World Map of Low-Layer Atmospheric Extinction Values. Overview of Its Impact on Solar Power Tower Plants Projects

In this paper, we present a world map with annual average values of low-layer atmospheric extinction. It is the first of its kind and contains helpful information for the improvement and evaluation of concentrating solar power tower plant projects. To reduce the computational time for world mapping, the methodology developed and validated in 2021 for the elaboration of the map of Chile has been improved. The improvement presents a 2% error in comparison with the original methodology. The world map has been elaborated processing the 30 years hourly values of atmospheric parameters provided by MERRA-II in each of the 31,560 pixels existing between the latitudes of 35N and 35S. Global daily averages of atmospheric extinction are between approximately 3% and 30%, implying annual energy losses in solar power tower plants of between 3% and 30%. The southern hemisphere is characterised by low extinction values, while hight attenuation values are found in the northern hemisphere, reaching values of 30% in some places.Low-layer atmospheric extinction has a high impact on the economic evaluation of solar tower projects. In the case of the LCOE, it is necessary to correct upwards the calculated values without considering the energy losses due to atmospheric extinction.