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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