EMEC hydrogen storage cylinders (Credit Colin Keldie)

Hydrogen R&D facilities

EMEC has established a green hydrogen R&D ecosystem to demonstrate the value chain from production and storage to transportation and end use.

The R&D ecosystem has been at the centre of a number of hydrogen innovation projects which are testing and demonstrating green hydrogen production and storage systems, as well as enabling the development of logistics solutions to transport hydrogen to other islands in the archipelago and the UK mainland for use in end applications across power, heat and transport.

EMEC’s strategic R&D focus areas are hydrogen innovation to increase renewable integration, and hydrogen research and demonstration in the aviation and maritime sectors. For further information on how our hydrogen infrastructure and knowledge can support your green hydrogen project, visit hydrogen R&D services and hydrogen projects.

Hydrogen transport map


Hydrogen production

EMEC own and operate both fixed and re-deployable hydrogen production assets.

The fixed hydrogen production plant is located onshore in Eday neighbouring EMEC’s grid-connected tidal test site at the Fall of Warness. The production plant is integrated with renewable energy input, either tidal energy converters testing at the Fall of Warness or from the Eday community wind turbine. The plant will shortly be integrated with flow battery technology to optimise hydrogen production by ‘smoothing’ tidal generation to create continuous, on-demand electricity to power EMEC’s electrolyser.

EMEC’s re-deployable electrolyser supports demonstration projects by providing on-site hydrogen generation in locations where there is no fixed hydrogen infrastructure.

Electrolyser and static storage

EMEC’s hydrogen production plant includes a 670 kW rapid response PEM (Proton Exchange Membrane) electrolyser which produces ‘green’ hydrogen using locally-produced renewable energy. Control switchgear inside EMEC’s substation determines whether the power fed to the electrolyser is to be routed from tidal generators testing at the Fall of Warness site or the 900 kW community wind turbine nearby. The electrolyser is capable of ramping up and down flexibly to take advantage of variable renewable generation.

The electrolyser is housed in a standard 20′ by 10′ ISO container and has the capability of generating up to 260 kg of high purity, fuel cell grade hydrogen per day based on the electrolyser running at full power for 24 hours.

Hydrogen gas is produced via electrolysis at 20 bar. A compressor then further pressurises the gas to 200 bar at which point it is stored. Up to 500 kg of hydrogen can be stored in onsite storage cylinders.

In 2017 EMEC achieved the world’s first tidal generated hydrogen using power from tidal energy clients, Orbital and Tocardo, who were testing tidal energy devices on site.

Vanadium Flow Batteries | Energy Storage 

Located adjacent to the hydrogen laydown area, EMEC’s energy storage building houses 48 vanadium flow battery (VFB) modules with a combined storage capacity of 1.8MWh.

Once fully integrated, a unique combination of tidal power and flow batteries will power EMEC’s hydrogen production plant aiming to optimise green hydrogen production capacity from variable renewable generation.

VFBs are well suited as a storage solution for tidal power production as it can cope with the heavy charge and discharge cycles that comes with 4 tidal cycles per day. Vanadium also does not degrade as quickly as lithium-ion technology.

Re-deployable electrolyser

EMEC operate a re-deployable modular electrolyser which can used for on-site small scale hydrogen generation in locations with no fixed production infrastructure.

Housed in a container, the unit consists of 10 stack anion exchange membrane (AEM) electrolyser technology and a low-pressure buffer tank. The electrolyser is rated at 24kW and generates hydrogen at 30 – 35 bar which is then stored in the low-pressure buffer tank.

The re-deployable electrolyser can be coupled with our mobile refuelling solution to offer an end-to-end system.

Hydrogen transportation and refuelling

Mobile storage trailers

Specially designed mobile hydrogen storage trailers transport hydrogen from point of production via road and ferry to a variety of end applications across power, heat and transport in technology demonstration projects.

Each trailer can transport 250 kg of hydrogen. The trailers consist of 59 lightweight composite cylinders made of aluminium with a Kevlar wrap, specially designed to comply with road restrictions.

To date the trailers have supplied hydrogen to demonstration projects on the Orkney mainland and on the UK mainland.

Mobile refuelling solution 

EMEC’s mobile, ADR-certified hydrogen refuelling solution, provides hydrogen refuelling capabilities to locations with no existing or fixed hydrogen infrastructure.

The mobile refuelling solution can be coupled with EMEC’s 24 kW re-deployable modular electrolyser for on-site hydrogen generation to offering a full end-to-end system.

The refuelling solution takes hydrogen gas and compresses it up to 450 bar and then stored 12 storage banks. It is capable of dispensing up to 20 kg hydrogen at 350 bar per operation.

Kirkwall Pier fuel cell:

EMEC own and operate a 75 kW fuel cell housed at Kirkwall Pier which can convert hydrogen back to electricity. The electricity can then be used to ‘cold iron’ local inter-island ferries while berthed overnight at the pier.
Designed to resemble the vessel engine room of a ship, the fuel cell can be used as a training rig as part of a first of a kind MCA-approved hydrogen training course. The course was developed by Orkney College UHI’s Maritime Studies department in collaboration with EMEC and Orkney Ferries to equip mariners with the necessary skills and knowledge to work on-board hydrogen fuelled vessels.

Combined Heat & Power (CHP)

A combined heat and power (CHP) unit has been installed at Kirkwall Airport to demonstrate the use of hydrogen for heat and power requirements in the airport terminal building. Once fully commissioned, the CHP will be operated and maintained by EMEC.


EMEC’s hydrogen R&D facilities are overseen by experienced maintenance and operation technicians with infrastructure regularly checked and tested.

Safety is paramount and as hydrogen gas is flammable, it needs to be treated with care.  Appropriate safety measures and procedures are in place on our sites to minimise any associated risk with all equipment designed to let gas safely disperse upwards into the atmosphere, were a leak ever to occur. The infrastructure on site has been tested to UK and European standards and regular safety inspections are carried out by EMEC to ensure equipment is operating correctly.








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