A net-zero world would require 306 million tonnes of green hydrogen to be produced annually by 2050, according to the International Energy Agency (IEA).

Stay ahead on hydrogen with our free newsletter
Keep up with the latest developments in the international hydrogen industry with the free Accelerate Hydrogen newsletter. Sign up now for an unbiased, clear-sighted view of the fast-growing hydrogen sector.

That would require something in the region of 3,000GW of electrolysers and 6,000GW of renewable energy, based on current technology.

Considering the world had only installed 3,371GW of renewables by the end of last year (according to the International Renewable Energy Agency [Irena]) — and that the planet will need about 30,000GW of renewable energy to decarbonise the global electricity supply, that’s a fairly tall order.

Based on the notion that economies of scale would reduce the cost of green hydrogen production, several developers have announced massive and extremely ambitious projects that aim to meet much of the world's future demand for clean H2.

Hydrogen Insight has compiled a list of the 11 largest renewable H2 projects yet announced — based on data exclusively provided by research house BloombergNEF (BNEF), as well as publicly available information — which, if fully built out, would provide more than 100 million tonnes of green hydrogen a year, roughly a third of the amount the IEA says will be needed in 2050 to reach net-zero emissions.

While Western Europe is expected to be one of the biggest demand centres for renewable H2, none of the listed projects are based in this region, although multiple one-million-tonnes-a-year projects such as Denmark’s BrintØ and the Netherlands’ NortH2 are in development on the continent.

Similarly, although the US has been cited as a top priority for clean hydrogen investment based on the offer of a generous tax credit of up to $3/kg, only one project — Green Hydrogen International’s Hydrogen City complex in Texas — ranks among the top 11.

Canada, Egypt, Australia, and Mauritania each have two projects on the list, with the rest spread between Oman, Mozambique and Kazakhstan.

Put simply, green hydrogen projects of this kind of scale not only need to be built in places with strong winds and/or sunshine, but they will need an awful lot of land just to accommodate the amount of wind turbines and/or solar panels required.

Clearly, these projects are enormously ambitious, and there is still substantial doubt around whether any of them will go ahead as planned.

Indeed, some of them are so massive that they seem more like impossible dreams than realistic propositions.

For instance, the world's largest offshore wind farm is just under 1.4GW, but developer GHI wants to build two projects that each have 500GW of wind turbines installed at sea. To put that into context, only 63.2GW of offshore wind had been installed around the world by the end of 2022, according to Irena.

Both of those projects would require wind turbine and electrolyser factories to be built at almost unimaginable scales, not to mention dozens of new turbine installation vessels — we’re talking total investments adding up to more than a trillion dollars.

It is also worth noting that most of the projects listed below are at very early stages of development, and that they will still need regulatory approval, not to mention staggering amounts of funding. And if they do go ahead, they will almost certainly be built in phases.

So here’s our list of the world's 11 biggest green hydrogen projects, based on estimated annual H2 production (it was supposed to be ten, but there was a tie in tenth place):

1=) Spirit of Scotia Green Hydrogen Production Hub

Location: Nova Scotia, Canada

Developer: Green Hydrogen International, a Texas-based firm founded in 2019, which as of writing, has four employees listed on LinkedIn

Estimated annual production: 43 million tonnes

Electrolyser capacity: Unknown

Power source: 500GW of offshore wind

Planned use of H2: Export to European and North American markets

Development schedule: No timeline for final investment decision (FID), construction or operation has been disclosed, but the developer says it has secured 130,000 acres of storage-grade salt cavern rights across the Canadian province.

Expected cost: Not disclosed.

1=) Fleur-de-lys Green Hydrogen Production Hub

Location: Quebec, Canada

Developer: Green Hydrogen International

Estimated annual production: 43 million tonnes

Electrolyser capacity: Unknown

Power source: 500GW of offshore wind

Planned use of H2: Green ammonia, but unknown if meant for international or domestic markets

Development schedule: No timeline disclosed, although 40,000 acres of potential salt cavern storage have been secured.

Expected cost: Not disclosed.

3) Unnamed Nouakchott project

Location: Nouakchott, Mauritania

Developers: Infinity Power Holding (a joint venture between the UAE’s Masdar and Egypt’s Infinity) and Germany’s Conjuncta

Estimated annual production: 8 million tonnes of hydrogen and its derivatives, although the developers have not clarified the exact H2 production capacity given the differing weights of hydrogen, ammonia, methanol and other derivatives.

Electrolyser capacity: 10GW in full phase

Power source: Not revealed

Planned use of H2: Export to Germany, although no agreements to this effect have been signed.

Development schedule: The first 400MW phase is due to start operations by 2028, but timelines for scaling up have not been disclosed.

