Performance modeling of a building-integrated photovoltaic/thermal air heating collector

A computer simulation model of a Building-Integrated Photovoltaic/Thermal (BIPV/T) collector is examined in this thesis. The system under investigation has been developed by PVT Solar under a research and development contract from the National Renewable Energy Laboratory (NREL). The collector design utilizes unglazed PV/T collectors preheating air for glazed air heating modules. For each collector type, an unsteady-state model has been created from analytical expressions of surface temperatures, the rate of extraction of useful thermal energy and the outlet air temperature. Measured data is used to calibrate the two heat transfer models implemented in Transient System Simulations (TRNSYS).;The calibrated model is then used to study the annual performance of the BIPV/T system for residential applications in seven climate zones of the United States of America. The performance of the BIPV/T array is characterized by the amount of net electrical energy and useful thermal energy produced. The useful thermal energy is defined to be the amount of auxiliary energy offset by the BIPV/T system for water heating and space conditioning.;The system is simulated with a fixed collector area equivalent to 4kW PV array. In each of the seven climate zones the ratio of PV to glazed collector modules is varied to determine at what arrangement the maximum amount of site energy, source energy and energy cost is offset and what arrangement offsets approximately the same amount of source energy as a 4kW roof mounted PV array. The results found the maximum amount of energy is typically offset by an 87.5%PV or 100%PV collector ratio arrangement. However, the 4kW roof mounted PV breakeven point is often realized using only 62.5%PV to 75.0%PV. These breakeven points are used to determine how much money could be spent on the necessary additional thermal components of the BIPV/T system.;Secondary system performance analyses are performed to determine what aspects of the system should be studied in future work to improve performance of the BIPV/T system. The analysis on the array size shows this is clearly an important parameter of the system and is greatly dependent on the climate and building loads. Another analysis on the use of setback heating set points also showed the importance for improved control logic, for both the collector system and the building. Finally, simulation sensitivity analyses are performed to determine what parameters within the collector models, that have an associated uncertainty in determining, are most important to study in future work.