Green Hydrogen Feasibility at Portsmouth Port Paves Way for Tugboat Decarbonization

You might think it’s a wild idea, but a new UK government-backed feasibility study shows naval and commercial tugs at Portsmouth Port could run on green hydrogen—and still save money over their lifetime. The study, led by Serco, Rux Energy and Associated British Ports (ABP), lays out a clear roadmap for a zero-emission tug fleet—if the right policies and hydrogen infrastructure investments come through.

Here’s the kicker: a 4.0 MW electrolyser fed by on-site solar or wind power can crank out enough H₂ each day to keep several tugs moving. Even better, Rux Energy has proven its metal-organic framework (MOF) tanks can safely stash up to 1,000 kg of hydrogen at only ~30 bar. That’s way lighter and denser than traditional high-pressure cylinders.

Technical Blueprint

• Green hydrogen production: A 4.0 MW electrolyser splits water into hydrogen and oxygen using port-based renewables.
• Advanced hydrogen storage: Iron salt–based MOF tanks adsorb hydrogen at low pressure, cutting risks and saving quayside real estate.
• Dual-fuel engines: Tugs start with a hydrogen–diesel blend, then smoothly transition to pure hydrogen as supply chains and bunkering networks mature.

On the money side, the financial model contrasts upfront capex—electrolyser plus storage hardware—against ongoing savings from cheaper energy and maintenance. Sure, you’re looking at low tens of millions of pounds up front, but over 15 years you’d slice 20–30% off fuel and servicing bills. Factor in rising carbon prices, and hydrogen’s edge only sharpens.

MOF vs Conventional Storage

You’ve heard of 350–700 bar cylinders or cryo-tanks—both bulky and energy-hungry. Rux’s MOF tanks operate around 30 bar, trimming compressor loads and lowering risk. Their compact footprint frees up prime dock space, a big win in a busy naval port.

Engine Technology Pathways

Tug operators can ease in with a 20% hydrogen-diesel retrofit or leap straight into dedicated hydrogen engines that eliminate carbon emissions entirely. The dual-fuel route keeps initial engine costs down and taps existing maintenance know-how, while full-hydrogen power delivers the ultimate environmental payoff once hydrogen infrastructure is in place.

Strategic Implications for Maritime Decarbonization

Associated British Ports has pledged to decarbonize its UK ports by 2040, and sees hydrogen production and offtake partnerships as critical. Meanwhile, Boluda Towage—currently a diesel-fleet operator in Portsmouth—already uses shore power to slash emissions while idling, proving cleaner tech can get a head start even before the fuel swap.

Regulatory Roadmap

The rulebook needs an overhaul. The UK Maritime and Coastguard Agency is updating guidelines for hydrogen fuel systems, and ABP is designing standard shore-side loading protocols. It’s all about integrating hydrogen infrastructure into existing safety and supply chains.

Funding Models

Grants only go so far. Public–private partnerships could shoulder the early capex, with ports locking in long-term hydrogen supply deals and suppliers like Rux offering leasing plans for their MOF tanks—spreading costs over several years and lightening the upfront load.

Portsmouth’s Evolution

As a historic naval hub and home to the Royal Navy, Portsmouth is the perfect testbed for maritime innovation. Already a leader in shore-power for tugs and ferries, the port’s shift toward hydrogen mirrors broader industrial decarbonization trends kicked off by the UK’s 2020 net-zero targets.

Maritime Emissions Context

The International Maritime Organization pegs shipping at roughly 3% of global CO₂ emissions, with ports adding local NOₓ and particulate pollutants. Diesel tugs, with their high power-to-weight demands, are hotspots. Swapping in hydrogen tackles both climate goals and air-quality standards under the UK’s Environment Act 2021.

Port Community Impact

Portsmouth’s ~215,000 residents stand to breathe easier as NOₓ and particulates fall. Local crews and service providers can upskill through training programs from Serco and ABP, ensuring the workforce is ready for hydrogen operations.

Export and Replication Potential

If Portsmouth nails this, it becomes a blueprint for other UK—and even global—ports aiming at industrial decarbonization. By bundling electrolysis, hydrogen production, hydrogen storage and engine retrofits into one turn-key solution, technology providers like Rux could spearhead a low-carbon marine export market.

Interim Solutions

While full hydrogen bunkering might still be a few years off, shore power is a stellar bridge. Serco and Boluda already mandate onshore plugging for idle tugs, cutting greenhouse gas and NOₓ emissions by up to 85% versus diesel generators.

Timeline to Deployment

Here’s the rollout: finish detailed engineering and safety approvals by mid-2026, build the electrolyser and MOF tanks in 2027, kick off dual-fuel trials in late 2026, and aim for full hydrogen operations by 2029. This phased approach lines up neatly with ABP’s 2040 decarbonization goal and the UK’s Clean Maritime Plan for net-zero shipping.

Ultimately, this feasibility study isn’t just about one port. It marks a turning point in maritime industrial decarbonization, where harbor operators, energy producers and regulators all row in the same direction. The next two years—packed with policy decisions and investment deals—will tell if this pilot turns into a full-scale revolution for UK ports and beyond.