Doing a reading for my Renewable Heat Incentive has made me do a few calculations and see how the energy use in the house is going.

We don’t have a realistic winter season to look at yet (here are the calculations I made), as much of the time when the heat pump was on, we had it on full, drying out the house. I could only turn on the MVHR when the work in the house stopped, due to the dust, and so I always had at least one window open until we switched the MVHR on in April.

However we now have a realistic summer. I turned the heating off in the house in April/May (I forget the date) so the following heat calculation is just for hot water. The house has stayed quite happily at 20degrees since April despite having no heating on.

So over the summer period (131 days)

We used 991 units of electricity in total (paid 14 p per unit)

• 440 units of electricity for heating (47p per day)
• 551 units for the rest of the household (58p per day)

We generated 1397 Units in solar electricity (we were paid 12.8p for – £1.36 per day)

I really cannot work out how the energy we use when the sun is shining is calculated though. Does this go on the electricity meter….

Who knows. Who cares.