Spain Tests a 42-Meter Buoy Designed to Harness Wave Energy

Wave Energy Buoy MARMOK-A-5 Enters Testing Phase

According to НВ — Техно: On May 23, a report was released detailing the testing of the MARMOK-A-5 wave energy converter, currently undergoing trials off Spain’s northern coast at the BiMEP platform. The device stands 140 feet (42 meters) tall and weighs 160 tons. Anchored at a depth of nearly 90 meters, it operates on the oscillating water column principle and can deliver a peak power output of 30 kW. This project is part of the EuropeWave program, which has a total budget of 20 million euros.

Design and Operation of the Device

MARMOK-A-5 resembles a massive cylindrical structure, with only a small portion protruding above the water’s surface. The remaining 160-ton bulk of the buoy remains submerged. Inside, a hollow chamber allows seawater to enter. As waves rock the buoy, the water level inside the chamber moves up and down like a piston, compressing and decompressing the air trapped in the upper section. This action drives a turbine, generating electricity that is transmitted to shore via an underwater cable.

An earlier version of the device operated successfully at sea from 2016, enduring winter conditions. The current model features intelligent control systems, adjustable turbine blade angles, and onboard batteries. The prototype's peak capacity is 30 kW. Led by Borja de Miguel (IDOM), the project is part of the broader EuropeWave initiative, which aims to advance wave energy generation technologies across Europe.

The MARMOK-A-5 wave energy buoy trials reflect the growing interest in renewable energy sources, particularly wave power, as an alternative to conventional electricity generation. The development of such technologies could significantly reduce carbon emissions and decrease reliance on fossil fuels. Successful testing of the MARMOK-A-5 may also unlock new opportunities for commercial wave energy deployment in Europe, marking a key step toward the region's energy transition.