Rolling 12 months 10 Nov 2025 – 9 Nov 2026 Updated 8th November 2026
Total benefit
£2,640
Saved on bills
£1,999
Earned exporting
£642
Top solar day
72.0
kWh on 13 Jun 2026
Solar generated
9,855
kWh · 46% used at home
Battery discharged
5,075
kWh · £764 of the saving
Exported
5,275
kWh sold back to the grid
EV charging
£192
2,618 kWh · not counted as saving
Would have paid
£3,776
with no solar and no battery
Actually paid
£1,777
before export payments and standing charge
Household use
14,760
kWh · 28% not bought from the grid
Paid back
24%
£4,536 of £18,990 · 5.5 yrs to go
Heating
6,963
kWh · £898 of the bill
By month Nov → Nov
Solar Used Battery Exported Benefit (£) Cash flow (£)
2,228 0 kWh £326 0 −£413

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.

By month Nov → Nov
Solar 9,855kWh Used 14,760kWh Battery 5,075kWh Exported 5,275kWh Benefit (£) £2,640 Cash flow (£) −£1,135
2,228 0 kWh £326 0 −£413
Nov Jan Mar May Jul Sep Nov