Some Smart Meter Data

Now that our smart meter communications hub is communicating, the last 30 days of meter data has been downloaded and you can see the effect of our solar panels and battery.


Half of September cost us approximately £11


and October to date has cost us £20


Our heating and hot water is provided by our Air Source Heat Pump. These consumption/generation graphs come from the Mitsubishi MELCloud app. I know our energy use is low but I do doubt the COP calculations in these screenshots. A COP over a week of 7.8 seems too good to be true.


Nearly all the electricity we've used in September and October has come from our solar panels, often being stored in our batteries. Todate, we've been running our system in "Self Powered" mode minimising the need to draw power from the grid. Solar power is used, in this order, to:

  • power immediate demand
  • recharge the battery
  • export to the grid
and we've only imported from the grid when the battery is discharged. In September 


and October to date


we've imported 24kWh and 43.4kWh.

Here's a graph from Home Assistant showing yesterday (16th Oct) and today (17th Oct) to date.


Yesterday was a pretty good solar generation day. You can see the heating come on at about 7am and being powered by the battery - turquoise line. Then as the solar comes in (yellow line) the battery load drops and you can see the house load (blue line). As the solar improves the battery charges (discharge goes negative) and then we have so much solar that we can power the heating, recharge the battery at maximum charge rate and export to the grid. Not bad for mid-October. Once the battery is fully charged and the house warmed up, the solar generation has to be curtailed because we can currently only export at 3kW to the grid. Yes, that's lower than a G98 allowance.

Today was go such a good solar day. The battery did not go below 43% charge level and has since fully charged this afternoon so we should not draw any power from the grid today.

It will be interesting to see how the winter goes and what happens once we get our smart tariffs sorted.


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