Jeju's Renewable Energy Front: Harnessing Ocean Waves and Wind for Green Hydrogen

On September 14, a vessel departed from Jeju's Gosan Port and, after about 20 minutes at sea, revealed a concrete structure painted in black and red. This is the wave power test facility operated by the Ship and Ocean Plant Research Institute. Although a representative from the institute noted that the sea was relatively calm that day, the boat continued to sway with the waves.

As renewable energy installations increase in Jeju, the technology for storing and reliably operating electricity is becoming increasingly important. At the wave power test facility, experiments are underway to convert electricity generated from marine energy into hydrogen, while the Doosan Wind Power Center is using artificial intelligence (AI) to detect anomalies in wind turbines.
 
The wave power test facility, located in the middle of the ocean, is Asia's first 5 MW grid-connected marine energy demonstration facility, covering an area of approximately 1.04 million square meters. It features five mooring sites in waters ranging from 15 to 60 meters deep, with underwater cables and connectors installed. This allows for the testing of performance and safety of wave and wind power equipment developed externally, connected to the power grid.

The concrete structure built at sea weighs about 10,000 tons. It was installed using a caisson method, where the structure is moved from land to sea and secured to the seabed by its own weight. Since its establishment around 2016, it has withstood over ten typhoons without any reported issues.

On one side of the facility, a silver pipe draws seawater, while on the opposite side, underwater cables connect the mooring sites to the onshore power grid. The electricity generated by the demonstration facility can either be sent to land via the underwater cables or converted into hydrogen within the structure.

This facility is also conducting experiments to produce hydrogen using electricity generated from wave and wind power. It marks the first domestic attempt to produce green hydrogen directly from marine energy. Inside the structure, there is a 100 kW electrolysis system and power and communication control devices.

Unlike on land, it is challenging to supply fresh water needed for electrolysis at sea. Therefore, seawater is desalinated for hydrogen production, and seawater is also used to cool the equipment. The unmanned structure is monitored and controlled remotely from an onshore control room and a research institute in Daejeon.

To date, over 720 hours of hydrogen production testing have been conducted. The institute is also installing hydrogen storage systems and fuel cells to test technology that converts stored hydrogen back into electricity for use within the facility.

Converting electricity into hydrogen results in an energy loss of about 60% during the process. However, hydrogen can be stored for long periods and transported via pipelines or ships. This is particularly useful in areas where it is difficult to build transmission networks from the open sea to land or where direct electric alternatives to ship fuel are not feasible.

The institute has assessed that South Korea's marine green hydrogen technology lags behind Europe. The equipment installed at the Jeju test facility is a 100 kW fixed system. The institute aims to verify floating hydrogen production technology by 2031 and expand to megawatt-scale production.

Kim Kyung-hwan, head of the Eco-Friendly Marine Development Research Division at the Ship and Ocean Plant Research Institute, stated, "To produce hydrogen at sea, we need to desalinate seawater while withstanding salinity and typhoons, and operate the equipment remotely. We are developing technology to perform all processes from hydrogen production to storage and utilization at sea."
 
While experiments to convert electricity generated at sea into hydrogen are ongoing, efforts are also being made on land to reduce downtime for wind turbines. At the Doosan Wind Power Center on Ora-nam-ro in Jeju City, the operational status of 80 wind turbines installed at 11 power plants nationwide is monitored remotely 24/7.

The center's monitor displays real-time output and operational status of wind turbines scattered across Jeju and Jeollanam-do. Each turbine generates over 300 data points. Staff analyze various signals, including temperature and vibration, to assess the likelihood of malfunctions and relay necessary maintenance information to the field.

Wind turbines are often installed in mountainous or offshore locations, making immediate access difficult in the event of a malfunction. Particularly at sea, strong waves and winds can prevent workers from reaching the site. Large components can weigh between 10 to 20 tons, requiring heavy cranes and specialized vessels for replacement. This makes detecting anomalies before a turbine fails crucial.

Doosan Enerbility utilizes its self-developed remote operation system, WindLink, to collect and analyze turbine data. Using AI and algorithms, it identifies anomalies from existing operational data and requests inspections or parts replacements from field staff based on the analysis.

A representative from Doosan Enerbility noted, "We receive over 300 data points in real-time from each turbine. We analyze the data remotely to determine what maintenance is needed and request action in the field."

Doosan Enerbility has supplied 98 wind turbines in South Korea, totaling 349.5 MW. The Wind Power Center manages 80 of these turbines. In Jeju, the center monitors the operational status of 37 out of 40 turbines supplied by Doosan. Among the 30 personnel working at the center and various power plants, 24 are from Jeju.

The operational effectiveness of the Wind Power Center has not yet been quantified. The center has not been open long enough to gather sufficient data for a before-and-after comparison. Doosan Enerbility aims to reduce inefficiencies in maintenance and repair processes by 20% using AI and digital technology.

Choi In-ho, head of the Doosan Wind Power Center, stated, "It is still early to present numerical improvements in operational efficiency due to insufficient data comparing before and after the center's opening. The primary goal of maintenance is to prevent failures and minimize downtime for turbines."