Charging Stats

Charging Stats

The Stats tab provides you with a view of your EV charging history, which can be viewed over daily, monthly or yearly periods.

Bar graph data

  • Total charged: reports the total charging energy from all sources for the period being viewed.
  • Self-Powered: reports the percentage of total charging energy which came from your solar or home battery for the period being viewed.
  • The bar graph shows hourly increments in the day view, daily increments in the month view and monthly increments in the year view.
  • Solar: is energy from your rooftop solar PV for EV charging.
  • Grid: is energy imported from the grid for EV charging.
  • Battery (if present): is the energy supplied by your home battery.
  • Other: represents a combination of a) charging away from your home location such as DC fast charging, b) energy used by the car that is not for charging (e.g. heating and cooling whilst connected to the charger) and c) in a small number of cases where we can’t determine the energy source such as when your solar data feed is interrupted.

Energy source summary

  • Each view provides you with a breakdown of charging based on the energy source, Solar, Battery, Grid and Other. Energy (kWh) totals and percentages are shown for each source.

Navigating the stats screen

  • Switch between Daily, Monthly and Yearly views using the slider at the top of the screen.
  • Scroll through the previous days, months and years by swiping left or right anywhere on the graph, or using the < and > arrows above the bar graph.
  • Toggle on/off energy source data sets by tapping their names in the graph legend.

Grid usage when charging from solar

  • It’s normal to see small amounts of energy used from the grid or home battery each day during solar charging periods. This is a result of home solar production and energy consumption varying almost instantaneously (millisecond level) whilst Charge HQ has to wait for updated solar data before it can adjust the charging power.
  • There will be a greater percentage of grid usage where the amount of solar is lower or more variable (e.g. cloudy days).  Charge HQ is designed to continue charging from the grid for short periods when solar production falls to avoid excessive start stop behaviour of your charger. Read more about avoiding contactor wear.
  • Solar data sources with slower solar data feeds will also see more grid usage.
  • On days with a moderate volume of charging, less than 5% grid consumption should be considered good and less than 1% considered excellent.
  • On day with low volumes of EV charging or highly variable excess solar production you may see 20%+ consumption from the grid.
  • Users with larger solar systems (e.g. >10kW), particularly those where output excess the maximum speed of the charger, will often see lower levels of grid consumption than users with smaller solar systems (e.g. <5 kW).
  • Setting a small solar tracking margin (of say 0.5 kW) may in some cases reduce grid consumption whilst solar tracking is active but at the expense of greater levels of solar being exported whilst charging.

Notes

  • The graphs only show energy consumption for EV charging and exclude any other consumption in the home.
  • The stats are updated once every 15 minutes.