Is there a device to measure how much electric is being used by a central air conditioner?

Yes, there are devices called energy monitors or power meters that can measure the electricity usage of a central air conditioner. These devices can be installed on the electrical panel or connected directly to the AC unit to provide real-time data on energy consumption. Some smart thermostats also offer monitoring features that track energy usage over time. This information can help homeowners understand their energy costs and optimize their AC usage for efficiency.