After a year of devastating climate disasters, nations at COP 28 in Dubai in December signalled the need for the “end of the fossil fuel era”. To meet that ambition, 2024 will need to see a major acceleration in global action to address climate change. Here, Simon Bullock, Alice Larkin, and James Mason from the Tyndall Centre at The University of Manchester outline new research setting out what the shipping sector needs to do to play its part in meeting the climate goals set out in the Paris Climate Agreement, in the UK and globally.

• The international shipping sector, made up of thousands of massive cargo ships propelled by burning fossil fuels, emits carbon dioxide (CO₂) roughly equivalent to the entire country of Germany.
• Immediate action is needed to reduce shipping emissions, to put it on course with the Paris Agreement’s goal of limiting global heating to 1.5°C.
• New research published by Tyndall researchers at The University of Manchester assesses whether The International Maritime Organisation’s updated climate targets are strong enough, and implications for the UK.

Meeting the Paris Agreement target to limit global heating to 1.5°C means deep cuts to fossil fuel use this decade, in every sector of the global economy. One of these sectors is shipping. In summer 2023 The International Maritime Organisation (IMO) set out a new strategy, and new targets, for international shipping to cut its greenhouse gas emissions.

The new IMO strategy sets “indicative checkpoint” and “strive” targets for 2030 and 2040, on a pathway to zero emissions by around 2050. Our latest research concludes that the checkpoint targets are not sufficient, but, under generous assumptions, the “strive” targets of 30% reductions by 2030 and 80% by 2040 are compatible with the 1.5°C limit. These strive targets should be considered a minimum level of ambition for the sector.

There is also an urgency to implementing these targets: any further delay in cutting emissions would push compatibility with 1.5°C out of reach.  Therefore, it is emissions cuts this decade that must be prioritised. It is imperative that policy makers and the industry focus on accelerating deployment of known technologies and practices to meet the “strive” goal of 30% by 2030.

Because IMO processes are slow, it is likely that it will be 2027 before new global policies are agreed to support delivery of these targets. Consequently, it is critical that front-runner nations and industry step-up and drive decarbonisation.

Clean maritime plan

The UK aspires to be one of these front-runners. Its 2019 Clean Maritime Plan (CMP) stated the clear aim to be “seen globally as a role model in this field, moving faster than other countries and faster than international standards”. This 2019 plan was strong on rhetorical ambition, but was comparatively light on supporting policy and targets, which were flagged as requiring development.

The Government has suggested for some time that the CMP would be refreshed by the end of 2023, with the latest official update now stating that a new version will be published “as soon as possible”. This CMP refresh is vital for the UK to drive down its shipping emissions. The CMP refresh should signal that the Government will develop a strategy within the year for reducing its shipping emissions in line with the Paris Agreement, and we contend that the success of the strategy should be based on the following five criteria:

Ambition

The IMO has set a strive target for international shipping emissions of 30% cuts in greenhouse gases by 2030. The United Nations Framework Convention on Climate Change principles of responsibility and capability require the UK to set stronger targets than the global average, implying at least 50% reductions on 2008 levels by 2030 for its domestic shipping emissions, on a pathway to zero emissions by 2040.

Scope

It is almost certain that the CMP refresh will focus on the UK’s domestic maritime emissions. However, the UK has legislated that its share of international shipping emissions will become part of the UK’s carbon budgets from 2033. These emissions will then need to fall extremely rapidly. It’s imperative that the UK acts now to start cutting these emissions, and not wait until 2033. The precedent is already there – the UK has led initiatives on international green corridors – so there is no reason why the UK cannot develop a strategy for its international shipping emissions, to complement work at the IMO. The CMP refresh should signal that the Government will develop a strategy within the year for reducing its international shipping emissions in line with the Paris Agreement.

Economic instruments

The UK’s CMP and Zero Emission Vessels and Infrastructure competitions have been welcome initiatives to accelerate deployment of clean maritime technologies. However, unfair market distortion, where highly polluting fuels face very low levels of tax while cleaner energy sources such as electricity face very high levels of tax, means that greener alternatives will always struggle to be deployed. The recent inclusion of domestic maritime emissions in the UK emissions trading scheme (ETS) is welcome, but this only covers very large vessels. The ETS should be extended to vessels over 400 tonnes and should also cover the UK’s share of international shipping emissions.

Shore power

Shore power can help cut maritime pollution by allowing ships to plug-in while at berth. This is also an essential technology for battery recharge of hybrid and all-electric vessels. Despite the benefits, global deployment of shore power is slow, particularly in the UK. The Government should introduce an integrated package of support measures to complement the use of a carbon price on marine fuel oils. This could comprise three measures. Firstly, a reduction in taxes on shore power electricity to enable shore power projects to compete more fairly with less taxed marine fuel oils; this type of exemption already exists in the UK for other industries. Secondly, capital funding infrastructure support for ports, and thirdly, setting a clear Zero Emission Berth standard for vessels visiting UK ports.

Wind propulsion

Much focus in shipping is on new fuels, such as ammonia, bio-methanol, and hydrogen. Low carbon sources of propulsion are essential, but new ‘green’ liquid fuels need major bunkering infrastructure, have high costs, and will take many years to be deployed at scale. By contrast, harnessing wind power through wind-assist propulsion systems requires no bunkering, is free and can be deployed now. Investment in these technologies in the short term will also help to shield ship owners from future uncertainties around fuel prices and bunkering availability. New Tyndall research highlights that employing wind propulsion systems integrated with route optimisation can cut emissions by around 20% on average. Retrofitting wind propulsion should be a priority for all shipping segments, with some routes linked with the UK particularly suitable for this technology, such as those in the North Atlantic and North Sea. The CMP should explicitly prioritise funding and policy support for investment in wind propulsion technology systems, irrespective of future fuel developments, given the likely price hike anticipated for any new truly ‘green’ fuel.

Tackling climate change is desperately urgent. The new IMO targets set a clear direction – that the shipping sector must cut its emissions deeply and rapidly. The UK aspires to be a global leader in Clean Maritime – if its new CMP refresh can set clear targets for 2030, expand its coverage to include international emissions, put in place strong economic instruments, and support wind and shore power technologies, then the UK’s revamped maritime strategy would truly have wind in its sails.