SAF Was Already Short. Then Hormuz Closed.
What the current data shows, and some unexpected ripple effects.
In our online seminar of 21 January 2026, Decarbonising Flight: Strategic Policy, Industrialization, and Early Adoption on the Path to Zero-Emission Aviation, we framed the current technology landscape as a two-horizon problem. Sustainable Aviation Fuel (SAF) was identified as the dominant near-term lever, and hydrogen-based pathways (direct combustion, fuel cells, Power-to-Liquid) as the longer-term destination. Four months on, the near-term horizon is being tested in a way the seminar could only anticipate. The regional conflict in the Persian Gulf that began at the end of February 2026 and the effective closure of the Strait of Hormuz from early March have layered a conventional jet-fuel supply shock on top of a SAF market that was already operating well below its mandate trajectory. Because SAF is closely coupled to the conventional fuel system, through blending, pricing, hydrogen inputs and feedstock logistics, the two situations interact in ways that are not always obvious. This article maps those linkages, and closes on what is visible in Bremen.
The supply baseline
SAF is the umbrella term for jet fuels made from non-petroleum sources, such as used cooking oil, animal fats, agricultural residues, municipal waste, or in the most ambitious pathways, low-carbon hydrogen combined with captured carbon dioxide. The chemistry is engineered to be close enough to conventional kerosene that the resulting fuel can be loaded into the same aircraft tanks, pumped through the same airport hydrant systems and burned in the same engines without modification. That property, “drop-in”, is the entire commercial premise of SAF. It is also the source of every supply linkage discussed below.
A few facts establish the baseline. SAF is certified under the international standard ASTM D7566, which defines the specification a synthesised aviation fuel must meet and lists the production routes approved for use. Eleven such routes are approved; in practice one dominates. The Hydroprocessed Esters and Fatty Acids, Synthetic Paraffinic Kerosene route (HEFA-SPK) takes waste oils and fats, removes their oxygen content using hydrogen at high temperature and pressure, and produces hydrocarbons in the kerosene range. It accounts for roughly 87% of global SAF capacity in 2026. Importantly, no certified pathway today permits more than 50% SAF in the final blend; the remainder is conventional Jet A-1, the standard kerosene used in commercial aviation.
The volumes are small relative to what policy now requires:
- Global SAF reached approximately 0.53% of jet fuel use in 2024 and around 0.6% in 2025.
- IATA (the International Air Transport Association) projects 2.4 million tonnes (Mt) for 2026, around 0.8% of total jet fuel consumption.
- In Europe, EASA (the European Union Aviation Safety Agency) reports that SAF facilities currently in operation would deliver just over 1 Mt by 2030 under its “Operating” scenario, and that production capacity currently under construction could supply the approximately 2.8 to 3.2 Mt that ReFuelEU is expected to require in 2030, provided the announced projects ramp up on time. This 2030 requirement is based on EASA’s forecast EU jet fuel consumption of around 46 Mt.
- The trajectory rises to 70% by 2050, with a sub-mandate for synthetic e-fuels (Power-to-Liquid or PtL fuels, made from low-carbon hydrogen and captured CO₂ rather than waste oils) starting at 0.7% in 2030 and reaching 35% by mid-century.
The feedstock side is narrower than the headline numbers imply. EU Commission data show that 81% of SAF feedstock inputs in Europe in 2024 were Used Cooking Oil (UCO) collected from restaurants, food processors and households; animal fats accounted for around 17%. In the same year, 25 fuel suppliers supplied SAF to 33 EU airports across 12 Member States, with airports in five Member States (France, Germany, the Netherlands, Spain and Sweden) accounting for 99% of supply. UCO is, in effect, the workhorse of European SAF.
Modelling places truly collectable UCO at 3 to 8% of projected SAF demand by 2030 even under ambitious collection scenarios. Indicative bulk UCO prices have risen into the $750 to $1,250 per tonne range, with spikes above $1,400 per tonne in constrained import markets. For context, conventional Jet A-1 traded around $700 to $1,000 per tonne before the recent crisis.
