**5. Conclusions**

The performance of a solar PVT consists of PVT collector and storage tank is evaluated for 85 locations across large cities. The optimal tilt angle of the PVT collector, load demand, and electricity prices are chosen appropriately for each simulated location. The results show that the major parameter influencing the PVT performance is GHI, and results derived a strong linear correlation between collector output and GHI. The other factor influencing energetic performance is ambient temperature, source, and load water temperatures. The energetic utilization ratio is dependent on total thermal demand and specific volume ratio (v/a ratio) as it can have a major influence on the fluid temperature in the storage tank and, thus, collector total production. The electrical production by PVT collector is higher in high ambient temperature locations. The highest and lowest energy utilization ratio of the collector is recorded in Reykjavik, Iceland (63%), and Medina, Saudi Arabia (54%), respectively. The highest and lowest exergetic efficiency of the collector has been recorded in Reykjavik, Iceland (23%), and Medina, Saudi Arabia (17%), respectively. Most importantly, the results show that the higher energetic output does not guarantee high economic feasibility. There are several factors such as electricity price, interest rate, and selection of financial model which can highly affect the economic feasibility of PVT collector. The average NPV per unit collector area of 85 geographical cities for financial model 1 and financial model 2 is 1886 and 2221 EUR, respectively. The NPV and payback period analysis of the PVT system has shown positive results for the cities, which have high collector production and high electricity grid price reflecting high energy savings. However, the financing model 1 is highly recommended for the locations with high interest rates and financial model 2 is beneficial for the locations with less interest rates. This paper offers potential insights into the promotion of the PVT market in different regions.

**Author Contributions:** S.R.P. worked on simulation, analysis, and writing. X.Z. contributed to supervision, concept development, structuring, and writing. P.K.S. contributed to simulation, analysis, and writing. A.d.A. dedicated efforts to simulation and analysis. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received funding from the Germany–Sweden joint project: 'Product and process development for the preparing and realization of complete buildings of various types of use using energy efficient, partially energy independent lightweight construction solutions, ENSECO'.

**Acknowledgments:** The authors acknowledge the useful gains from the IEA SHC Task 60, and the open access support from Dalarna University, Sweden.

**Conflicts of Interest:** The authors declare no conflict of interest.
