Offshore wind farms, energy islands, ports and proposed “Offshore Power Zones” could together form the foundation of an integrated maritime energy system capable of supporting large-scale vessel electrification across Northern Europe, according to a study by Maersk’s Stillstrom, Baltic Energy Island and the Port of Roenne.
In a whitepaper titled Bornholm Energy Island: Powering Maritime Electrification, the companies state that combining offshore wind generation with port infrastructure and offshore charging concepts could enable ferries, cargo vessels, and service operation vessels (SOVs) to shift away from fossil fuels on a large scale.
The study, which was launched in December last year, looked into how planned offshore wind farms and transmission infrastructure around Energy Island Bornholm in Denmark could act as a model for broader maritime electrification across European shipping corridors.
According to the findings, it is estimated that around 37,000 cargo vessels pass Bornholm each year, consuming approximately 3 million tonnes of marine fuel and emitting around 10 million tonnes of CO₂ annually. Full electrification of this traffic is estimated to require about 17 TWh of electricity per year, potentially replacing roughly EUR 2 billion in fossil fuel imports with domestically generated renewable power.
The whitepaper also introduces the concept of Offshore Power Zones (OPZs), developed by Stillstrom, which involves vessels accessing offshore wind-generated electricity at sea for battery charging or hotel loads. The report sees these zones linked with electrified ports to form an “electric shipping highway” stretching from the English Channel through the North Sea into the Baltic Sea.
According to the study, improving battery technology and strengthening regulatory frameworks are supporting the shift toward maritime electrification, but the availability of reliable and well-located power remains a key constraint.
The report also highlights infrastructure requirements at ports, using the Port of Roenne as an example of how ferry charging, shore power and offshore operations may shape future investment needs. It notes that the port already supports ferry routes, cargo operations, cruise calls and offshore wind activities as a TEN-T Comprehensive port.
The study emphasises that, along with vessel technology, maritime electrification depends on coordinated planning of grid capacity, offshore generation and port infrastructure.