What the Hormuz closure changed, and what it did not
The Strait of Hormuz is a narrow shipping channel at the entrance to the Persian Gulf. It carried roughly 20% of global oil and a substantial share of jet-fuel exports before the regional conflict began at the end of February 2026. Vessel traffic has been effectively curtailed since the beginning of March. Saudi Aramco reported on 11 May 2026 that two to five tankers pass daily through Hormuz against around seventy before the conflict, with more than 600 ships stranded in the Gulf and around 240 waiting outside the Strait. The International Energy Agency (IEA) has characterised the disruption as the largest supply event in the history of the global oil market. Jet fuel prices in Western Europe hit successive record highs, with the Platts jet CIF NWE cargo assessment reaching $1,842.50 per tonne on 2 April 2026, and Airports Council International Europe warned on 9 April that the EU would face a “systemic jet fuel shortage” if the Strait did not reopen within three weeks. It has not.
Hormuz does not move material volumes of SAF feedstock or finished SAF. European SAF is overwhelmingly UCO-based, with imports routed primarily from Asia via the Suez Canal and the Mediterranean. There is no SAF refining capacity inside the Gulf at scale. In that narrow physical sense, the closure does not interrupt SAF supply. The crisis interacts with the SAF market through three indirect channels.
Channel 1: blend-stock and infrastructure overlap
No commercial aircraft today flies on 100% SAF; every approved uplift is a blend with conventional Jet A-1, capped at 50% under current certification and in practice usually well below. Disruption to Jet A-1 availability therefore directly affects the volume of finished fuel that can be loaded into an aircraft, regardless of how much SAF is technically available. The same logic applies to logistics: the pipelines, terminals, into-plane fuelling agents (companies such as Air BP, Skytanking and Mabanaft, which physically pump fuel into aircraft on the apron) and airport hydrant systems handle SAF blends and conventional jet through the same pipes. Refuelling restrictions imposed at four Italian airports (Bologna, Milan Linate, Treviso and Venice) between 2 and 9 April 2026, citing limited fuel availability from Air BP Italia and capping non-priority aircraft at 2,000 litres, illustrate how a conventional supply constraint becomes an operational constraint on all uplift, blended or otherwise.
Channel 2: hydrogen and process inputs
The HEFA process is hydrogen-intensive. Hydrogen is consumed in the reaction that removes oxygen from the fatty-acid feedstock and rearranges it into kerosene-like hydrocarbons. Most industrial hydrogen used today is “grey” hydrogen, produced from natural gas through Steam Methane Reforming (SMR), a high-temperature reaction between methane and water vapour that releases hydrogen and CO₂. Natural gas moves through the same trade flow as oil: the Hormuz closure has also constrained Liquefied Natural Gas (LNG) volumes from Qatar and other Gulf exporters (QatarEnergy declared force majeure on a number of long-term LNG contracts, including buyers in Italy, Belgium, South Korea and China, after halting production at Ras Laffan in early March), tightening European gas balances and lifting process-gas costs. PtL pathways are more dependent still, in their case on green hydrogen and large quantities of renewable electricity. The energy inputs to SAF production are not isolated from the oil-market shock.
Channel 3: feedstock market dynamics
Used cooking oil is a globally traded commodity, and the most consequential 2026 movements on the feedstock side are not primarily Hormuz-driven. China, the world’s largest UCO producer, tightened export controls in early 2026 and is bringing significant domestic SAF capacity online, including PetroChina’s first dedicated SAF unit at the Huabei Petrochemical refinery, with a 100,000-tonne-per-year HEFA capacity targeted for late 2026. Indonesia is advancing a B50 biodiesel blend programme in the second half of 2026 that will absorb additional UCO domestically. The combined effect is upward pressure on seaborne UCO prices into Europe, independent of the Gulf crisis but compounding with it.
