Assessment 1: Shipping Decarbonisation — Evaluating the IMO 2050 Strategy and the Transition to Alternative Marine Fuels
1. Module Context and Rationale
Write a 2,500–3,000-word research essay that critically evaluates the feasibility of the IMO’s 2050 decarbonisation strategy, with comparative analysis of alternative marine fuels and a critical assessment of the regulatory instruments introduced to govern the transition. This assessment forms the first major piece of individual written work in the module and is designed to build your capacity to synthesise technical, economic, and regulatory dimensions of the shipping sector’s most pressing long-term challenge.
International shipping contributes approximately 3% of global greenhouse gas (GHG) emissions, and with maritime trade volumes projected to triple by 2050, those emissions will rise sharply unless the sector acts. In July 2023, at MEPC 80, the IMO’s Member States agreed a revised GHG strategy that replaced the earlier 2018 50%-reduction target with a more ambitious commitment to net-zero emissions “by or around, i.e. close to, 2050,” supported by checkpoints requiring at least 20% reduction (striving for 30%) by 2030 and 70% reduction (striving for 80%) by 2040. In April 2025, the IMO’s MEPC 83 session released a draft of the IMO Net-Zero Framework — a set of proposed amendments to MARPOL Annex VI — that, if formally adopted, will introduce binding GHG reduction requirements from 2028 and a mandatory GHG pricing mechanism, making it the most significant regulatory development in maritime environmental law in a generation.
Yet expert opinion on whether these targets are achievable remains sharply divided. As of June 2024, 98% of ships at sea still depended on conventional fossil fuels. No single zero-emission alternative has reached commercial scale, and the capital expenditure, bunkering infrastructure, and production capacity needed to transition even a fraction of the global fleet to green ammonia, e-methanol, or green hydrogen by 2030 remain, on current trajectories, well below what the checkpoints require. This assessment asks you to situate yourself in that debate — not as a bystander, but as someone who can evaluate the technical and regulatory evidence and reach a reasoned, specific conclusion.
2. Assessment Task
Write a 2,500–3,000-word research essay in response to the following question:
The essay must be analytical throughout. Describing what the IMO strategy says, or listing the properties of different fuels, is insufficient. A strong submission will evaluate whether the measures being adopted are proportionate to the scale of the challenge, will identify where the gaps are between regulatory intent and operational reality, and will use specific technical and economic evidence to support its argument.
3. Learning Outcomes Assessed
- Critically evaluate the IMO’s decarbonisation regulatory framework, including the 2023 revised GHG Strategy, MARPOL Annex VI instruments, and the proposed Net-Zero Framework, in terms of their scope, enforceability, and adequacy.
- Compare the technical characteristics, emission reduction potential, safety profile, and infrastructure requirements of at least two alternative marine fuels, drawing on current engineering and scientific literature.
- Analyse the economic and geopolitical dimensions of the maritime energy transition, including bunkering infrastructure gaps, the role of green shipping corridors, and equity concerns for developing-nation flag states.
- Construct a coherent, evidence-based argument about the feasibility of the IMO’s 2050 target, identifying specific regulatory or technological reforms needed to bridge the gap between current trajectories and stated goals.
- Produce a well-structured, accurately referenced research essay appropriate to postgraduate or final-year undergraduate level in marine engineering or maritime studies.
4. Task Requirements and Structural Guidance
The essay should be written in continuous prose, not as a report with section headings. The following elements must appear and must be integrated into a coherent analytical argument.
4.1 Introduction (approximately 250–300 words)
Establish why shipping decarbonisation matters at this particular moment in regulatory history. Introduce the revised 2023 IMO Strategy and the IMO Net-Zero Framework as the primary instruments under analysis. State your thesis clearly — that is, your evaluative position on whether current measures are feasible and adequate. Do not fill the introduction with background detail that belongs in the main analysis.
4.2 The Regulatory Architecture: From EEDI to the Net-Zero Framework
Your analysis of the regulatory framework must address the following:
- The trajectory of IMO environmental regulation from the Energy Efficiency Design Index (EEDI, mandatory for newbuilds since 2013) through the Energy Efficiency Existing Ship Index (EEXI, in force from January 2023) and the Carbon Intensity Indicator (CII, with annual rating requirements from 2023 and progressively tightening thresholds from 2026 onwards).
- A critical evaluation of what EEXI and CII can and cannot achieve: both instruments operate on carbon intensity (grams of CO₂ per tonne-mile) rather than absolute emission reductions, which means total fleet emissions can rise even as individual vessel ratings improve, if trade volumes grow. Evaluate this structural limitation explicitly.
