The project “Verbundvorhaben CF06_2: Development of a concept for a functional prototype for the decentralized production of green ammonia” was carried out from 1 April 2020 to 31 January 2023 with funding from the German Federal Ministry of Education and Research (BMBF). The consortium, led by ZBT GmbH, aimed to design a plant that integrates 16 MW of wind power, 16 MW of photovoltaic (PV) capacity and a 16 MW electrolyzer located in Mecklenburg‑Vorpommern. The core technical deliverable was a simulation model of the complete ammonia synthesis loop, built in the Ebsilon platform and later refined with Aspen+ for dynamic process modelling.

Using nine years of hourly data (2010‑2019) from the local wind and solar parks, the study quantified the availability of renewable electricity. Wind and solar together covered about 92 % of all load cases up to 19 MW, roughly half of the installed capacity. Dark periods were 10 % for wind and 50 % for solar, underscoring the need for storage or flexible operation. The electrolyzer’s input was found to be 35 % below its theoretical maximum, indicating that the plant would be well utilized under the chosen configuration. Sensitivity analyses identified operating pressure, reactor temperature, electrolyzer Faraday efficiency, compressor efficiency and ambient temperature as the most influential parameters on overall plant efficiency. By calibrating the reactor model with ruthenium‑based catalysts and flow‑guide elements, the spread in predicted efficiency could be narrowed, enabling more accurate load‑point calculations.

The simulation predicted a maximum annual ammonia production of 3 500 t a⁻¹. The plant concept was iteratively refined to optimise load spread and standby operation, balancing energy savings against economic viability. Real‑world components were substituted for idealised models to assess practical performance, and the resulting design was coupled to the renewable energy time series to estimate yearly output and profitability. The final concept incorporates a flexible process flow diagram, a high‑temperature electrolyzer model with a detailed U(I) curve, and a dynamic off‑gas handling scheme, all of which are intended to support decentralized, low‑carbon ammonia production.

The consortium’s roles were clearly delineated: ENERTRAG SE generated the overall concept (CF06_2.1), ZBT developed the process flow diagram (CF06_2.2), Sunfire GmbH handled hydrogen production (CF06_2.3), and the Institute for Climate Protection, Energy and Mobility (IKEM) managed permitting procedures (CF06_2.4). The short report, dated 20 July 2023, summarizes the technical findings and confirms that the plant design meets the project’s objectives of integrating variable renewable energy into a robust, decentralized ammonia synthesis system.