Mr. EV

Solar & battery savings

Solar & battery installed by Heatable

£150 off solar £75 off a battery £50 off your Octopus bill referral

2026 1 Jan 2026 – 31 Aug 2026 Updated 31st August 2026
Total benefit
£1,930
Saved on bills
£1,375
Earned exporting
£555
Top solar day
72.0
kWh on 13 Jun 2026
Solar generated
8,064
kWh · 43% used at home
Battery discharged
3,192
kWh · £435 of the saving
Exported
4,589
kWh sold back to the grid
EV charging
£231
1,740 kWh · not counted as saving
Would have paid
£2,483
with no solar and no battery
Actually paid
£1,108
before export payments and standing charge
Household use
9,679
kWh · 33% not bought from the grid
Paid back
22%
£4,118 of £18,990 · 5.4 yrs to go
Heating
4,686
kWh · £599 of the bill
By month Jan → Aug
Benefit £1,930
Solar 8,064kWh
Used 9,679kWh
Battery 3,192kWh
Exported 4,589kWh

This tool was built with Claude

Every line of it — the Octopus and AlphaESS clients, the settlement model, this screen — was written in conversation with Anthropic's Claude. Here is what that cost.

Tokens
110.8million
across 364 requests · measured
Electricity
2.3kWh
estimated · 0.7–8.3
Carbon
294g CO₂e
estimated · 83–1,039
Fresh water
2.5litres
cooling only · 0.7–9.0

Roughly 3.3% of what this roof made on its best day.

Only the token count is measured. Anthropic publishes no per-token energy figures, so the rest is inferred from Google's first-party measurements of its own models and from published per-token estimates — two methods that disagree by about ninety times, which is why these are ranges and not numbers. The water figure covers datacentre cooling only, not the water used to generate the electricity, so read it as a floor. Model training is excluded: it is shared across everyone who ever uses the model and cannot be fairly attributed to one project.