Turbowave project

The Basque Country Energy Strategy 2030 sets the challenging target of 10 MW of ocean energy. In this context, the Mutriku Wave Power Plant (MWPP) – that has delivered to the grid 2.7GWh in 2022 – shall remain an active contributor to this target. However, the 16×18.5 KW capacity is provided by Wells type air turbines of first generation, that have been exposed to a marine environment with a high degree of humidity and salinity for the last 13 years, limiting their operating life and subjecting them to frequent maintenance interventions.

Ente Vasco de Energia, after an industry survey, concluded that there was sufficient capacity and manifested interest amongst the industry to design more efficient, robust and reliable turbines and launched a Pre-Commercial Procurement for R&D services – the Turbowave Challenge – to promote the development and testing of new solutions. The challenge encompasses the design, development and demonstration of a cost-efficient, reliable and safe two-directional air turbine system for power production at the MWPP.

A self-rectifying axial-flow impulse air turbine with multi-row guide vanes is our proposed solution for the TurboWave Challenge. The geometry of the rotor blades is a modified version of the classical impulse-type steam turbines. Two fixed multi-row guide vane stators are symmetrically arranged on either side of the rotor. The turbine will be directly connected to a standard electrical generator via a frequency converter (FC) that controls the generator torque at variable speed, following a torque reference.

The turbine and the generator will be specified based on the data representing the optimum “damping” to be provided by the air turbine to the pneumatic chambers of the Mutriku Wave Power Plant (MWPP). The design shall withstand the appropriate aerodynamic, mechanical, and electromagnetic loads, and enable efficient, safe and reliable autonomous operation in the significant wave height range between 0.5 and 4 m.

Kymaner and IDMEC/IST – in the NOVATUM consortium – combine their experience and adopt a modular approach to deliver a complete product, replicable in the 16 chambers of OWC MWPP and scalable for other projects, ranging from 15 kW to 1 MW. The concept developed during Phase I of the project has been validated by EVE as one of the proposals with the best price/quality ratio with regard to the criteria set in the TurboWave Challenge. In Phase II, the target will be to meet the expectation after a thorough laboratory testing sequence of the scaled model of the PTO.