Photovoltaic thermal water Systems - modelling and design considerations for residential applications in different climates and demand conditions

This Thesis presents the work of the author on PVT-water modules and systems as retrofits for existing households. Two computer models were developed in order to analyse and characterise PVT systems: one for steady state conditions, used for annual yield simulations, and a full transient model, used for the detailed analysis of PVT modules performance and behaviour. Also, a PVT module was designed based on commercially available parts and materials. The design was built as part of the experimental setup that was used to fine tune and verify the accuracy of the computer models developed. Results show that both models offer high accuracy when compared to experimental data and a better agreement with the data than commercial software packages. Simulations for domestic PVT-water systems were carried out for different climates and load profiles, characterised by the demand found for the average households in two countries: a developed economy (Australia), and an emerging economy (Chile). The results show that not only the performance and type of PVT module must be considered in the design of the system, but also the demand profiles and the other system components. This differs from the PV market where a “one design fits all” approach is possible. It is determined that a systemic approach should be used when characterizing PVT-modules because of the very nature of the technology, and that different solutions should be applied for a same system under different conditions. When all these effects are taken into account, it is concluded that PVT-water systems are a viable solution for the growing energy demand in the residential sector