Photovoltaic (PV) generation is emerging as a significant technology in the global energy transition. However, while rapid urbanisation is driving increasing housing density, PV uptake in multi-occupancy housing has been limited by comparison with stand-alone housing in many jurisdictions, including in Australia, despite its world-leading 22% residential PV penetration. This thesis presents a multidisciplinary analysis of the opportunities and challenges for, and costs and benefits of, rooftop PV deployment on Australian apartment buildings. A novel geospatial analysis was used to assess the opportunity for solar on Australian apartment rooftops. Statistical and cluster-based analysis was used to characterise individual and aggregated apartment load profiles. Reviews of the academic literature and Australian regulatory arrangements, together with a series of stakeholder interviews, were undertaken to identify potential implementation arrangements for, and barriers to, deployment of apartment PV. Modelling of PV generation, energy and financial flows was used to compare outcomes for diverse buildings under different PV configurations. The size and diversity of the dataset and the variety of arrangements modelled represents a significant contribution to the literature. The thesis identifies potential PV capacity of 2.9GW – 4.0GW on Australian apartment buildings and describes significant differences between load profiles of apartments and houses. Applying PV generation to aggregated building loads is shown to increase self-sufficiency and PV self-consumption, compared to separate systems supplying common property or individual apartments, and can sometimes generate financial benefits for customers. While embedded networks can enable access to beneficial retail arrangements, behind the meter solutions may reduce regulatory complexity and cost. Optimum solutions depend on building characteristics and financial settings. Adding battery energy storage systems (BESS) can further increase self-sufficiency and decrease peak demand but the economic case is not compelling with current capital costs. Barriers including building stock diversity, demographic factors and knowledge issues, as well as specific Australian regulatory arrangements concerning governance of apartment buildings, regulation of the energy market, and electricity tariff policies, impact on the options available to apartment residents to act co-operatively in accessing renewable energy. This research identifies possible emerging business models and policy approaches to support increased apartment PV deployment.