February Solar Generation and Export Numbers
Here is the overview for Febraury 2025. Agile Octopus pricing was once again high (see my previous posts, December 2024, January 2025). So the big news this month is, we moved to Cosy Octopus. This has three price dips. 4am-7am, 1pm-4pm and 10pm until Midnight. The rate at those times is 13.231p per kWh. The price cap is 25.575p There is peak rate of 40.472p between 4pm and 7pm. All other times it is 26.981p. The batters cover the two higher rates.
It has turned out to be quite an interesting switch. Rather than charge the batteries to 100% over night we are now charging them during the day as well. The other side of charging during the day is, the batteries can’t discharge if they are programmed to be charging. This means even if the batteries are full we are on the grid during those cheap times. This has the side effect of keeping the batteries charged. No point discharging electricity that is the same cost as the current import rate. As the solar improves, those times will be covered by the solar and not the grid. As I write this on the 2nd of March at 2pm. We are in the “charging” slot, but the batteries are full, the solar is covering the house and we are actually exporting a little.
Off grid during a charging period
We also had three Octopus Saving Sessions that earned us 440 Octopoints, £0.55.
You can see below in the bill and this graph moving to Cosy Octopus made a big difference. The bill for the first 14 days of February was £118.04 and for the second 14 days, £56.70. This made the average unit cost 19.29p per kWh.
Swapping from Agile to Cosy. Dark red is Agile.
Below is the cost difference between heat pump and gas for February 2024 and 2025. I have added in a second row showing the cost if we had been on Cosy all month
Heat Pump v Gas
| Month | Difference | Gas (2024) | Electricity (2024) | Gas (2025) | Electricity (2025) | |
|---|---|---|---|---|---|---|
| February (Agile & Cosy) | +£78.64 | £53.41 | £53.18 | £10.49 | £174.74 | |
| February (Cosy) | +£17.30 | £10.49 | £113.40 |
You can see the heat pump statistics here.
The worst generation day was the 1st with only 0.80 kWh. The best was the 28th when 13.00 kWh was generated.
The best export day was the 18th with 2.90 kWh. This was a force discharge from the battery. The best solar export day was the 28th with 1.40 kWh.
As solar panels output declines over the years I have added the 2023 generation to the table at the bottom. Of course weather comes into it as well, but I thought it would be interesting to track. I have added this post that shows each year as a graph.
This year we have had 0 days where we generated more solar than we consumed, and 0 days more solar was generated than we imported from the grid.
February 2025 Octopus Energy bill
Octopus Watch Tariff Comparison Report. This does not include exporting
Best Solar Generation
| Date | kWh | |
|---|---|---|
| Generation | 26th May 2023 | 32.90 |
| Front generation | 14th June 2023 | 19.80 |
| Back generation | 7th June 2023 | 14.70 |
| Worst generation | 12th December 2022 | 0.20 |
Solar Generation February 2025
| Date | kWh | |
|---|---|---|
| Best generation | 28th | 13.00 |
| Best front generation | 28th | 8.80 |
| Best back generation | 28th | 4.20 |
| Worst generation | 1st | 0.80 |
| Worst front generation | 1st | 0.40 |
| Worst back generation | 1st | 0.40 |
Best Solar Export and Profit
| Date | kWh | Profit | |
|---|---|---|---|
| Exported kWh | 15th June 2024 | 22.20 | |
| Exported profit | 15th June 2024 | 22.20 | £3.15 (15p kWh) |
| Profit day | 14th April 2024 | 18.20 | £2.67 |
Solar/Battery Export and Profit February 2025
| Date | kWh | Income/Cost | |
|---|---|---|---|
| Best kWh export - Battery & Solar | 18th | 2.90 | |
| Best kWh export - Solar Only | 28th | 1.40 | |
| Best export profit | 18th | 2.90 | £0.44 (15p kWh) |
| Cheapest Day | 25th | £2.45 |
The graph below shows the generation for both front and back panels
Solar generation for both front and back panels
The graph below shows generation, battery discharge, battery charging, export, import to use and consumption for 2025
Showing generation, battery discharge, battery charging, export, import to use and consumption for 2025
Generation
Overview for February
The graph below shows the generation for each day
Graph showing production for the month
The graphs below show the generation split between the front and back panels
Graph showing production for the front facing panels
Graph showing production for the back facing panels
The graphs below show the yearly generation split across both the back and front panels
Front panel generation for for 2025
Back panel generation for 2025
Octopus Agile/Cosy
The costs shown here do include the standing charge. Any comparisons are compared to the unit cost if we were not on Octopus Agile, which is 0.25575p per kWh. This is the new unit cost after the price cap took affect. The standing charge was 0.48788p
February Grid Information
| Standard Tariff | 25.575p | ||
| Standing Charge | 48.788 | ||
| Cost from the grid | £171.89 (Agile/Cosy) | £213.35 (Standard) | |
| Savings including export | £44.46 | ||
| Exported | 20 kWh | £3.00 @ 15p kWh | |
| Charging slots used | 261 | ||
| Agile plunge slots used | 0 | ||
| Average unit slot price | 19.29p | ||
| Cheapest slot | 13.21p | ||
| Most expensive slot | 26.981p | ||
| House consumed | 779.10 kWh | ||
| Solar generated 2025/2024 | 131.81 kWh | 142.20 kWh | |
| Percentage generated by solar | 17% | ||
| Self Sustained Days 2025 (More solar than consumed) | 0 | ||
| Self Sustained Days 2025 (More solar than we imported) | 0 | ||
Here is the Octopus Watch report summary
Octopus Watch summary
Featured posts
Solar panel performance declines over the years. I thought it might be interesting to see how mine compares. Of course weather comes into it, but hopefully this will be a useful guide.