UCL Report Links Green Ammonia to the Grand Inga Hydropower Project

A new report from the UCL Energy Institute argues that green ammonia could become a cheaper fuel than VLSFO for ships starting in 2035 under the International Maritime Organization's (IMO) Net-Zero Framework (NZF). The study, produced by the institute's Shipping and Oceans Research Group, uses the Grand Inga hydropower project in the Democratic Republic of Congo (DRC) as its case study and concludes that the regulatory framework could unlock renewable energy investment in developing countries.

The report assesses two applications of the electricity generated by Grand Inga for maritime decarbonization: supplying shore power to vessels berthed at DRC ports (cold ironing) and producing green ammonia via electrolyzers. Two plants are currently in operation, Inga 1 and Inga 2, with a combined rated capacity of 1,775 MW, and a third phase has been proposed with capacities ranging from 2 GW to 11 GW, for which the World Bank agreed last year to a multiphase financing package of $1 billion.

According to the report, total power demand for cold ironing at DRC ports is estimated at 21 GWh per year, equivalent to about 2.4 MW of average demand, which would avoid roughly 18,600 tonnes of CO2 equivalent annually. By contrast, a green ammonia production plant with a 580 MW electrolyzer operating at 90% capacity would generate 500,000 tonnes of ammonia per year, requiring 4,756 GWh of electricity annually according to Sea Trade Maritime, or approximately 4.6 TWh/year according to Safety4Sea—more than 200 times the demand of cold ironing. Under these assumptions, green ammonia could be produced at a delivered port cost of around $515 per tonne.

In terms of compliance-adjusted costs under the NZF, the report calculates that in 2030 Grand Inga's shore power would be the most competitive option, at a cost of -$36.6 per MWh, compared to $126.3 per MWh for green ammonia and $116.1 per MWh for VLSFO. The study notes that 2035 would be the first year in which green ammonia becomes cheaper than VLSFO on a per-MWh basis. By 2040, the adjusted cost of green ammonia would rise to $164.87 per MWh versus $179.57 for VLSFO, although without IMO policy incentives ammonia would cost $185.20 compared to $101.48 for VLSFO.

The authors warn that local demand for marine bunkering in the DRC, estimated at around 11,000 tonnes of ammonia per year, represents just 2.2% of the plant's projected capacity, meaning that exports and other markets, including fertilizer production, would be key to the project's viability. Researcher Jesse Ralph-Gbobo stated that the analysis shows strong potential for the NZF to unlock investment in electrification and in the power grid, while Dr. Mohd Shoaib noted that electrifying ships at berth is one of the cheapest ways to cut emissions and can contribute to the COP31 electrification goal. The report warns that a weakening of the NZF would undermine the business case for both cold ironing and green ammonia, as well as their contribution to renewable energy investment in developing countries.