Mr. EV

Solar & battery savings

Solar & battery installed by Heatable

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

All time 7 Apr 2025 – 31 Aug 2026 Updated 31st August 2026
Total benefit
£4,118
Saved on bills
£2,599
Earned exporting
£1,519
Top solar day
72.0
kWh on 13 Jun 2026
Solar generated
16,212
kWh · 32% used at home
Battery discharged
7,854
kWh · £1,020 of the saving
Exported
11,011
kWh sold back to the grid
EV charging
£464
3,552 kWh · not counted as saving
Would have paid
£4,925
with no solar and no battery
Actually paid
£2,326
before export payments and standing charge
Household use
19,458
kWh · 22% not bought from the grid
Paid back
22%
£4,118 of £18,990 · 5.4 yrs to go
Heating
8,345
kWh · £1,055 of the bill
By month Apr → Aug
Benefit £4,118
Solar 16,212kWh
Used 19,458kWh
Battery 7,854kWh
Exported 11,011kWh

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.