Governments in many countries implement suboptimal policy measures to increase the uptake of solar PV systems, as they are rarely designed from a system perspective. Drawing from a rich empirical dataset of consumer preferences for clean energy technologies, we examine the impacts of different policy incentives on household choices to adopt solar PV with and without batteries using an agent-based model. We find that policy design can have significant influence on the uptake of solar PV systems, storage options, and the overall financial net benefits for households. Thus, policy instrument design targeting optimised systems, rather than solar PV alone, delivers welfare benefits.