The pattern in one line: India's port-based green-fuel infrastructure is real but tiny — a 10 Nm³/hour hydrogen pilot, a handful of PPP-stage jetty approvals, and one certified bunkering trial — while the regulatory rulebook built to govern it, DGS Circular 32/2025, is unusually detailed for something with almost nothing yet to regulate. That gap between paper-readiness and physical scale is itself the story: India is writing the rules before the market exists, rather than catching up to one already running.

International shipping has its own binding decarbonisation timetable. The International Maritime Organization's Net-Zero Framework sets a "base target" requiring a 4 per cent cut in ships' GHG Fuel Intensity (GFI) by 2028, rising to 30 per cent by 2035, alongside a stricter "direct compliance target" of 17 per cent by 2028 rising to 43 per cent by 2035 for vessels that want to avoid the framework's economic penalties. A pricing mechanism attached to the framework applies to a share of international shipping emissions starting in 2028, with an initial carbon price of $100 per tonne of CO2. None of this mandates biofuel or hydrogen specifically — ammonia, methanol, and LNG are all competing alternative marine fuels — but it is the regulatory pressure that makes every one of the Indian pilots below commercially rational rather than purely aspirational.

Set against the two ports that already dominate global marine biofuel bunkering, India's position is stark. Combined bio-blended bunker fuel sales at Singapore and Rotterdam rose from roughly 300,000 tonnes in 2021 to more than 1.6 million tonnes in 2024; Singapore alone supplied about 0.88 million tonnes of biofuel blends in 2024, with commercial availability up to B50 and trials extending to B100. India's first port-based green hydrogen plant, commissioned at V.O. Chidambaranar (VOC) Port, Tuticorin, and inaugurated by Union Minister Sarbananda Sonowal, produces 10 normal cubic metres of hydrogen an hour — and, per the inaugurating ministry's own framing, that hydrogen currently powers streetlights and an EV charging station in the port colony, not ships. Run continuously for a full year, a 10 Nm³/hour electrolyser would produce on the order of 8 tonnes of hydrogen — a scale comparison across different fuel types (hydrogen versus blended biodiesel) that is not apples-to-apples, but is nonetheless a useful illustration of just how early-stage India's port-based green-fuel production still is next to an established bunkering hub.

Hydrogen and blended biodiesel are different fuels with different energy content and cannot be summed directly; this table is included to show relative scale of activity, not a like-for-like fuel comparison.

In October 2025, the Ministry of New and Renewable Energy formally recognised three ports — Deendayal Port Authority (Kandla, Gujarat), V.O. Chidambaranar Port Authority (Tuticorin, Tamil Nadu), and Paradip Port Authority (Odisha) — as green hydrogen hubs under the National Green Hydrogen Mission. Each is at a different stage of build-out. Deendayal Port has commissioned a 1 MW electrolyser-based green hydrogen plant and, separately, Greenzo Energy India Limited has been contracted to build a 5 MW green hydrogen facility at Kandla under the Sagarmala programme — described as the first such facility at an Indian port, scalable to 10 MW, with expected output of roughly 800 tonnes of hydrogen a year. Paradip Port Authority is developing a dedicated jetty for handling green hydrogen, green ammonia, and other liquid cargo, with capacity for up to 4 million tonnes per annum; the Ministry of Ports, Shipping and Waterways approved this project in February 2026 at an estimated cost of ₹797 crore, to be built on a build-operate-transfer, public-private-partnership basis. VOC Port, beyond its streetlight-scale hydrogen pilot, has separately had a Green Methanol Bunkering and Refuelling Facility approved — 750 cubic metres of storage capacity, ₹35.34 crore in cost — explicitly positioned as part of a proposed Coastal Green Shipping Corridor linking Kandla and Tuticorin, and intended to make VOC Port "a key green bunkering hub in South India."

The gap between the streetlight-scale hydrogen pilot and the much larger, PPP-structured jetty and methanol projects is the clearest signal of where India's port green-fuel strategy actually sits: the hydrogen-electrolysis pilots are proof-of-concept demonstrations, while the real bunkering-scale infrastructure being built is centred on green methanol and ammonia rather than hydrogen itself — consistent with the wider shipping industry's preference for liquid, energy-dense fuels that don't require the cryogenic or high-pressure storage hydrogen does.

On 2 April 2026, Kandla conducted what is reported as India's first Shore-to-Ship Methanol Bunkering Trial, certified by classification society DNV, explicitly framed against the Rotterdam–Singapore shipping corridor — the same corridor that carries the bulk of the world's established biofuel bunkering volume referenced in Section 2. Separately, Deendayal Port Authority has been assessed at a Port Readiness Level (PRL) of 6, progressing toward 7, for bio-methanol bunkering operations — an assessed institutional and infrastructure readiness score (broadly analogous in concept to a Technology Readiness Level, though applied to port operations rather than a single technology) rather than a measure of actual fuel throughput. A PRL score signals that the port authority, procedures, and safety systems are maturing toward routine commercial bunkering; it does not by itself mean commercial-scale bunkering is happening yet.

