100% renewable targets will require power storage to manage flows on the net
Electrolysers utilise these intermittent power flows to produce H2 gas from water
H2 gas can be stored in large quantities underground and transported via existing gas pipelines
H2 vehicles recharge faster and are more durable than battery powered transport
Growing H2 demand in industrial processes will reduce costs and increase supply

To make the fluctuating power production from windmills more useful for the Danish society certain plants are needed for the conversion of this power into other energy forms that can be stored. Storing energy means that power will be available at all times – also when the windmills are not running due to less wind or extreme weather conditions.

The most efficient way of converting surplus power production into useful fuels is electrolysis. In electrolysis the electricity is used for splitting water (H2O) into oxygen (O2) and hydrogen (H2). This hydrogen can then be stored in the existing gas network or used for fuel cell vehicles. In addition to this, hydrogen may be used for upgrading biogas to methane-quality and thus making it storable in the gas network.

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