  Converting wind energy into ammonia (WtA) has been recognized as a promising
pathway to enhance the usage of wind generation. This paper proposes a generic
optimal configuration model of WtA at the network level to minimize the ammonia
production cost by optimizing capacities and locations of WtA facilities
including wind turbines, electrolyzers, hydrogen tanks and optimizing supply
modes among regions. Specifically, the temporal fluctuation characteristics of
wind resources, the operation flexibility of the ammonia synthesis reactor and
the transport distances are considered. Three typical supply modes, i.e., the
Local WtA, the EN (electric network)-based WtA and the HSC (hydrogen supply
chain)-based WtA, combined with two energy transport modes including EN and HT
(Hydrogen truck trailers) are included with the consideration of the maximal
energy transport capacity of EN and transport distance per day of HT (500km).
Real data of Inner Mongolia (a typical province in China with rich wind
resources and existing ammonia industries) is employed to verify the
effectiveness and significance of proposed model. The effect of above
significant factors on optimal planning capacity of WtA facilities and optimal
energy transport modes is analyzed, which provides guidelines for WtA
configuration. The economic analysis shows that the average LCOA (levelized
cost of ammonia) for WtA is approximately 0.57 euro/kg in Inner Mongolia and
comparable to that for CtA (coal-to-ammonia, 0.41 euro/kg) with a reduction of
30% in capacity cost of the facilities.
