August 2025 updates
August Electric:
I managed to maintain a 9.01% Peak/Off-Peak ratio, which down on last month’s 4.88%.
There were a quite a few days that were overcast, and on the rest I managed to have only minimal peak usage.
Electricity costs for the month of August: £107.10 for 2025, £123.22 for 2024 and £462.29 for 2023 – better than last year, and still way better than the year before.
Electricity demand for the month of August: 1752kWh for 2025, 1882kWh for 2024 and 1410kWh for 2023.
The saving for this year was around £16.00 less for 130kWH less usage.
The off-peak/peak/SC values for August were £0.07/0.24393/0.488 for 2024 vs £0.07/£0.2896/0.4542 for 2025, which are the same as last month.
This can also be seen in the month on month usage vs cost graphs:
August Solar:
Actual production for August far exceeded the forecast for every day, often by way more than double.
The various arrays produced the following levels of energy: Garage 287.65kWh, Office 224.35kWh, East 192.59kWh, West 225.13kWh for a total of 929.72kWh starting to tail off now that we have passed peak summer
A reasonable month for solar production, I also managed to export 226.36kWh for a total saving of £33.95.
The import costs of £107.10 less the export savings of £33.95 means my net cost for August was £73.15 for 1752kWh of demand making my average rate £.0419/kWh.
August Gas:
Gas costs for the month of August: £28.97 for 2025, £23.73 for 2024 and £-815.29 for 2023 (strange refund situation).
Gas usage for the month of July: 427kWh for 2025, 316kWh for 2024 and -1169kWh for 2023 (again weird numbers).
£5.00 more than last year, 30% more gas consumed and on the Octopus Gas Tracker tariff vs the Octopus Standard Gas Tariff, so similar to last month.
Gas prices remained about the same this month, I would have paid a lot more had I still been on the Octopus Standard Tariff, which was £0.0699 per kWh for August £40.03 ((427 * 0.0699) + 10.18sc) or an additional £12.06 for the month.
The heating was off for the entire month, so gas was only used for heating the hot water.
Again all visible in the usage vs cost graphs.
There were a number of ‘free electricity sessions this month that had some quite wildly different savings
05/08 I used no additional electricity, so saved nothing – I think I learned about this one too late to do anything about it
09/08 I used an additional 8.12kWh and saved £0.57 (8.12 * 0.07/kWh) – this was an ‘off-peak’ saving because the car was plugged in and Octopus gave me a charging session that overlapped with the ‘free electricity’.
31/08 I used an additional 13.05kWh and saved £3.03 (13.05 * 0.2896/kWh) – much better, as this was a ‘peak rate’ saving
For both of the later sessions I also discharged the batteries for an hour or so beforehand so I would be able to charge them to a decent level during the ‘free’ periods.