.
 

MVMS/Medium Voltage Marine Substation 
In larger wave energy parks groups of LVMS are connected to one MVMS. This substation further transforms the voltage so that the electricity can be transmitted over long distances to the onshore electrical grid. The marine substations are fitted with concrete foundations and their placement on the seabed protects them from physical damage.

Advantages

Wave energy is a renewable, sustainable and free source of energy, and it would have a vast impact on electricity production in the world given that feasible solutions in terms of technology, economy and ecology are provided.

  • Oceans cover about 70 % of the Earth’s surface.

  • The global wave energy potential is at least as big as that of hydropower. Different estimates range from 10,000 to 15,000 TWh per year worldwide.

  • The energy density per meter  wave crest in Sweden is on average 20 times higher than the energy density per square meter of wind, and Sweden is regarded as having a very mild wave climate.

  • The utilization factor for wave power – the ratio of average generated power to the installed power of the power plant – is expected to be as high as 50 % (4,380 h/year).

Innovative aspects (ecologic, social and economic)

Environmental Aspects
Wave energy is  a renewable  energy
-The occupied seabed area from the foundations will inevitably become unavailable for bottom dwelling organisms.
+ There is a strong reason to believe that array installations of submerged wave energy converters will create "safe havens" for marine life, as they become artificial reefs 

Economic Aspects
Seabased  Wave energy is expected to be generated at very competitive costs

Application examples

Scalable system with quick cost recovery
Seabased's system is scalable. A wave energy park built using Seabased's concept can be expanded in stages. Electricity can be generated and delivered to the grid with only a few units installed. Consequently cost recovery can begin long before the entire wave energy park is completed. Seabased's generators have a nominal power of 10-50 kW. The installed power of a medium large wave energy park with 2000 generators, with an average power of 10 kW per generator, is 20 MW with an expected production of 50 GWh per year.Using Seabased's system electrical energy is expected to be generated at very competitive costs with no need for long term subventions or tax reductions. The global potential for wave energy is calculated to be 10 000-15 000 TWh per year. This is comparable to the economic potential for hydro power across the world.

Cost

Downloads

Current stage of development

Already on the market

Intellectual Property Rights

Patent granted

Country of origin

Sweden

Country of application

Year

2001

National Contact Point

Uwe Fortkamp
IVL Svenska Miljöinstitutet AB
Valhallavägen 81
P.O. Box 210 60
114 27 Stockholm

Tel: +46 8 598 56300
Tel: +46 8 598 56390

» uwe.fortkamp@ivl.se
» www.ivl.se