Earth Notes: Saving Electricity and Gas (2024)
Updated 2024-12-14.Meter readings at home. #4kWhDHWClub
Meter readings and analysis of our electricity and gas carbon footprint at home in 2024.
2024
See the daily PV generation logs for 2024 as .csv and .png chart.
Heat Pump This Year?
Given that our old-ish gas combi boiler continues to struggle, I requested an on-line Octopus heat-pump quote and got in the queue.
If we do get a heat pump that will be our last use of gas gone, and we could maybe have it disconnected to avoid the standing charge.
In any case, the replacement would likely push our energy carbon footprint back negative, as I had hoped for when installing the solar PV.
2024-11-27: Gas Supply Capped; Pumped!
The gas supply was capped today, with the meter bagged up awaiting pickup by our supplier. Our heat-pump install should be complete tomorrow.
Although there is no more gas to save, for now the final gas reading will be carried forward as-is in various places to keep data management simple.
The heat pump was fully up and running by the end of the month, though I will be tweaking settings forever...
| 2024 | Electricity | Gas | |||
|---|---|---|---|---|---|
| Month | Consumed kWh (/d) | Generated -kWh (/d) | Consumed kWh (/d) | Period | Notes |
| 2024-01 | 328 (10.6/d) | -74 (-2.4/d) | 495 (16.0/d) | 20231231T16:13Z to 20240131T18:23Z (31d) | Meter readings: electricity generation 74.3kWh, export 0.7kWh, import 253.9kWh (thus net consumption (I+G-E) 327.5kWh, self consumption ((N-I)/N) 22%); gas ~44.6m^3 (so 495.2kWh @ 11.1kWh/m^3). The kitchen MHRV motor was replaced and is now quiet again. The Enphase emailed monthly report for January (triggered 2024-02-01) says: produced (generated) 74.5kWh (max 4.4kWh on the 26th), consumed 319.8kWh (max 17.6kWh on the 20th), grid energy imported 261.5kWh and exported 0.3kWh, grid dependence 82% (min 50% on the 18th). HDD12=199 vs 194 last January. |
| 2024-02 | 328 (11.3/d) | -112 (-5.6/d) | 191 (6.6/d) | 20240131T18:23Z to 20240229T18:04Z (29d) | Meter readings: electricity generation 111.9kWh, export 4.5kWh, import 220.1kWh (thus net consumption (I+G-E) 327.5kWh, self consumption ((N-I)/N) 33%); gas ~17.2m^3 (so 191.1kWh @ 11.1kWh/m^3). This appears to be the warmest February at 16WW/EGLL at least since 2007, going by HDD12. My son went skiing with school to Italy, by coach (~24h out, ~18h return). The Enphase emailed monthly report for February (triggered 2024-03-01) says: produced (generated) 113.2kWh (max 7.8kWh on the 27th), consumed 305.3kWh (max 16.0kWh on the 2nd), grid energy imported 213.4kWh and exported 3.5kWh, grid dependence 70% (min 16% on the 24th). HDD12=91 vs 145 last February. |
| 2024-03 | 306 (9.9/d) | -256 (-8.3/d) | 90 (2.9/d) | 20240229T18:04Z to 20240331T19:22Z (31d) | Meter readings: electricity generation 256.0kWh, export 45.5kWh, import 162.0kWh (thus net consumption (I+G-E) 305.5kWh, self consumption ((N-I)/N) 47%); gas ~8.1m^3 (so 90.3kWh @ 11.1kWh/m^3). Passed 44MWh generated from the first 3/4ths of the grid-tied PV. The Enphase emailed monthly report for March (triggered 2024-04-01) says: produced (generated) 256.8kWh (max 16.5kWh on the 30th), consumed 343.8kWh (max 17.6kWh on the 1st), grid energy imported 158.6kWh and exported 42.8kWh, grid dependence 46% (min 1% on the 31st). HDD12=100 vs 129 last March. |
| 2024-04 | 331 (11.0/d) | -406 (-13.5/d) | 14 (0.5/d) | 20240331T19:22Z to 20240430T14:49Z (30d) | Meter readings: electricity generation 405.5kWh, export 131.3kWh, import 56.8kWh (thus net consumption (I+G-E) 331.0kWh, self consumption ((N-I)/N) 83%); gas ~1.3m^3 (so 14.2kWh @ 11.1kWh/m^3). The Enphase emailed monthly report for April (triggered 2024-05-01) says: produced (generated) 412.0kWh (max 24.1kWh on the 30th), consumed 312.1kWh (max 15.5kWh on the 7th), grid energy imported 52.0kWh and exported 129.8kWh, grid dependence 17% (min 2% on the 26th). HDD12=67 vs 87 last April. |
| 2024-05 | 299 (9.6/d) | -464 (-15.0/d) | 16 (0.5/d) | 20240430T14:49Z to 20240531T18:07Z (31d) | Meter readings: electricity generation 464.1kWh, export 204.9kWh, import 39.8kWh (thus net consumption (I+G-E) 299.0kWh, self consumption ((N-I)/N) 87%); gas ~1.4m^3 (so 15.5kWh @ 11.1kWh/m^3). The Enphase emailed monthly report for May (triggered 2024-06-02) says: produced (generated) 462.6kWh (max 25.8kWh on the 20th), consumed 276.6kWh (max 14.5kWh on the 17th), grid energy imported 35.8kWh and exported 201.8kWh, grid dependence 13% (min 1% on the 27th). HDD12=9 vs 20 last May. |
