Earth Notes: Saving Electricity (2025)
Updated 2025-03-02.Meter readings at home #defossilisation #fossilFree
Meter readings and analysis of our electricity and gas carbon footprint at home in 2025.
2025
See the daily PV generation logs for 2025 as .csv and .png chart.
The gas meter has gone: we are electricity only at 16WW for . 2025-02: Trendline
| 2025 | Electricity | |||
|---|---|---|---|---|
| Month | Consumed kWh (/d) | Generated -kWh (/d) | Period | Notes |
| 2025-01 | 425 (13.7/d) | -52 (-1.7/d) | 20251231T18:02Z to 20250131T18:00Z (31d) | Meter readings: electricity generation 51.7kWh, export 0.5kWh, import 374.0kWh (thus net consumption (I+G-E) 425.2kWh, self consumption ((N-I)/N) 12%). The Ecotricity bill for this month was lower than last January's even though this month was colder. The new bill was ~£130 for just electricity (about 100kWh more than last January) now that gas has gone. The previous January's bill was ~£160 of which ~£50 was gas. In effect ~100kWh of electricity more than substituted for ~500kWh of gas: an effective CoP of ~5, maybe, though ~100kWh of Thermino CoP 1 storage was being avoided too this month. Allowing for that suggests the equivalent of a ~200kWh rise in electricity against a ~600kWh fall in gas, ie an overall CoP of ~3. (Note that the months' billing days were slightly different, and the electricity unit rate fell but the standing rate rose.) For the month reported hph4 was 204kWh at ~89% coverage. Linear regression of hph4 against HDD12 yields n=28, slope=0.96kWh/HDD12, intercept=0.07kWh, R^2=0.87. Due to an Eddi firmware fault between ~23rd and 28th, the underlying reported consumption data is partly wrong in that interval or entirely absent. Avoiding partial dubious data for those days yields n=25, slope=0.87kWh/HDD12, intercept=1.07kWh, R^2=0.88. The Enphase emailed monthly report for January (triggered ) says: produced (generated) 58.5kWh (max 4.8kWh on the 30th), consumed 425.9kWh (max 18.0kWh on the 4th), grid energy imported 378.7kWh and exported 0.1kWh, grid dependence 90% (min 68% on the 30th). HDD12=235 vs 199 last January. |
| 2025-02 | 353 (12.6/d) | -110 (-3.9/d) | 20250131T18:00Z to 20250228T18:20 (28d) | Meter readings: electricity generation 110.3kWh, export 6.0kWh, import 248.2kWh (thus net consumption (I+G-E) 352.5kWh, self consumption ((N-I)/N) 30%). The Ecotricity bill for this month was ~£20 lower than last February's even though this month was colder. For the month hph4 was 182kWh. Linear regression of hph4 against HDD12 yields n=28, slope=0.58kWh/HDD12, intercept=2.76kWh, R^2=0.64. The Enphase emailed monthly report for February (triggered ) says: produced (generated) 111.2kWh (max 10.1kWh on the 28th), consumed 333.7kWh (max 22.2kWh on the 16th), grid energy imported 244.8kWh and exported 4.8kWh, grid dependence 73% (min 32% on the 18th). HDD12=180 vs 91 last February. |