See Energy production in the Energy dashboard · Issue #8 · fsaris/home-assistant-zonneplan-one · GitHub this value is in watt that’s also visible in the Zonneplan app that way. But you can add a additional sensor to your configuration that calculates a energy kWh value based on the production W value.
- platform: integration
source: sensor.zonneplan_p1_electricity_production
name: electricity_production
unit: kWh
unit_prefix: k
round: 2
See also Integration - Riemann sum integral - Home Assistant