HydroAir™ Turbine for Wave Energy Applications

HydroAir turbine

Oscillating Water Column (OWC) turbine technology is the most successful and extensively studied technology for extracting energy from ocean waves.

OWCs can be located on the shoreline, near-shore or offshore. Incoming surface waves induce an oscillating flow of air within the chamber which, in turn, flows backwards and forwards through an air turbine installed in a duct connecting the chamber to the atmosphere. The turbine converts this reciprocal air movement into electrical energy.

Siemens HydroAir™ Large Scale Power Take Off Unit ‘Sets Sail’

Siemens completes another major milestone for DOE’s one-of-a-kind Marine and Hydrokinetics Program: HydroAir PTO installation and integration on Ocean Energy’s oscillating water column buoy.  The unit is now ready for transportation to US Navy WETS test facility in Hawaii where it will undergo testing in open-sea and grid connected.


The project advances HydroAir’s commercialization efforts in the wave energy market and is a another stepping-stone in the Smart Energy Transition path towards decarbonization and Energy Mix coexistance. 

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OWC turbine technology

The challenge of OWC turbine technology is to achieve satisfactory efficiency over a wide operating range. The airflow not only varies between zero and 100 percent, but also changes direction as it reciprocates. At the same time, the shaft rotation must be maintained in one direction (i.e. clockwise rotation).


Siemens patented  the HydroAir™ turbine which is able to resolve the challenges present in wave energy conversion while offering outstanding performance and reliability. Constructed to withstand the rigors of a marine environment and ambient conditions, it uses a combination of corrosion-resistant stainless steel, aluminum and reinforced composites which also yield to reduced weight. 

HydroAir turbine benefits

HydroAir offers the following benefits when compared to other turbines being used for wave energy capture:


  • Superior energy conversion efficiency
  • One moving part (the rotor)
  • Low rotational speeds resulting in reduced solution complexity
  • Minimized footprint
  • Reduced maintenance
  • Scalable from kW to MW power ratings
  • Wide operating range enables energy conversion of low, medium, and high waves
  • Does not require assisted or auxiliary starting systems
  • Environmentally friendly (GHG emissions-free, low noise emissions)


Simply put, the HydroAir product can be installed anywhere in the world including extreme ambient conditions and can serve various markets, including but not limited to, Oil and Gas, Power Generation, Industrial, and Marine.


Having Siemens as the technology provider for your Wave Energy project gives you the ability and advantage to combine our extensive expertise in the design of high performance turbines with our outstanding Totally Integrated Power solutions which results in a reliable, safe, and efficient power supply.  

Your trusted partner

Put your trust in a partner that knows the energy and power business and technologies inside and out offering flexible, tailored and optimized commercial and technical solutions specifically for your Wave Energy project – from equipment only all the way to full turn-key Power Take-Off (PTO).  

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Questions about HydroAir?