This is the revolutionary screw-shaped turbine that takes advantage of the tides to generate unlimited energy

Renewable energies have long ceased to be the future, and are a fundamental part of our present. In a sector dominated by solar panels and wind turbines, which are increasingly technologically advanced, there is still a need to take advantage of everything the planet can offer to generate energy without polluting, which is a lot. In that sense, the greatest potential is in the sea, through facilities such as the largest tidal energy plant in the world, which will provide cheap electricity to one million homes. taking advantage of the oscillations produced by the tides. In fact, installations that take advantage of waves and tides are also being tested in Spain, in places such as Valencia, the Basque Country or the Canary Islands.

The most recent development in the sector are the Axial Skelter turbines, which the British startup Spiralis Energy wants to start testing in the waters of Alderney, one of the largest islands in the English Channel. One of its great points in favor, in addition to its low cost and great energy efficiency, is its modular and scalable nature. Furthermore, for the most part it is made from plastic waste thanks to 3D printingwhich will allow us to have operational units that are easy to manufacture, repair and recycle into new parts once they have finished their useful life cycle.

With a structure similar to that of other renewable energy generators, such as the revolutionary wooden turbine that provides free light with unlimited energy from rivers, this solution is based on the principle of the Archimedean screw. Thus, Axial Skelter takes advantage of its shape when anchored to floating platforms to generate up to 500 kW of energy with a water velocity of 3.5 m/saccording to data obtained by the company in the first tests.

The force of the waves

For decades, scientists around the world have been looking for ways to take advantage of the movement of sea water, both waves and tides, to generate unlimited, low-cost renewable energy. Many of These systems are still in testing, and pose some drawbackssuch as their impact on underwater flora and fauna, maintenance problems when they are submerged and, in some cases, their poor energy efficiency.

The technicians at Spiralis Energy, a startup based in London, aim to solve all these issues with a design that is as original as it is effective. The starting point is the famous Archimedean screw, but the main novelty is the addition of aerodynamic sections, including a transversal one, which They allow you to generate much more torque (and therefore, more energy) creating low pressure at the top of the turbine.

Another of its main benefits compared to other solutions has to do with its modular nature, with pieces that are assembled on site and can be easily replaced. Large 3D printers are responsible for manufacturing each element with recycled plastic. Once all the parts are obtained, can be transported as a kit along with a generatorwhich remains dry at all times on the surface of the water.

In case any element breaks or fails, the turbine can be disassembled to change it. Once replaced, the broken or defective part can be remelted for new use. This greatly extends the life cycle of this solution, which, of course, requires a floating platform to remain submerged and produce energy thanks to a water movement of 3.5 m/s.

The first tests of the scale prototype of the Axial Skelter are already being carried out off the coast of England, and the results correspond to the data previously obtained thanks to computational fluid dynamics calculations: an energy generation of between 2.2 and 2.5 kW.

Now, those responsible for Spiralis Energy intend to scale their technology to build two functional Axial Skelters, each 20 meters longwith the goal of producing 500 kW in 2025.

Tests in the English Channel

To have accurate data and thoroughly study the feasibility of the system, Spiralis is exploring an agreement with Alderney, an island in the Bailiwick of Guernsey, in the northern part of the English Channel that divides the United Kingdom and France.

Its tidal turbines mounted on floating platforms will not generate energy in the first tests, but will allow study and analyze the flow of tides in the coldest monthsto optimize the design of the Axial Skelter to the maximum before its final entry into service.

The local government of the island is expected to charge a small fee for the use of its waters for these first tests which, if successful, would be followed by the establishment of a company office in the region and the beginning of the supply of electricity to the local grid at a reduced price. In the future, it is also planned to carry out tests with new prototypes in the European Marine Energy Center in Orkney.

According to the company’s brief website, its solution would have the lowest LCOE (normalized cost of energy) in the world compared to other similar solutions. This data is obtained by adding the costs of an energy generation asset over its entire life period, although at the moment Spiralis has not revealed the exact data. Also, always according to the British starup, Axial Skelter would have the highest energy density per surface area usedso its potential in the tidal sector is immense.