Earth Notes: On Website Technicals (2026-07)
Updated 2026-07-11.: Cadence
For the by-month grid CO2 calculations, I have moved the monthly intermediate/cache files from out/yearly to the more appropriate out/monthly, eg:
... Enphase-1h-202605.csv.gz FUELINST-1h-202605.csv.gz Enphase-join-FUELINST-1h-202605.csv.gz 16WW-elect-kgCO2-202605.txt Enphase-1h-202606.csv.gz FUELINST-1h-202606.csv.gz Enphase-join-FUELINST-1h-202606.csv.gz 16WW-elect-kgCO2-202606.txt ...
: Edge Cases Worked!
Elexon's API went down for scheduled maintenance this morning, so after a while (~2h) the diversion control code decided that grid intensity data was too stale and stopped diversion as fail-safe. Graceful success/failure in unusual circumstances #1!
The API came back (ahead of schedule) and diversion started again because even though the grid was not green (G), a large rise in grid intensity over the next ~2d was predicted (P), so the system went into "fill your boots" mode. Success in unusual circumstances #2!
2026-07-07T13:51Z MT 0 GI 85 IT 40 F FqP2TCN ES 3
: Export/Dump for Red Grid
In line with attempting to provide more (indirect) assist to the grid when most useful (though tiny, ~12W!) from the off-grid system, I have re-enabled 'E' dumping when the grid intensity is red (top quartile) alongside the cron-set grid-peak flag.
That GBGRIDPEAK.flag timing still looks good, around Z. Maybe it could start a little later.
#Ansible: 16WW: set /run/GBGRIDPEAK.flag in winter months 19 16 * 11-12,1-3 1-5 touch /run/GBGRIDPEAK.flag #Ansible: 16WW: clear /run/GBGRIDPEAK.flag 39 18 * * * rm -f /run/GBGRIDPEAK.flag
: red ahoy!
The 'E' took effect again for the first time quite soon, as the grid went 'red':
2026/07/07T16:30:06Z AL 754 B1 12674 B2 -1 P 18834 BV 12249 ST OK D E A1P 9543 B1T 31 UC 100 A1V 25538 2026/07/07T16:40:06Z AL 708 B1 12589 B2 -1 P 22296 BV 11240 ST OK D E A1P 8818 B1T 31 UC 100 A1V 25489 2026/07/07T16:50:06Z AL 508 B1 12549 B2 -1 P 22262 BV 12030 ST OK D E A1P 6402 B1T 31 UC 100 A1V 24421 ...
I have also tweaked to maybe better avoid sulphation by reducing dumping after failing to achieve a decent level of charge (VHIGH) for several days.
: gated on imports
I have gated 'E' behind there being significant imports, ie to operate only when the AC-coupled battery is unable to hold the line. That gets state back to 'e':
2026/07/08T20:20:06Z AL 0 B1 12491 B2 -1 P 15814 BV 12091 ST OK D e A1P 0 B1T 32 UC 100 A1V 12970
'E' could also operate when there are significant exports, but may then inflate spill to a grid already flooded, so we might as well preserve LA battery life.
I have added to 'e' to dump when high SoC and grid red intensity (may be exporting) to reduce grid emissions.
: Tweaking Solar Noon Dumping
The time at which the last parts of heat/DHW storage can be filled by diversion has moved forward a little more, after inspection of June's grid export graph, to Z. The aim is a flatter smoother summer export curve, while continuing to reduce exports when other grid-connected solar generation is likely around maximum.