Home energy monitoring services like Neurio have an API to poll usage data for circuits in the home. When combined with sub-metering, it's possible to pull the kWh consumed by the charging circuit, allowing for even better efficiency calculations. Can you investigate adding support for services like this?
Neurio API: https://api.neur.io/docs/
Sense IFTTT: https://ifttt.com/sense_energy_monitor
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