Generating hydrogen from renewable energy
Each molecule of water contains two elements: hydrogen and oxygen (which is why chemists write water as H2O). It's a very stable molecule – it likes to stay as it is, so splitting it into its components requires energy to be put in. The machine to do that is called an electrolyser. It takes in water, safely passes electricity through it, then collects the hydrogen and oxygen that is made. (Surf 'n' Turf only uses the hydrogen. The pure oxygen is released back to the atmosphere.)
The EMEC electrolyser that Surf 'n' Turf has access to is known as a Proton Exchange Membrane type. PEM electrolysers are well suited to this setup, because they can handle variable energy inputs more readily than other electrolyser technologies. That's important to work successfully with the renewable energy sources Surf 'n' Turf is connecting it to.
The EMEC electrolyser is rated at 500kW. That means it can take over half the entire output of the 900kW ERE wind turbine, when that is curtailed, to keep it turning when otherwise it might have to stop or run slow.
The hydrogen is compressed and stored at the EMEC site, until the Surf 'n' Turf project needs to transport fuel to Kirkwall.
A photo gallery of the electrolyser and other related hydrogen generation technologies. Images courtesy of ITM Power