RE: FT article on energy storage23 Nov 2020 18:12
NewYorkSaint - any asset is only as good as the use you get out of it.
In the case of tidal flow the strength of the tidal flow varies between zero and a maximum 4 times a day. If you were to size an electrolyser for the maximum power then you could only use it for 50% of the time. The VRFB, or any battery, allows that fluctuating power to be smoothed out so that it is constant. This allows the H2 electrolyser to be sized for only half of the maximum, and used 100% of the time.
This is clearly more efficient as it saves on half the cost of the electrolyser even if it were not for the following point :- Electrolysers, I understand, also like to be run at continuous power, and not ramped up and down.