Compliance obligations under ReFuelEU
The regulation has not been relaxed. The 2% SAF mandate for 2025 remains in force, scaling to 6% in 2030 and 70% in 2050. The 90% fuel-uplift rule, designed to prevent airlines from “tankering” (flying into the EU with extra cheap fuel loaded elsewhere to avoid taking on more expensive EU fuel), admits exemptions only in narrow cases, such as a confirmed jet-fuel shortage at a specific airport supported by an official notice. Higher fuel or SAF prices are not valid grounds.
The operational consequence is a layered cost position. Airlines must continue meeting a SAF blend obligation priced at the high end of recent history, while paying record prices for the conventional fuel that still makes up most of every uplift, with limited flexibility to optimise the system by tankering. Carriers have responded with capacity cuts. The Lufthansa Group has announced the removal of approximately 20,000 short-haul flights through October 2026, representing about 40,000 metric tonnes of jet fuel and roughly 1% of the Group’s Available Seat Kilometres (ASK). The Group has cited fuel costs alongside its CityLine subsidiary closure and German airport site costs as drivers. Ryanair has separately forecast 5 to 10% summer cancellations if Hormuz remains closed.
What this looks like in Bremen
The technical linkages above are global, but they have a local signature. Bremen’s aerospace cluster (more than 140 companies, 20 research institutes and roughly 12,000 employees, the highest aerospace employment density in Germany) depends on same-day intercontinental connectivity through Frankfurt and Munich. That connectivity is being recompressed by the same airline economics described above. On 10 May 2026, Lufthansa announced that its Bremen to Frankfurt service will end on 1 July, citing rising costs and changed operating conditions; the route currently operates around 35 weekly rotations and carries more than 5,000 passengers a week, the majority connecting onto intercontinental flights. The cut sits alongside the Group’s 20,000 short-haul flight removal, the permanent shutdown of Lufthansa CityLine on 18 April 2026 (27 aircraft grounded), and the early retirement of the last four Airbus A340-600 widebodies in October 2026, ahead of their previously planned retirement.
The carrier attributes these measures to a combination of fuel-cost pressure, the closure of its CityLine regional subsidiary, and German airport site costs, not to the Hormuz situation alone. But the fuel-cost arithmetic discussed in this article is one input into a decision that has, in this case, removed Bremen’s most important hub connection. The local impact is therefore a useful illustration of how a global fuel-system event materialises in a specific industrial region.
Parameters to monitor
For our DGLR community tracking the technical evolution of the situation, several measurable indicators carry more information than headline price quotes:
- The SAF premium over Jet A-1 in Northwest European spot markets. A narrowing premium reflects oil-market repricing, not improving SAF economics.
- Operational SAF capacity additions versus the announced 2030 trajectory, particularly delays to permitted European HEFA plants.
- UCO seaborne import prices into Rotterdam and Antwerp as a proxy for Asian feedstock availability.
- Throughput on the Saudi East/West pipeline (Petroline), recently ramped to a reported 7 million barrels per day as a Hormuz bypass for Gulf crude.
- Pipeline, terminal and hydrant capacity utilisation at major European airports as a signal of into-plane supply tightness independent of price.
What 2026 has made visible is not two separate situations running in parallel, a Hormuz shock and a SAF shortage, but a single, increasingly coupled fuel system in which a hydrocarbon supply event propagates through pricing, infrastructure, hydrogen inputs and feedstock markets, compressing the operating envelope for conventional and sustainable aviation fuel at the same time. The two-horizon framing of our January seminar (SAF in the near term, hydrogen across the longer one) remains the right strategic map. The near-term horizon has simply narrowed faster than expected, and the visible local effects, including, among other reasons, the loss of Bremen’s most important hub connection, are now part of the picture our community has to read.
From DGLR Bremen, we hope that global supply chains will reorganise at a pace closer to the speed at which they were disrupted, and that the conditions for the SAF ramp-up Europe needs are restored as quickly as the underlying situation allows.