The CO2 emissions from the grid-electricity generation were also taken into account. In other words, the daily PV electricity allocated for ammonia synthesis was further subdivided into 24 hours of water generation from seawater and water electrolysis to obtain the hydrogen amount required for ammonia synthesis, and 4.5 hours of nitrogen separation and ammonia synthesis. The electricity from the grid was assumed to be two patterns: thermal power generation based on natural gas and coal, where the output is readily controlled. The LCCO2 emission factor for the electricity generation, 𝐶 .