Reliable energy supply system in the point absorber even with high waves

Profile

• What was needed: Energy chain system for safe energy supply within the wave energy converter
• Requirements: Long service life, freedom from maintenance, high resilience
• Area of application: renewable-energy/hydropower industry

The Swedish company CorPower Ocean produces wave energy converters. These are point absorbers in which a floating buoy on the surface absorbs the energy of the sea waves. The buoy is connected to the seabed with a tensioned anchoring system. CorPower's novel "Wavespring Phase Control Technology" causes the systems to oscillate in resonance with the incoming waves, significantly increasing the movement and energy absorption. The system has improved storm survivability and is more compact, lighter and cost-effective compared to conventional point absorbers.

Problem

The harsh marine environment requires a design that must withstand extreme loads during storms. The development team was looking for a reliable energy supply system that would last five years or 20 million activations/deactivations without maintenance in continuous operation. The total service life required was 20 years or 80 million cycles. In addition, the system should have sufficient mechanical strength to withstand the extreme dynamics that build up during the vertical and horizontal movement of 7-metre-high waves. The system also had to be able to cope with vibrations when the waves hit.

Solution

CorPower turned to igus. Our energy supply experts quickly found the right solution: two vertically installed igus e-chains of the E4.1 series, equipped with chainflex servo, power and control cables. The cables are specifically developed for moving applications and achieve an exceptionally long service life in energy chain systems. The system does not require a lot of installation space, is extremely strong, easy to assemble, requires little maintenance and has a considerably lower weight compared to metallic alternatives.