Australia’s energy system is increasingly relying on households. With more than four million homes now sporting rooftop solar, and batteries, EVs and smart appliances rapidly growing, consumer energy resources are becoming central to how the grid operates. But there’s a problem emerging beneath this transformation - many of these devices still can’t properly communicate with each other. Dani Alexander from the UNSW Energy Institute explains the importance of interoperability, the technical standards and systems that allow solar, batteries, EVs, retailers and networks to ‘talk’ to each other, and how a lack of interoperability could lock consumers into closed ecosystems and reduce consumer choice.