An Evaluation of a High Altitude Solar Radiation Platform

This paper presents a preliminary assessment of the potential advantage that a high altitude solar collector could bring compared with the traditional ground based photovoltaic systems. This advantage mainly derives from the reduced attenuation of the solar radiation as it travels through the atmosphere especially if clouds are present above the location considered. A sun beam traveling through clear atmosphere is considered first using an existent model to calculate the daily irradiation at different altitudes in clear sky conditions. The results obtained are then integrated with experimental data describing cloud distributions versus altitude, and finally the contribution of the diffused radiation is also included to give a realistic evaluation of the total actual irradiation at a specific altitude. The results are obtained for a specific location in the UK, where the experimental data have been acquired. The general conclusions, however, involving the potential of high altitude solar collectors, can be extended to other countries in Europe with similar climates. Finally, the main issues involved in the design and development of a flying platform for the exploitation of the solar energy are presented and the technical feasibility of the system is discussed.