Decarbonisation Technology - February 2024 Issue

Hydrogen FCEV/FCEB

Hydrogen ad-mixing into natural gas pipeline

Synthetic fuels via Fischer - Tropsch

Fuel cell

Wind

Desulphurisation of fossil fuels

Hydro power

Gas turbine

Upgrading biofuels

Hydrogen storage/ distribution

Electricity grid

Battery

Biomass

Gasication

Invertor

Methanol

Rectier

Ammonia

Other end use

Metals rening

Solar PV

Hydrogen electrolyser

Figure 1 Renewable hydrogen production, distribution, storage, and utilisation value chains

Some of the renewable power modes are more than variable, they are intermittent, meaning that power generation falls to zero for periods of time. Alkaline electrolysers are the cheapest technology to purchase, but they do not cope well with unplanned shutdowns. They prefer that a minimum protective current is permanently flowing. This avoids corrosion of the electrodes and degradation of electrolysis efficiency. High-capacity batteries can be integrated into the power supply system to ensure a trickle of power flows during periods of no wind or sunlight. Alternatively, power can be drawn from the grid to complement the renewable power generation. However, using grid power may undermine the ‘green’ credentials of the hydrogen and reduce its marketability. There are only a few locations, such as the Magallanes in southern Chile, where the wind blows steadily throughout the year. These advantaged locations can offer high electrolyser utilisation based on wind-only renewable power supply schemes. Most other locations would seek to integrate wind and solar power to

balance the variability of these two sources. Green hydrogen superpowers of the future will be nations or regions that have ideal conditions for integrated wind and solar. The perfect conditions for green hydrogen electrolysis are locations where the wind picks up during the late afternoon and blows steadily through the night until the sun rises at dawn. Southern Chile, western Namibia, and the east coast of Oman stand out as excellent green hydrogen production locations. West Australia, north-western Saudi Arabia, north-eastern Egypt, and parts of northern and western China are also blessed with ideal conditions for integrated wind and solar power generation. However, in each of these locations, the rainfall is neither sufficient nor steady enough to provide water for large-scale electrolysis. Desalination for green hydrogen projects on the Red Sea coast Helios is the world’s first GW-scale green hydrogen project to be announced and taken through to Final Investment Decision (FID). It is sponsored by Air Products, ACWA Power, and