- The IMO Net-Zero Framework, finalised in draft form at MEPC 83 in April 2025, which proposes mandatory GHG Fuel Intensity (GFI) limits from 2028 and a two-tier GHG levy mechanism. Assess whether the draft framework, if adopted in October 2025 as scheduled, provides the regulatory certainty that shipowners, fuel producers, and port authorities need to commit to long-term investment in alternative fuels.
- The EU’s parallel regulatory moves — the FuelEU Maritime regulation (in force from January 2025), which mandates GHG intensity reductions for vessels calling at EU ports, and the inclusion of international shipping in the EU Emissions Trading System (ETS) from 2024 — and what these regional instruments reveal about the adequacy of the global IMO framework.
4.3 Alternative Fuels: Comparative Technical and Economic Analysis
Select at least two fuels from the following four and provide a comparative analysis. Your comparison must be grounded in specific technical data and current literature, not general descriptions.
- LNG (liquefied natural gas): Currently the most commercially deployed alternative fuel, with over 800 LNG-capable vessels in the global fleet as of 2024. LNG offers a reduction of approximately 25% in CO₂ compared to heavy fuel oil on a tank-to-wake basis, but methane slip from dual-fuel LNG engines significantly undermines its well-to-wake GHG performance. The most widely used LNG cruise engines have been found to offer no net climate benefit when methane leakage is accounted for over a 20-year horizon. Assess its role as a transition fuel rather than a long-term zero-emission solution.
- Ammonia (NH₃): Produces zero CO₂ in combustion and is increasingly regarded as the most scalable long-term alternative fuel for large-ship deep-sea trades, with e-ammonia projected to reach 35% of the global marine fuel mix by 2050 under baseline scenarios. However, ammonia is acutely toxic, presents NOₓ emissions challenges, and requires ammonia cracking technology and infrastructure investment that does not yet exist at scale in most bunkering hubs globally. The UK Maritime and Coastguard Agency issued guidelines for ammonia as a marine fuel in April 2025, marking a regulatory step forward, but safety standards remain provisional.
- Green methanol: Maersk’s orders for 19 dual-fuel methanol vessels and its bunkering agreement with the Port of Shanghai represent the most prominent commercial-scale commitment to methanol in shipping. Methanol reduces SOₓ by over 95% and NOₓ by up to 80% compared to conventional fuel. However, methanol has approximately half the energy density of conventional marine fuel by volume, requiring larger or more frequent bunkering, and current methanol production is predominantly fossil-based. Green methanol from renewable sources remains expensive and supply-constrained, with methanol projected to account for only approximately 13% of the marine fuel mix by 2050.
- Green hydrogen: The cleanest fuel in combustion terms, but hydrogen’s extremely low volumetric energy density, cryogenic storage requirements at -253°C, and the near-absence of bunkering infrastructure at any commercial port make it viable primarily for short-sea ferry operations and inland waterways rather than deep-sea trades. Discuss its realistic role in the transition timeline.
4.4 Feasibility Assessment: Where the Gaps Are
- Evaluate the mismatch between regulatory ambition and current fuel availability. As of mid-2024, zero-emission fuels are estimated to account for well under 1% of the global marine fuel supply, and the 2030 checkpoint requires at least 5%, striving for 10%, of international shipping’s energy to come from zero or near-zero GHG fuels. Assess whether this gap is closable on the current investment trajectory.
- Address the infrastructure deficit at ports that are strategically significant for the main trade corridors under study in this module: Rotterdam and Hamburg in Europe, Singapore, Jebel Ali (UAE), Port Said (Egypt), and the bunkering hubs of the Arabian Sea and GCC region. Note that while Rotterdam has active e-ammonia pilot projects and Shanghai has committed to green methanol bunkering with Maersk, many secondary and developing-nation ports have no roadmap for alternative fuel provision.
- Discuss the equity dimension: the IMO Net-Zero Framework’s proposed levy mechanism could generate revenues for a Just and Equitable Transition fund, but the design of that fund — its allocation criteria, governance, and disbursement mechanisms — remains unresolved. Developing-nation flag states and those whose export economics depend heavily on shipping face disproportionate transition costs.
- Engage with the expert elicitation evidence from Laskar et al. (2025), which found that international shipping appears on track to meet its 2030 carbon intensity targets but is likely to miss the 2050 net-zero goal under current policy trajectories, absent more aggressive mid-term intervention.