Expected cost: $34bn

4) Western Green Energy Hub

Location: Western Australia, specifically, the Goldfields-Esperance region in the southeast of the state

Developers: InterContinental Energy (based in Singapore), CWP (founded in Serbia), the Mirning Traditional Lands Aboriginal Corporation, and potentially South Korean power company Kepco

Estimated annual production: 3.5 million tonnes

Electrolyser capacity: 35GW (BNEF estimate)

Power source: 50GW of wind and solar

Planned use of H2: Unknown, although co-developer Kepco, which signed a memorandum of understanding to co-develop the project in July, is already exploring imports of ammonia and hydrogen to South Korea for co-firing in existing fossil-fuel-fired power plants.

Development schedule: Site assessment is ongoing, with FID due in 2027.

Expected cost: Not disclosed.

5) Hydrogen City

Location: Texas, with pipelines to deliver H2 to the port of Corpus Christi

Developer: Green Hydrogen International

Estimated annual production: 3 million tonnes

Electrolyser capacity: Unknown

Power source: 60GW of onshore wind and solar

Planned use of H2: Export to Asia as green ammonia, feedstock for fertilisers, sustainable aviation fuel and rocket fuels, and co-firing in domestic power plants.

Development schedule: A first phase, drawing on 2GW of upstream renewables and using two salt caverns for storage, is due to start operations in 2026, but no timeline has been given on when the full phase will start construction.

Expected cost: Not disclosed.

6) Unnamed SCZONE Ain Sokhna project

Location: Ain Sokhna, in Egypt's Suez Canal Economic Zone

Developer: ACME, an Indian renewables developer

Estimated annual production: 2.1 million tonnes

Electrolyser capacity: 18GW (BNEF estimate)

Power source: Not revealed

Planned use of H2: Unknown, but would probably used for refuelling ships passing through the Suez Canal and/or exports

Development schedule: Construction of an initial 100,000 tonnes-a-year pilot is reportedly due to kick off in early 2024, but no firm date on start of operations of the full project.

Expected cost: $12-13bn (although this may only refer to the cost of the pilot)

7) Hyrasia One

Location: Kuryk, Kazakhstan

Developer: Hyrasia One (a subsidiary of German developer Svevind)

Estimated annual production: 2 million tonnes

Electrolyser capacity: 20GW

Power source: 40GW of wind and solar built in the country’s southwestern steppes

Planned use of H2: Export as ammonia, probably to Europe (via pipeline)

Development schedule: FID is due in 2026, with first production expected in 2030 and full capacity onstream from 2032. Preliminary studies were kicked off in June, and an investment agreement has already been signed with the Kazakh government.

Expected cost: $40-50bn

8=) Green Energy Oman

Location: Duqm, Oman

Developers: Oil major Shell, Intercontinental Energy, Omani state-owned oil firm OQ, and Kuwait-based EnerTech Holdings

Estimated annual production: 1.8 million tonnes

Electrolyser capacity: 14GW (BNEF estimate)

Power source: 25GW of wind and solar

Planned use of H2: Domestic use and export as ammonia to international markets

Development schedule: FID after 2026, although it is unclear whether this refers to the first phase powered by 4GW of renewables (for which the consortium had been awarded land in the Oman’s first green H2 auction) or the full production capacity.

Expected cost: Not disclosed.

8=) Aman

Location: Northwest Mauritania

Developer: CWP

Estimated annual production: 1.8 million tonnes

Electrolyser capacity: Unknown

Power source: 30GW of renewables (18GW wind and 12GW solar)

Planned use of H2: Local use and export, with 50 million cubic metres of additional desalinated ocean water supplied to nearby communities and agriculture.

Development schedule: Unknown, although a framework agreement has been signed with the Mauritanian government.

Expected cost: $40bn

10=) Unnamed Mozambique project

Location: Inhambane, southern Mozambique

Developers: UK-based Jearrard Energy Resources, founded in 2021

Estimated annual production: 1.6 million tonnes

Electrolyser capacity: Not disclosed

Power source: 12GW of solar power

Planned use of H2: Mainly export to Europe, some volumes to be used in Mozambique and neighbouring countries

Development schedule: Construction to kick off in mid-2024, but start of operations unknown.

Expected cost: Not disclosed.

10=) Australian Renewable Energy Hub

Location: The Pilbara region in the north of Western Australia

Developers: Oil major BP, Australian-headquartered bank Macquarie, InterContinental Energy, and CWP

Estimated annual production: 1.6 million tonnes

Electrolyser capacity: Estimated to be 14GW

Power source: 26GW of wind and solar

Planned use of H2: Domestic markets and export, as well as supplying renewable power directly to the local customers.

Development schedule: At the end of 2022, BP’s then chief financual officer (and now-interim CEO) Murray Auchincloss described bringing the first phase serving the domestic market on line between 2025 and 2027, with the full export hub to start production “by the end of the decade”.

Expected cost: Not disclosed.

Note: We have not included the 67GW, 3.6-million-tonnes-a-year HyDeal Ambition project in this list, as it would actually consist of several smaller projects across Spain, France and Germany, and there is no information available about those individual projects.

Updated on 27 November to clarify the production capacity of the Nouakchott project refers to both hydrogen and its derivatives.