Onshore Power Supply (OPS)

Onshore Power Supply (OPS), also known as shore-to-ship power, cold ironing, shore power or Alternative Maritime Power (AMP), enables vessels to switch off their onboard diesel generators and connect to the local electricity grid while berthed.

By supplying electrical power from the shore, OPS reduces emissions, noise and fuel consumption, helping ports, terminals and vessel operators improve environmental performance while supporting wider port electrification strategies.

Cold ironing is another term for Onshore Power Supply (OPS). It refers to the process of providing electrical power from the shore to a vessel while it is alongside, allowing auxiliary engines to be shut down.

The term originated when steam-powered ships allowed their iron engines to cool while connected to an external power source. Today, cold ironing is widely used to describe modern shore power systems.

These terms are often used interchangeably.

• Onshore Power Supply (OPS) is the most commonly used term in Europe.
• Shore power is a general industry term.
• Shore-to-ship power describes the physical transfer of electricity from shore to vessel.
• Alternative Maritime Power (AMP) is widely used in North America.
• Cold ironing is the traditional term still commonly used throughout the maritime industry.

Although the terminology differs, they all refer to supplying electrical power from the shore to vessels while alongside.

Ports are investing in OPS as part of wider port electrification programmes to reduce emissions, improve local air quality and prepare for future environmental regulations.

Shore power can also help ports:

• Support customers’ decarbonisation objectives.
• Improve air quality for neighbouring communities.
• Reduce vessel noise while alongside.
• Enhance competitiveness by attracting compatible vessels.
• Prepare for future legislation and international environmental standards.
• Demonstrate ESG and sustainability commitments.
• Reduced fuel costs.

Yes. Many ports can introduce OPS without major redevelopment.

A feasibility study can determine:

• Existing electrical capacity.
• Additional power requirements.
• Grid reinforcement needs.
• Suitable berth locations.
• Phased implementation options.
• Future expansion opportunities.

Retrofitting allows ports to introduce shore power as demand grows rather than delivering all infrastructure in a single phase. Actemium specialises in the containerised solution which reduces the impacts to the ports operations and business as usual.

Every port is different. Successful projects require careful consideration of existing electrical infrastructure, available grid capacity, vessel power requirements and future growth.

Common challenges include:

• Grid connection capacity.
• High-voltage electrical infrastructure.
• Existing port operations.
• Multiple vessel types and power demands.
• Space constraints.
• Future expansion.
• Integration with existing assets.
• Regulatory compliance.

Working with an experienced engineering partner early in the project helps reduce technical and commercial risk.

Delivering an effective shore power solution requires much more than installing connection equipment.

A typical project may include:

• Feasibility studies.
• Business case development.
• Front-End Engineering Design (FEED).
• Grid connection studies.
• High-voltage and low-voltage electrical design.
• Primary and secondary substations.
• Power distribution.
• Protection and control systems.
• Automation and monitoring.
• Civil engineering.
• Installation and commissioning.
• Maintenance and lifecycle support.

Actemium UK provides end-to-end engineering expertise, supporting customers from advice to maintenance and everything in between.

OPS is often one of the first and most significant steps in a wider port electrification strategy.

As ports electrify cranes, cargo handling equipment, vehicles and future hydrogen or battery-powered operations, electrical demand increases significantly. A well-planned OPS project can form part of a wider electrical infrastructure strategy that prepares ports for long-term growth and the transition to lower-carbon operations.

Actemium UK combines specialist expertise in electrical engineering, automation, industrial power systems and complex infrastructure delivery to help ports successfully deliver Onshore Power Supply projects.

Rather than supplying individual components, we work alongside customers throughout the project lifecycle, from early feasibility studies and Front-End Engineering Design (FEED) through to detailed design, construction, commissioning, maintenance and long-term asset support.

Our bespoke engineering solutions are built around your operational requirements, helping you reduce project risk, modernise critical infrastructure and support the transition towards cleaner, more resilient ports. We specialise in the containerised OPS system in a box, minimal disruption to ports operations and the quick return to operational outputs.