Defining an Annual Energy Output Ratio between Solar Thermal Collectors and Photovoltaic Modules

Photovoltaics (PV) and Solar Thermal (ST) collectors are sometimes competitors, as investment capacity, energy demand, roof space limited. Therefore, a ratio that quantifies the difference in annual output between ST PV for different locations is useful. A market survey assessing average price performance both 2013 2021 was conducted, showing factor of 3 cell decrease combined with 20% efficiency increase, while showed negligible variation. Winsun simulations were results plotted on world map. Despite variations due to local climate, production (ST/PV) increases at lower latitudes mainly (a) higher air temperature increasing but decreasing output; (b) solar radiation reducing zero having minor impact efficiency. The calculated several operating temperatures. For than 66°, flat plate 50 °C module ranges from 1.85 4.46, vacuum tube 3.05 4.76. This can support decision installing or combining factors such value, system complexity, installation cost.