Underneath these pilots sits a genuinely new document: DGS (Engineering) Circular No. 32 of 2025, "Biofuel Bunkering Guidelines," issued by India's Directorate General of Shipping on 22 July 2025 and signed by Mahesh Korade, Engineer & Ship Surveyor cum Deputy DG (Technical). It is India's first dedicated regulatory framework for supplying biofuels — FAME, FAEE, straight vegetable oils, hydrotreated vegetable oil, bio-Fischer-Tropsch diesel, and biomass-to-liquid fuels, in blends up to B30 — as marine bunker fuel, covering tank-truck-to-ship, shore-to-ship, and ship-to-ship transfers at all Indian ports, anchorages, and territorial waters, for both Indian and foreign-flagged vessels.

The circular's own text is explicit that it is filling a real regulatory gap, not formalising an existing practice: it states that biofuel bunkering in India is "at a nascent stage," that "large-scale adoption remains constrained due to the absence of a unified regulatory framework," and that existing rules under MS Notice 14 of 2023 covered the use of biofuels aboard Indian ships but not the bunkering (supply) operation itself. It builds directly on international rules rather than inventing new technical standards from scratch: it adopts the IMO's MEPC.1/Circ.917 interim guidance permitting biofuel blends up to 30 per cent by volume to be carried on conventional MARPOL Annex I-certified bunker vessels (above that threshold, the stricter chemical-tanker rules under MARPOL Annex II and the IBC Code apply instead), and it cross-references ISO 8217:2024 marine fuel specifications, ISCC and RSB sustainability certification, and IMO safety codes including SOLAS and ISGOTT.

Registration process per DGS Circular 32/2025, Appendix 1, building on the existing Merchant Shipping Notice No. 03 of 2014 supplier-registration framework.

The operational detail goes well beyond paperwork. The circular specifies that biofuel transfer hoses must be pressure-tested at least every 12 months at 1.5 times maximum allowable working pressure, witnessed by an accredited inspector; that hose seals and elastomers be renewed at 50 per cent of their normal service life unless made from biofuel-compatible materials (fluorocarbon, nylon, Teflon, or Viton for elastomers; carbon steel, stainless steel, or aluminium for metal fittings in contact with biodiesel); and that every delivery carry a Bunker Delivery Note, an ISCC sustainability certificate, and a Certificate of Quality specific to the exact blend grade supplied (B20, B30, and so on), with blend ratios required to be transparent to all parties — and blending itself required to happen offsite, not aboard the receiving vessel, to ensure it is done properly. The circular was distributed to the Mercantile Marine Departments covering Mumbai, Kolkata, Chennai, Kandla, and Kochi, and to Surveyors-in-Charge at Goa, Jamnagar, Port Blair, Visakhapatnam, Tuticorin, Noida, Haldia, Paradip, and Mangalore — effectively the full list of ports where biofuel bunkering could plausibly begin under this framework, well beyond the three MNRE-designated hydrogen hubs.

A parallel, less visible piece of this build-out is on the vessel side rather than the port side. The underlying programme dates to February 2024, when the government issued scheme guidelines for pilot projects using green hydrogen in shipping, with an outlay of ₹115 crore (about $13.1 million) running through FY2025-26 under the National Green Hydrogen Mission, split between retrofitting existing vessels (led by the Shipping Corporation of India) and developing port-side bunkering and refuelling facilities for green hydrogen and its derivatives. Progress since then has moved from announcement to delivery: per India's Ministry of Ports, Shipping and Waterways, Cochin Shipyard and Mazagon Dock Shipbuilders have each now actually built one hydrogen-fuel-cell-powered vessel using indigenous technology — not merely started construction, as an August 2025 ministerial announcement had framed it. Cochin Shipyard's own hydrogen vessel is described as India's first hydrogen fuel-cell catamaran; the yard is separately building an autonomous electric ferry for a Norwegian customer, evidence its alternative-fuel vessel capability is being tested against export-market, not just domestic, requirements. Mazagon Dock's own near-term deliverable, signed with the Shipping Corporation of India in March 2026, is a different fuel altogether: a 3,000-tonne-deadweight platform supply vessel with methanol dual-fuel diesel-electric propulsion, built to Indian Register of Shipping classification rules and described as the first vessel in SCI's fleet to run on green methanol — a second, methanol-specific data point consistent with Section 3's observation that India's near-term bunkering infrastructure is centred on methanol and ammonia rather than hydrogen. Read against Section 4's shore-side infrastructure, the sequencing problem remains largely symmetric even with these deliveries: hydrogen- and methanol-fuelled vessels still need refuelling infrastructure that doesn't yet exist at commercial scale, and the hydrogen-producing ports don't yet have a fleet of vessels lined up to bunker regularly.