Decarbonisation advisory for existing vessels: from assessment to implementation

For shipowners considering decarbonisation, the available technologies are only part of the decision. Each option must fit the vessel’s operation, technical limitations and remaining service life, while delivering benefits that justify the investment.

GLO Marine provides decarbonisation advisory to help owners assess the options and develop a practical upgrade plan. Supported by multidisciplinary engineering expertise, our recommendations account for both potential savings and the requirements for implementation onboard.

Understand the vessel’s energy use

Our decarbonisation advisory starts with the vessel’s operating profile. Machinery demand, generator loading, fuel consumption, time in port and trading patterns help establish where improvements may be possible.

We consider these findings alongside the condition of existing systems, available space and upcoming docking opportunities. Where operational data is incomplete, onboard surveys and measurements provide a more reliable baseline for comparing solutions.

Identify suitable upgrade options

The appropriate scope may range from improvements to existing equipment to substantial changes in propulsion, power generation or fuel arrangements.

GLO Marine’s decarbonisation advisory considers both major retrofits and targeted efficiency measures, selecting options for further assessment according to the vessel’s requirements.

Major retrofit and conversion options

• Wind-assisted propulsion systems (WAPS): Reviewing wind conditions along trading routes, deck arrangements, structural foundations, stability and operational clearances.
• Air lubrication systems (ALS): Assessing hull modifications, compressors, piping and electrical demand to determine net energy-saving potential.
• Battery and hybrid systems: Evaluating operating modes, load profiles and integration with existing generators and power distribution.
• Shore power: Defining onboard electrical requirements against connection opportunities at the vessel’s intended ports.
• Alternative-fuel conversions: Examining engine compatibility, fuel storage, supply systems and safety provisions, with emissions benefits evaluated across the proposed fuel’s lifecycle.
• Waste heat recovery: Assessing opportunities to use available heat for onboard heating or electrical generation.
• Onboard carbon capture: Reviewing equipment integration, energy consumption, CO₂ treatment, storage and offloading requirements to establish net emissions-reduction potential.

Targeted energy-efficiency improvements

• VFD retrofits: Adjusting pump and fan speeds to match variable demand.
• Pump modernisation: Reviewing equipment sizing, duty points and losses from throttling or bypass arrangements.
• Control improvements: Refining sensors, setpoints and operating sequences so equipment responds to actual requirements.
• Power management optimisation: Assessing generator loading and operating combinations while maintaining required redundancy.
• Propeller and propulsion improvements: Evaluating propeller modifications and energy-saving devices against typical speeds and loading conditions.
• Hull-performance improvements: Reviewing coatings and hull and propeller maintenance measures to reduce resistance.
• HVAC and refrigeration upgrades: Assessing cooling demand, equipment efficiency and control strategies.
• Lighting upgrades: Identifying suitable applications for LED replacements and automatic controls.

Each measure is screened for technical suitability and potential value before progressing to detailed engineering.

Compare benefits and integration requirements

Decarbonisation advisory must consider how proposed measures affect the vessel as a whole. Expected savings need to be weighed against investment costs, maintenance requirements, installation constraints and operational disruption.

GLO Marine assesses the implications for structure, stability, piping, electrical systems and automation. We also examine the interaction between upgrades. Reducing auxiliary consumption, for example, changes the demand profile used to assess a battery installation.

Savings estimates account for these dependencies and any additional energy consumed by new equipment. The projected savings from individual technologies cannot simply be added together.

This provides a clearer basis for deciding which measures to prioritise, which to combine and when to install them.

Develop a practical implementation plan

The outcome of GLO Marine’s decarbonisation advisory is a vessel-specific plan covering:

• Recommended measures and anticipated benefits.
• Preliminary costs and further engineering requirements.
• Outstanding information needed to confirm feasibility.
• Class and approval considerations.
• Procurement, installation and docking dependencies.
• Performance verification requirements.

Our technology recommendations remain impartial and reflect the vessel type, operating profile and owner’s objectives.

Once the scope is agreed, GLO Marine can carry the selected upgrades through engineering, procurement, installation and commissioning under one project management team. Planning performance verification from the outset allows the completed installation to be assessed against the agreed objectives.

By connecting decarbonisation advisory with project delivery, we help owners make informed investment decisions and put suitable upgrades into operation.