A techno-economic comparative analysis of thermal oil and molten salt parabolic trough power plants with molten salt solar towers

This study presents a comparison between thermal oil and molten salt parabolic trough power plants as well as molten salt solar towers. Although higher temperature differences in solar towers enable higher power cycle efficiencies, the necessity of large solar fields for increasing turbine capacities and capacity factors pose a limitation through increased attenuation losses. This effect is amplified when unfavourable atmospheric conditions with visibilities of e.g. 15 km are present to the extent where 200 MW parabolic trough power plants with molten salt as heat transfer fluid can achieve lower levelised costs of electricity and higher capacity factors than solar towers. Additionally, solar towers require a significantly larger solar field and thus land area as compared to molten salt parabolic through power plants. Moreover, both molten salt parabolic troughs and solar towers outperform thermal oil parabolic trough systems in terms of LCOE and capacity factors.