The technical and financial influences that shape customer investment in behind-the-meter PV and battery systems, provide the means to forecast and quantify customer energy transitions. By utilising techno-economic scenario analysis, this research assists policymakers to understand the impacts of their decisions on future energy market relationships between the customer and utilities. Two case studies are presented, firstly to evaluate the influence of annual increases in usage charges, and secondly the level of feed-in tariff compensation on customer PV and battery investment over a 15-year forecast period located in Perth, Australia. The findings indicate that even without annual increases in usage charges, the falling installation costs of PV and battery technologies will make customer PV-battery systems financially viable within the 15-year forecast period. Additionally, the removal of the feed-in tariff leads to greater reductions in eventual grid consumption. By the end of the forecast period, customer PV-battery systems with the highest financial performance are able to reduce grid consumption above 90% resulting in significant energy resources being transferred out of the energy market. This necessitates the market integration of customer energy resources and provides an opportunity to leverage a combination of customer and utility energy resources for the renewable energy transition.