4.5 Recommendations
Develop a minimum of three specific, targeted, and evidence-grounded recommendations. Each recommendation must identify: who is responsible for implementation (IMO, flag state, port authority, shipowner, or cargo-owner coalition); what specific instrument, mechanism, or investment would carry the change; and what measurable outcome would constitute success. Generic recommendations for “more investment” or “stronger cooperation” without this level of specificity will not meet the assessment criteria.
4.6 Conclusion (approximately 250–300 words)
Return directly to the essay question. Synthesise your key findings. State your evaluative position clearly — whether you conclude the 2050 target is feasible under current measures, feasible with specific reforms, or at significant risk of being missed — and explain the most consequential gap in the current framework.
5. Specific Requirements
- The essay must be written in continuous academic prose. Section headings or bullet points within the essay body are not permitted; these belong only in any appendix you include, which does not count toward the word limit.
- A minimum of ten (10) credible sources must be cited. At least six (6) must be peer-reviewed journal articles or book chapters published between 2019 and 2025. IMO regulatory documents (MEPC resolutions, MARPOL amendments), EU regulations (FuelEU Maritime), and classification society guidelines count as primary sources but do not replace the peer-reviewed minimum.
- All technical data must be attributed to a named source — DNV, Lloyd’s Register Maritime Decarbonisation Hub, Oxford Institute for Energy Studies (OIES), BIMCO, UNCTAD, or equivalent institutional authority. Unattributed statistics or emissions figures will be penalised.
- The comparative fuel analysis must cover at least two distinct fuel types in meaningful technical depth. A superficial paragraph on each fuel does not satisfy this requirement — the comparison must engage with well-to-wake emissions, infrastructure availability, cost trajectory, and safety regulation.
- Students based in UAE, GCC, or Middle Eastern institutions are encouraged to include specific reference to green shipping corridor development in the Arabian Gulf and Red Sea regions, noting the role of ports such as Jebel Ali, King Abdullah Port (Saudi Arabia), and Salalah (Oman) in bunkering transition planning.
- The word count must be stated on the title page. Submissions outside the 2,500–3,000-word band by more than 10% incur a penalty under university regulations.
- The title page must include your student ID number (not your name), module code, module title, essay title or working title, word count, and submission date.
6. Marking Criteria and Rubric
| Criterion | Weight | High Distinction / Distinction (75%+) | Credit / Merit (60–74%) | Pass (50–59%) | Fail (<50%) |
|---|---|---|---|---|---|
| Critical Argument and Analytical Depth Clarity and coherence of thesis; evaluative vs descriptive balance; sustained original analysis |
30% | A clear, defensible thesis is maintained throughout; the essay consistently evaluates rather than describes; tensions between regulatory ambition and operational reality are identified with precision; counterarguments are engaged. | Clear thesis with solid analysis; some sections slip into description, particularly in the fuel comparison; generally evaluative but loses focus at points. | Argument present but underdeveloped; essay is predominantly descriptive, particularly in the regulatory section; limited critical engagement with feasibility. | No identifiable thesis; essay is a descriptive summary of the IMO strategy and fuel properties without evaluation; question not addressed. |
| Technical and Regulatory Knowledge Accuracy of fuel data; command of EEDI, EEXI, CII, Net-Zero Framework; understanding of bunkering economics |
25% | Accurate, detailed command of regulatory instruments and fuel characteristics; well-to-wake versus tank-to-wake distinction correctly applied; methane slip, GFI limits, and levy mechanism addressed correctly; evidence of reading beyond module core texts. | Sound understanding of the main regulatory and technical issues; minor gaps or occasional inaccuracy in technical detail, for example around CII thresholds or methane slip. | Basic understanding; limited engagement with the technical specifications of the fuels analysed; key instruments such as the Net-Zero Framework absent or mischaracterised. | Significant technical errors; conflation of tank-to-wake and well-to-wake emissions; key regulatory instruments absent or fundamentally misunderstood. |
| Use of Evidence and Sources Source quality, range, currency, and integration; attribution of technical data |
20% | Excellent range of credible and current sources; technical data attributed to named institutional sources; sources integrated analytically rather than as filler; minimum requirements comfortably exceeded; majority of sources from 2022–2025. | Good range of relevant sources; mostly well-integrated; minor attribution gaps in technical data. | Adequate source count but limited range; some unattributed technical claims; over-reliance on IMO.org or non-peer-reviewed web content without critical triangulation. | Insufficient sources; minimum requirements not met; heavy reliance on websites without attribution; peer-reviewed minimum not achieved. |
| Comparative Fuel Analysis Technical depth and specificity of the fuel comparison; engagement with infrastructure and safety dimensions |
15% | At least two fuels analysed with specific technical data on emissions reduction potential, infrastructure readiness, cost trajectory, and safety regulation; comparison is evaluative and identifies trade-offs rather than describing each fuel in isolation. | Two fuels compared adequately; some sections are descriptive rather than comparative; infrastructure and safety dimensions partially addressed. | Fuels described separately without meaningful comparison; no engagement with infrastructure, cost, or safety dimensions beyond surface level. | Fuel comparison absent or too superficial to satisfy the requirement; one fuel mentioned briefly without any technical engagement. |
| Structure, Academic Prose, and Referencing Essay organisation; paragraph logic; Harvard/APA 7th accuracy |
10% | Logically structured throughout; paragraphs have clear functions and transitions are purposeful; academic register consistent; referencing correct and complete including for IMO instruments and EU regulations. | Generally well-organised with minor structural weaknesses; referencing mostly correct; academic register maintained. | Adequate organisation; noticeable referencing errors; some lapses in academic register or sentence-level clarity. | Poorly structured; frequent referencing omissions or errors; non-academic register; technical terms used incorrectly. |
7. Submission Instructions
- Submit via Turnitin through the module Blackboard / Canvas / Moodle page. Accepted formats: Microsoft Word (.docx) or PDF.
