core/homeassistant/components/utility_meter/icons.json

{
  "entity": {
    "sensor": {
      "utility_meter": {
        "default": "mdi:counter"
      }
    },
    "select": {
      "tariff": {
        "default": "mdi:clock-outline"
      }
    }
  },
  "services": {
    "reset": "mdi:numeric-0-box-outline",
    "calibrate": "mdi:auto-fix"
  }
}