Sustainable Ammonia Production from U.S. Offshore Wind Farms: A Techno-Economic Review

Ammonia production with offshore wind power has the potential to transform energy and fertilizer markets within the United States. As summarized in this paper, the offshore wind resource can be converted directly into liquid ammonia using state-of-the-art technologies. The liquid ammonia can either be used as a fertilizer or a fuel. This work reviews the technologies required for all-electric, wind-powered ammonia production and offers a general design of such a system. Cost models based on the physical equipment necessary to produce ammonia with wind power are developed; offshore wind farm cost models are also developed for near-shore, shallow, wind farms in the United States. These models are capable of calculating the capital costs of small, industrial-sized ammonia plants coupled with an offshore wind farm. A case study for a utility-connected, all-electric ammonia plant in the Gulf of Maine is used to assess the lifetime economics of such a system. The results show that significant utility grid backup is required for an all-electric ammonia plant built with present-day technologies. A sensitivity analysis showed that the total levelized cost of ammonia is driven in large part by the cost of producing electricity with offshore wind.