Commercially available STPV windows can convert between 5% and 20% of the incident solar radiation into electricity, while the portion of solar energy that is converted into heat (roughly 30% to 70%, depending on the optical and thermal properties and PV technology used) contributes to the increase in temperature of the PV cells.
In a STPV window, the SHGC is also influenced by the electrical conversion efficiency of the STPV glass; the higher the efficiency, the lower the SHGC--more absorbed solar energy is transformed into electricity rather than into heat.
Considering the current advancements in the window industry, such as electrochromic windows, STPV windows, and windows incorporating angular selective coatings (Fernandes et al.
2014a, 2014b) proposed a methodology for the optical electrical and thermal characterization of STPV windows using an outdoor calorimeter.
2012) developed an outdoor calorimeter to determine the electrical and thermal output of STPV thermal windows.
On the other hand, there are efforts to develop an international standard (ISO/DIS 19467) for the determination of SHGCs of conventional and advanced fenestration systems such as STPV windows using a solar simulator (ISO 2015).
It was noticed that STPV had excellent long term elastic recovery properties, based on compression set, that increased by only 5%.
It is observed that the properties of the STPV were better balanced than those of the CTPVs, even though the STPV had slightly lower elongation at break.
In the STPV, the Tg of the soft segment was -52[degrees]C and the glass transition peak for polystyrene broadened at around 118[degrees]C.
Figure 9(b) shows that the STPV also has nano scale domains approximately 30 nm in size.
After dynamic vulcanization, the morphology on a micro scale for a STPV is similar to that of a CTPV.
The STPV was shown to have excellent stable long-term compression set and improved hot oil resistance at 125[degrees]C compared to conventional PP/EPDM TPVs.