Practice theories have generated interest in sustainability transitions research as a means to study shared expectations, conventions and routines that maintain unsustainable consumption within the dominant regime. However, collective action to change practices, which is crucial for innovation, is seldom examined in practice theory research. This article applies practice theories to conceptualize the nature of collective action in shaping energy practices, using insights from a literature review on residential photovoltaic (PV) production by German citizens. We demonstrate the significance of latent networks, which refer to individuals involved in similar parallel practices, in promoting the adoption of solar power in homes. Our results show that both multi-actor and latent networks contributed to mainstreaming residential solar PV practices. Multi-actor networks encompassed households and various service providers, each integrated within larger latent networks.