This thesis considers three design configurations of air source heat pumps and building-integrated photovoltaic (BIPV) systems in a solar house concerning energy efficiency and energy flexibility in interacting with a smart grid. BIPV/Thermal (BIPV/T) provides electricity generation and reduces the electricity consumption when pre-heating air for a heating, ventilation, and air conditioning (HVAC) system such as a heat pump. A heat pump’s coefficient of performance (COP) and capacity decrease at colder temperatures. Therefore, increasing the inlet temperature can significantly increase the capacity or enable a heat pump to operate when the outdoor air is below the cut-off temperature. A higher COP enables an efficient heat transfer and storage when heat is available; this provides flexibility to the system. Energy flexibility is an important factor to consider as providing flexibility to the grid helps alleviate its demand and stress during critical periods. In addition to the grid’s need, the utility often provides incentives for consumers to reduce electricity consumption during critical periods. Adopting advanced controls that can provide flexibility is beneficial to help reduce overall electricity consumption and energy cost.
A comprehensive literature review of various BIPV systems and their applications demonstrated a gap in the current research to investigate the possibility of utilizing solar gain (from inside a solarium or greenhouse) to pre-heating air for a heat pump. Furthermore, the use of semi-transparent photovoltaic (STPV) windows with a heat pump have not been explored. Thus, a new configuration is proposed utilizing the solar heated air in an attached solarium as a source for the air side of an air-source heat pump water heater (HPWH) with integrated water thermal storage and a 5kW semi-transparent photovoltaic façade. This configuration is compared with two other cases: a reference case consists of a 5kW BIPV system on the roof with a separate HPWH and a more novel option of a 5kW BIPV/T roof system. The heated air from the BIPV/T system is ducted to the air source of the HPWH, which also contains integrated thermal storage (the hot water).  The three cases are modelled with an explicit finite difference thermal network model, and energy performance is determined and compared over a typical heating season in Montreal. 
Another important gap in the research found from the literature review is maximizing the flexibility of BIPV/T and heat pump systems. Thus, the energy flexibility of the BIPV/T configurations listed previously is compared for different scenarios, such as heating the thermal water storage during the daytime (e.g., using the solar heat in the novel options) and using it for space heating during the time that the grid is under stress (and may have price incentives). 
A full-scale experimental set-up modelling the passive solar case was completed to demonstrate this novel system configuration and to partially verify the developed model using the Future Buildings Laboratory at Concordia University. The real-time data collected from the experiment is analyzed and utilized to verify each component within the system. Results show that the proposed case utilizing the solarium air as the inlet of the heat pump had over 80% reduction in annual electricity consumption relative to the reference. In comparison, the BIPV/T configuration had around a 5% reduction compared to the reference case. The proposed configuration improves system performance significantly compared to the reference and ducted BIPV/T systems. The tank volume and solarium size had the highest impact on the system's energy flexibility. Optimal thermal storage size was between 300 – 600 L for a house with a floor area of 116 m2. The experimental results confirmed the increased energy savings from the passive solar configuration operation. The temperature in the test rooms reached over 20 °C on a cold sunny day from passive solar gains. The simulation models had a similar performance to the experimental data which also demonstrated the significant energy flexibility potential of the configuration tested.