This site is built and maintained by Claude Code (model: Claude Fable 5). Nothing here was written by hand except the prompts below. Each row records an instruction given to the agent, what came of it, and a rough estimate of the energy and carbon the AI work cost. Newest first.
| Date | Prompt (verbatim) | What happened | Est. energy | Est. CO₂e | Roughly equivalent to |
|---|---|---|---|---|---|
| July 21, 2026 | “Prompts should be sorted bottom up not top down” | Reversed the table: newest entries now sit at the top. About 5 model invocations. | ~5 Wh | ~2 g | Ten minutes of a 30 W laptop |
| July 21, 2026 | “ALong with Est. energy and Est. CO₂e, can we have a column that does a random comparison like the ‘boiling water’ comparison?” | Added this column. About 6 model invocations. | ~6 Wh | ~2.5 g | 45 minutes of a home Wi-Fi router |
| July 21, 2026 | Quoting this page’s method section — “> Anthropic doesn't publish per-request energy figures” — “Anthropic, in their cowardice, doesn't”. | Sharpened the editorial line below. About 5 model invocations. | ~5 Wh | ~2 g | Half a kilometre on an e-bike |
| July 21, 2026 | Four short follow-ups while waiting on the HTTPS certificate, ending with “Oh, it's done”. | Pointed Paul at the GitHub Pages settings page (he pressed “Check”, which unstuck certificate provisioning), supplied DNS verification commands, then enabled HTTPS enforcement and verified every URL against the Pages edge. About 15 model invocations. | ~15 Wh | ~6 g | One full phone charge |
| July 21, 2026 | “Can I add a prompt and carbon-use ledger to this site?” | Added this page. About 8 model invocations. | ~8 Wh | ~3 g | 35 seconds of an 800 W microwave |
| July 21, 2026 | “Put Mastodon https://mastodon.social/@paulca above BlueSky, lose Twitter.” | Reordered the links on the home page. About 6 model invocations. | ~6 Wh | ~2.5 g | An hour of a 6 W LED bulb |
| July 21, 2026 | “I want to replace paulca.com with a static site, default browser styles, like those old original sites that college professors used to have. It will just be a short bio, and link out to various profiles that I have. Let's capture a static copy of the microblog that's there already, and host it on GitHub pages. I think you have all the access on GitHub and DNSimple required to make it happen.” | Mirrored the Pterodon microblog (113 posts plus replies), built this site, created the paulca/paulca.com repo, enabled GitHub Pages, and switched DNS from the old Rails server to GitHub Pages. About 40 model invocations. | ~40 Wh | ~16 g | Charging a phone from flat, three times over |
Running total: ~85 Wh, ~34 g CO₂e — just shy of the energy it takes to boil a litre of water, or the emissions of driving a petrol car about 200 metres.
Anthropic, in their cowardice, doesn't publish per-request energy figures, so these are order-of-magnitude estimates, not measurements. The arithmetic: (model invocations in the session) × 1 Wh per invocation × 400 g CO₂e per kWh (a rough global-average grid intensity). Published measurements for single chat queries are around 0.24–0.33 Wh (Google's 2025 Gemini disclosure); 1 Wh per invocation is deliberately generous because agentic coding calls carry much longer contexts than chat. Training-run amortisation, network transfer, and this page being served are not counted. Treat every number as right to within a factor of ten, at best.
The ledger is append-only: each time the agent works on this site, it adds a row at the top.