- Anonymous marking is in place. Use your student ID number only on the title page and in the document footer if applicable — not your name.
- Late submissions without a pre-approved extension are subject to the university’s late penalty (typically 5 marks per 24-hour period or equivalent reduction, up to a maximum of 10 working days, after which a mark of zero is recorded).
- Extensions must be applied for through the university’s mitigating circumstances or extension portal before the deadline. Do not contact the module leader directly to request an extension.
8. Guidance Notes for Students
On staking and sustaining an argument
Many students write essays that describe the IMO strategy accurately and then list the pros and cons of each fuel without ever reaching a conclusion. The marking criteria reward essays that take a specific, defensible position — for example, that the 2050 target is technically achievable but the current regulatory instruments are not creating the investment signals needed to get there on schedule, and that without a well-designed GHG levy mechanism with targeted rewards for e-fuels, the 2030 checkpoint will be missed. Alternatively, you might argue the opposite: that incremental improvements in EEXI compliance, combined with the scaling of green methanol and the EU ETS for shipping, provide a credible pathway. Either position can earn a distinction; a description of both sides without resolution cannot.
On well-to-wake versus tank-to-wake emissions
The IMO’s Net-Zero Framework, unlike earlier EEDI and EEXI instruments, uses well-to-wake (full lifecycle) GHG accounting for its GFI limits rather than tank-to-wake (combustion-only) CO₂. This is a significant regulatory shift. It means that LNG, which appears clean on a tank-to-wake basis because it produces approximately 25% less CO₂ than HFO in combustion, scores poorly on a well-to-wake basis once methane slip from dual-fuel engines and upstream production emissions are included. Your fuel analysis must reflect this distinction; essays that conflate the two accounting methods will lose marks in the Technical and Regulatory Knowledge criterion.
On using the IMO Net-Zero Framework
The framework was finalised in draft at MEPC 83 in April 2025 and was scheduled for adoption at MEPC 83.1 in October 2025. At the time of this brief being issued, the formal adoption decision may or may not have been completed — check the IMO website (imo.org) directly for the current status and cite accordingly. Do not assume adoption; describe the draft text and the scheduled timeline accurately.
