Based on this trade-off, seawater desalination is advantageous until the elevation exceeds about 1500 m above sea level, while ammonia synthesis is favored at higher elevations. Also, at around 1500 m, LCCO2 emissions are approximately ±0, no matter how the PV power is distributed. Fig. shows a world map, with the areas below 1500 m elevation shown in blue. Except for some regions such as Peru, Chile, and Mexico, the coastal area within 200 km from the sea, the height usually is 1500 m. Therefore, the coastal deserts are worth considering for the WEA scheme.