offshore renewable energy
The Intergovernmental Panel on Climate Change’s 2023 Synthesis Report confirms that progress towards mass decarbonisation is happening slower than previously hoped, and highlights the need for “deep, rapid and sustained” emission reductions this decade. 
This urgency was reflected in the UK Government’s recent proposal to the International Maritime Organization which called for 37% and 96% cuts in international shipping emissions by 2030 and 2040 respectively. It is also evident in their ambitious targets for offshore renewable energy (ORE), upscaled in response to the Net Zero strategy and energy security concerns. These are now set to increase deployment of offshore wind from 14GW to 50GW, including the delivery of 5GW of floating offshore wind, by 2030. This significant expansion aligns with the ambition to fully decarbonise the UK’s electricity production by 2035.
Both nationally and globally, the maritime sector is late to decarbonisation. It currently faces many uncertainties in terms of policy and technology which, compounded with cost and competition pressures, creates significant barriers to the sector achieving rapid progress. Changes in landside operations, technology and behaviours are essential components of the maritime system and can have as much impact in overall carbon footprint as new technologies in the fleet. The shift from fossil to renewable energy sources in the maritime sector and the wider UK electrification and hydrogen strategy for decarbonisation, requires a systems approach.
There is a natural alignment between ORE and the decarbonisation of the maritime sector. ORE is a reliable source for renewable electricity and green hydrogen, both of which are key components in future propulsion systems for clean maritime. Low carbon alternative fuels – hydrogen, ammonia and methanol, nuclear propulsion and electrification – are being investigated and may provide options for transitioning away from fossil fuel-reliant propulsion, providing a menu of solutions for the different sub-sectors within maritime shipping.
ORE farms, located at sea and nearshore in the marine environment, could provide an opportunity for the offshore recharging and re-fuelling of vessels, to reduce the carbon footprint in marine transport operations and the pressure on ports. The costs and carbon impact of energy transport could also be reduced further by co-locating the sources of energy to power shipping with the demand for recharging and re-fuelling stations. Offshore charging points could be provided for electric vessels, and where electrolysers for hydrogen production are integrated within ORE farms, hydrogen re-fuelling stations would be available.
The integration of green hydrogen production with ORE is being explored as a means to provide electricity for electrolysis responding to the target of a 5GW green hydrogen production capacity by 2030. Hydrogen is also seen as a potential solution for energy storage and dispatch within the electricity grid, and may have a role as an alternative fuel in the maritime sector. It can be used to produce ammonia and methanol, both identified as significant in the transition away from fossil fuels, with the advantage of being suitable for use in some existing propulsion systems.
With vessels often being in service for over 30 years, ORE may also open up other Power-to-X solutions as a stop-gap. Large-scale seaweed aquaculture is being planned here in the South West, and also internationally, to sequester carbon, but possibly as a feedstock for a range of synthetic biofuels that power from ORE can produce in volume for existing fleet operations.
ORE must grow significantly faster than previously projected to meet the new and accelerated UK government targets. That growth requires large-scale deployment of novel floating offshore wind (FOW) technology underpinned by research-led innovation and record upscaling and upskilling of the UK workforce and supply chain. The recent Scotwind leasing process may see as much as 27.6GW of new generating capacity built over the next decade. Closer to home for us, the Celtic Sea programme is intended to provide 4GW of renewable energy capacity by 2035, with an expected additional 20GW by 2045.
Developing innovative floating offshore wind technology in deeper water will require new supply chains to carry out installation and servicing throughout the lifetime of the ORE farms. The design and development of new fleets, and vessels specifically built for the installation of ORE technologies, will be essential. As will fleets for data collection during planning and consenting stages, for ongoing monitoring of environmental data, and for through-life monitoring and inspection of structures, moorings and cables. Operations and maintenance, either on station or towing to port, will also be fundamental to assess integrity and carry out repairs.
A further opportunity to unlock maritime decarbonisation is through the rapid uptake of autonomous systems for ORE marine operations. Self-sufficient platforms for data collection, inspection, monitoring and repair, can be achieved using fully autonomous combinations of surface, airborne and sub-surface innovative fleet deployed from a single base vehicle or mother ship. Such systems could be based offshore and recharge on site.
All of these vessels could be fully decarbonised from the outset, without the need to transition existing propulsion systems. It presents a real opportunity for ORE to not only aid the global drive for net zero, but to serve as a trailblazer for clean maritime and kickstart progress in green shipping. Through a systems-thinking approach, we can tackle complex and ever more urgent global challenges in climate change mitigation. However, that can only realistically be achieved through trans-disciplinary collaborations and a holistic approach that brings together technical, economic, and environmental aspects to deliver practical solutions.

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Fuel powering shipping and wider port activity has been some of the most polluting fuel used across all transport modes. Globally, the maritime sector needs to do more to reduce greenhouse gas emissions and air pollutants as these affect the environment profoundly accelerating climate change.
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