Abstract
This paper presents numerical and experimental analyses aimed at evaluating the technical and economic feasibility of photovoltaic/thermal (PVT) collectors. An experimental setup was purposely designed and constructed in order to compare the electrical performance of a PVT solar field with the one achieved by an identical solar field consisting of conventional photovoltaic (PV) panels. The experimental analysis also aims at evaluating the potential advantages of PVT vs. PV in terms of enhancement of electrical efficiency and thermal energy production. The installed experimental set-up includes four flat polycrystalline silicon PV panels and four flat unglazed polycrystalline silicon PVT collectors. The total electrical power and area of the solar field are 2 kWe and 13 m2, respectively. The experimental set-up is currently installed at the company AV Project Ltd., located in Avellino (Italy). This study also analyzes the system from a numerical point of view, including a thermo-economic dynamic simulation model for the design and the assessment of energy performance and economic profitability of the solar systems consisting of glazed PVT and PV collectors. The experimental setup was modelled and partly simulated in TRNSYS environment. The simulation model was useful to analyze efficiencies and temperatures reached by such solar technologies, by taking into account the reference technology of PVTs (consisting of glazed collectors) as well as to compare the numerical data obtained by dynamic simulations with the gathered experimental results for the PV technology. The numerical analysis shows that the PVT global efficiency is about 26%. Conversely, from the experimental point of view, the average thermal efficiency of PVT collectors is around 13% and the electrical efficiencies of both technologies are almost coincident and equal to 15%.
Highlights
In the last years particular attention has been paid to the development of economically viable solar thermal and electrical systems, with the twofold aim at improving power density and reducing system capital costs
The electrical energy produced by the PV panels, Eel PV, equal to 1778 kWh/year, is greater than that, Eel PVT, produced by the PVT collectors, which provide thermal energy used for DHW purposes
The economic savings due to the electricity production by PV panels is about 296 €/year, whereas the economic saving due to the electricity and thermal energy production by PVT collectors is about 650 €/year (Table 6)
Summary
In the last years particular attention has been paid to the development of economically viable solar thermal and electrical systems, with the twofold aim at improving power density and reducing system capital costs. Among European Union countries, one of the goals of the established energy policies is to achieve a widespread adoption of small SC and PV systems, in order to enhance the utilization of renewable energy sources [1,2]. In this framework, photovoltaic/thermal (PVT) collectors are promising due to their combination of conventional PV and SC collectors in a single component [3,4]. PVT collectors are Energies 2016, 9, 497; doi:10.3390/en9070497 www.mdpi.com/journal/energies
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
