Smart meters don’t need the internet to communicate. Instead, they work by using two wireless networks: the HAN (home area network) and WAN (wide area network). Which network they use depends on what they’re communicating with.
Your HAN is a secure network contained within your home that allows digital devices to communicate with each other. This network is used to allow your smart gas and electricity meters to communicate with each other, as well as with your in-home display.
When smart meters need to communicate with an energy provider, they use WAN. This secure network is similar to the one mobile phones use to send and receive data. It’s run by the Data Communications Company and overseen by the energy regulator Ofgem. This means it must comply with strict regulations to ensure smart meter data is kept private and secure.