Smart meters and submeters

Overview of the status and impact of the innovation

Innovation 2


Smart meters measure and record electricity usage (typically in real time), communicate the information to consumers and grid operators, and report back to electricity suppliers for monitoring and billing. By supporting two-way communication and bidirectional flows of information, smart meters have become a significant component of today’s power networks and utilities. In addition, “submeters” have emerged to monitor the energy demand of particular appliances. They make it possible to bill EV load on a different rate schedule than that of the rest of the household load.


Smart meters are essential for allowing EV charging at the best times for both the power system and drivers, bringing more value to both. Meanwhile, smart submeters for EV chargers remove a barrier to V2X adoption (Box 3.11).

BOX 3.11 Avoiding the need for new EV submeters in California

Utilities in California have for some time offered special electricity prices for EV charging, but few customers were taking advantage of these prices because of a requirement that they install a separate submeter to measure EV charging. In 2022, regulators in California approved a protocol that enables installed smart meters to measure and bill EV charging separate from other electricity uses, thus accelerating vehicle–grid integration.

Source: (State of California, 2022).

BOX 3.12 Submeters for the EV charging platform of State Grid, the electric utility in China

On State Grid’s orderly charging platform for EVs, submeters are integrated into the charging pile as core control units; the charging pile receives the orderly charge and discharge instructions from the energy controllers upstream and connects the orderly charging piles downlink to control the charging of electric vehicles. In addition, submeters also support information exchange with users’ mobile phones. The main idea is to implement dynamic tariffs, which offer different prices for electricity at different times of the day and enable electricity users to choose power consumption periods and preferred charging modes. This strategy can effectively improve users’ charging service experience, including enjoying more favourable charging prices, higher charging efficiency and many other benefits.

Source: (Ting et al., 2021).