Mixed energy rafts provide electricity to 1,000 homes every day

Swedish renewable energy company NoviOcean develops a Hybrid Energy Converter (HEC) to simultaneously exploit wave, wind and solar energy, helping to reduce the cost of producing clean electricity, Interesting Engineering reported on October 1. Besides, HEC also generates significantly more electricity than traditional wind farms on the same ocean area.

NoviOcean says that with its modular design and proven components, HEC can be easily manufactured, installed and maintained with minimal environmental impact. “Our machines maximize renewable energy by combining wave, wind and solar energy in a single solution, ensuring electricity production even when there is no sun or wind. Each machine has can provide electricity to more than 1,000 households every day,” Mr. Jan Skjoldhammer, founder and CEO of NoviOcean, shared.

The HEC converter resembles a 38 m long rectangular raft. It lies along the wave direction, with a water-filled cylinder underneath connected to the seabed via a piston rod and cable. Anchors help hold the raft in place.

The machine works like a garden pump. As the raft rises, water is pumped up and flows at high speed to the Pelton turbine, generating electricity. The raft’s wave power capacity is 650 kW. In addition, on the raft there are 6 vertical axis wind turbines generating 300 kW of electricity, combined with solar panels producing 50 – 80 kW of electricity, for a total capacity of about 1 MW.

NoviOcean’s wave power technology has been developed for many years and tested in wave pools and real-world environments. A smaller HEC version is already powering homes on the Swedish island of Svanholmen, proving that the technology works at sea.

One square kilometer of sea can install 15 rafts, generating 15 MW of electricity. In the same area, a traditional wind farm only has a capacity of about 10 MW. When combining these two solutions, they provide a capacity of up to 25 MW, while sharing the costs of marine area and transmission cables.

According to NoviOcean, HEC provides stable energy because the waves can produce electricity for days after the wind calms. Additionally, rafts can be placed close to shore without disturbing the landscape.

NoviOcean’s next step is to launch a large-scale pilot project, collaborating with offshore wind power companies to build mixed farms. Because wave activity in Swedish waters is not strong enough, potential locations include the North and South American coasts.