Key module resources and primary sources
- IMO Net-Zero Framework — current status and draft text: imo.org/en/mediacentre/hottopics/pages/cutting-ghg-emissions.aspx
- IMO 2023 Revised GHG Strategy (MEPC 80, Resolution MEPC.377(80)) — imo.org
- MARPOL Annex VI — EEXI and CII Regulations: imo.org
- FuelEU Maritime Regulation — EUR-Lex: eur-lex.europa.eu
- Lloyd’s Register Maritime Decarbonisation Hub — Future of Maritime Fuels Report: thedecarbhub.org
- Oxford Institute for Energy Studies (OIES) — Practical considerations for e-ammonia adoption (ET49, 2025): oxfordenergy.org
- Global Maritime Forum — IMO Policy Measures and Decarbonisation Insights: globalmaritimeforum.org
Example Student Response
The IMO’s revised 2023 GHG strategy marks a step change from earlier maritime environmental commitments, replacing the ambiguous 50%-reduction target from 2018 with a net-zero pathway supported by legally anchored interim checkpoints and, in draft form at least, a binding fuel intensity standard and levy mechanism under the proposed Net-Zero Framework. Whether those instruments are proportionate to the pace of change required is a different matter. Laskar et al. (2025), drawing on systematic expert elicitation across the maritime sector, conclude that shipping appears on track to meet its 2030 carbon intensity targets but is likely to miss the 2050 net-zero goal under current trajectories, absent a more aggressive mid-term regulatory push. The EEXI and CII instruments, which have been in force since January 2023, are carbon intensity measures — they track how efficiently individual vessels move cargo — not absolute emission caps, which creates a structural problem: if trade volumes grow as projected, the fleet’s total GHG output may rise even as the average vessel’s CII rating improves. LNG, the one alternative fuel that has reached commercial deployment at scale, with over 800 capable vessels as of 2024, compounds the problem: on a well-to-wake basis accounting for methane slip from dual-fuel engines, the most widely used LNG propulsion systems can produce lifecycle GHG emissions comparable to or even higher than heavy fuel oil, undermining their role as a genuine transition fuel. Green ammonia and e-methanol offer far stronger decarbonisation potential but face a production and bunkering infrastructure deficit that, on current investment trajectories, makes the 5–10% zero-emission fuel share target for 2030 extremely difficult to achieve. The gap between regulatory ambition and operational reality may be closable with a well-designed GHG levy that generates revenues for e-fuel incentives and a Just and Equitable Transition fund — but the design of that mechanism, at the time of writing, remains contested among IMO Member States.
What makes this assessment period particularly consequential is the convergence of several regulatory timelines. The EU ETS for shipping entered force in 2024, FuelEU Maritime began in January 2025, and the IMO’s draft Net-Zero Framework is scheduled for formal adoption in late 2025, with binding GFI limits applying from 2028. Studies evaluating the GHG fuel intensity of oil tankers, container ships, and bulk carriers under the Net-Zero Framework’s proposed limits have found that conventional fuels are unable to meet future GFI thresholds, producing significant compliance deficits and balancing costs when measured against the framework’s direct and base compliance targets from 2028 onwards. The Lloyd’s Register Maritime Decarbonisation Hub projects that e-ammonia could reach 35% of the global marine fuel mix by 2050, but notes that supply is unlikely to meet demand without early regulatory intervention — the same report suggests biofuels, projected to supply roughly 34% of demand by 2050, will face a supply shortage of around 4 EJ against a demand of approximately 4.6 EJ. Port decarbonisation investment is the least discussed but arguably most consequential bottleneck: without ammonia and methanol bunkering capacity at GCC hubs like Jebel Ali, at Red Sea corridor ports such as Port Said and Salalah, and at major Asian transshipment centres, shipowners have no credible path to compliance regardless of the regulatory timeline they face.
9. References / Learning Materials (Harvard Format)
- Laskar, R., Fletcher, S.E.M., Lohrmann, A., Psaraftis, H., Rehmatulla, N. and Bouman, E.A. (2025) ‘Expert assessments of maritime shipping decarbonization pathways by 2030 and 2050’, Earth’s Future, 13(4), e2024EF005255. Available at: https://doi.org/10.1029/2024EF005255
- Babalola, O., Rong, G. and Okeke, C.U. (2025) ‘Shipping sector decarbonisation measures: a review’, Cleaner Energy Systems, article in press. Available at: https://doi.org/10.1016/j.cles.2025.100173 [ScienceDirect]
- Bayraktar, M. and Nuran, M. (2025) ‘Evaluating the greenhouse gas fuel intensity of marine fuels under the maritime net-zero framework’, Sustainability, 18(1), p. 184. Available at: https://doi.org/10.3390/su18010184
- Sarantopoulos, F. (2024) Decarbonizing the shipping industry through innovative fuel technologies. Master’s thesis, MIT Sloan School of Management. Available at: https://dspace.mit.edu/bitstream/handle/1721.1/156005/sarantopoulos-fotis072-msms-sloan-2024-thesis.pdf
- Notteboom, T., Pallis, A. and Rodrigue, J-P. (2022) Port Economics, Management and Policy. New York: Routledge. Available at: https://doi.org/10.4324/9780429318184
- Oxford Institute for Energy Studies (2025) Fueling the Future: Practical Considerations for E-ammonia Adoption in the Shipping Sector. Oxford: OIES Energy Transition Paper ET49. Available at: https://www.oxfordenergy.org/wpcms/wp-content/uploads/2025/08/ET49-Practical-considerations-for-e-ammonia-adoption.pdf