| 2024-06 | 312 (10.4/d) | -570 (-19.0/d) | 18 (0.6/d) | 20240531T18:07Z to 20240630T16:55Z (30d) | Meter readings: electricity generation 570.4kWh, export 284.7kWh, import 26.3kWh (thus net consumption (I+G-E) 312.0kWh, self consumption ((N-I)/N) 92%); gas ~1.5m^3 (so 17.7kWh @ 11.1kWh/m^3). Exports passed 41MWh. Generation passed 45MWh on the first array and 14MWh on the second. The Enphase emailed monthly report for June (triggered 2024-07-01) says: produced (generated) 573.8kWh (max 27.9kWh on the 20th), consumed 293.9kWh (max 15.4kWh on the 7th), grid energy imported 21.3kWh and exported 282.7kWh, grid dependence 7% (min 1% on the 29th). HDD12=8 vs 3 last June. |
| 2024-07 | 265 (8.5/d) | -545 (-17.6/d) | 12 (0.4/d) | 20240630T16:55Z to 20240731T20:41Z (31d) | Meter readings: electricity generation 544.5kWh, export 298.1kWh, import 18.2kWh (thus net consumption (I+G-E) 264.6kWh, self consumption ((N-I)/N) 93%); gas ~1.1m^3 (so 12.4kWh @ 11.1kWh/m^3). Most of family away from the end of the month on the west coast of Canada, ~9tCO2 for the round-trip. As of the end of the month, Ecotricity predicts ~£200/y gas plus ~£600/y electricity from when rates drop. Installing a heat-pump would change that! The Enphase emailed monthly report for July (triggered 2024-08-01) says: produced (generated) 564.3kWh (max 26.6kWh on the 4th), consumed 245.5kWh (max 13.8kWh on the 4th), grid energy imported 14.3kWh and exported 296.6kWh, grid dependence 6% (min 1% on the 26th). HDD12=0 vs 0 last July. |
| 2024-08 | 189 (6.1/d) | -490 (-15.8/d) | 7 (0.2/d) | 20240731T20:41Z to 20240831T17:15Z (31d) | Meter readings: electricity generation 490.0kWh, export 312.0kWh, import 10.8kWh (thus net consumption (I+G-E) 188.8kWh, self consumption ((N-I)/N) 94%); gas ~0.6m^3 (so 6.7kWh @ 11.1kWh/m^3). The family was away in various combinations for parts this month, thus consumption is lower than 'normal'. Work is underway with Octopus to try to get an ASHP (Air Source Heat Pump, for space heat and DHW) fitted before the heating season starts, potentially eliminating significant further gas use. The Enphase emailed monthly report for August (triggered 2024-09-01) says: produced (generated) 492.8kWh (max 22.9kWh on the 17th), consumed 173.3kWh (max 11.2kWh on the 15th), grid energy imported 9.2kWh and exported 312.7kWh, grid dependence 5% (min 1% on the 5th). HDD12=0 vs 1 last August. |
| 2024-09 | 291 (9.7/d) | -287 (-9.6/d) | 13 (0.4/d) | 20240831T17:15Z to 20240930T17:17Z (30d) | Meter readings: electricity generation 287.2kWh, export 75.5kWh, import 79.1kWh (thus net consumption (I+G-E) 290.8kWh, self consumption ((N-I)/N) 73%); gas ~1.2m^3 (so 13.3kWh @ 11.1kWh/m^3). Ellie has left for university, so occupancy at 16WW is now 3. Work continues with Octopus, with design-day (-1.8°C) whole-home heat demand recalculated to be ~2kW. Heating not yet on and gas use for DHW still being aggressively restrained by the heat-battery grid top-up settings. The Enphase emailed monthly report for September (triggered 2024-10-01) says: produced (generated) 288.6kWh (max 18.5kWh on the 13th), consumed 273.0kWh (max 15.8kWh on the 8th), grid energy imported 76.9kWh and exported 73.2kWh, grid dependence 28% (min 6% on the 16th). HDD12=16 vs 1 last September. |
| 2024-10 | 291 (9.3/d) | -152 (-4.9/d) | 8 (0.3/d) | 20240930T17:17Z to 20241031T18:15Z (31d) | Meter readings: electricity generation 151.9kWh, export 9.3kWh, import 150.9kWh (thus net consumption (I+G-E) 290.8kWh, self consumption ((N-I)/N) 48%); gas ~0.7m^3 (so 8.3kWh @ 11.1kWh/m^3). Passed 17MWh electricity imports from the grid on the current meter. The Enphase emailed monthly report for October (triggered 2024-11-01) says: produced (generated) 153.1kWh (max 10.6kWh on the 4th), consumed 267.6kWh (max 14.9kWh on the 8th), grid energy imported 146.9kWh and exported 10.2kWh, grid dependence 55% (min 23% on the 28th). HDD12=27 vs 28 last October. |
| 2024-11 | 259 (8.6/d) | -57 (-1.9/d) | 47 (1.6/d) | 20241031T18:15Z to 20241130T22:28Z (30d) | Meter readings: electricity generation 56.5kWh, export 0.9kWh, import 203.6kWh (thus net consumption (I+G-E) 259.2kWh, self consumption ((N-I)/N) 21%); gas ~4.3m^3 (so 47.3kWh @ 11.1kWh/m^3). The gas boiler was replaced with a heat pump at the end of the month! No more fossil fuels for heating! The gas supply was capped . The heat pump was fully operational by for DHW and space heating. The heat battery was disconnected , and with other things gas contributed more to DHW than usual until the gas boiler was removed . The Enphase emailed monthly report for November (triggered 2024-12-01) says: produced (generated) 56.2kWh (max 4.6kWh on the 11th), consumed 240.0kWh (max 18.2kWh on the 28th), grid energy imported 198.9kWh and exported 0.2kWh, grid dependence 83% (min 45% on the 20th). HDD12=113 vs 114 last November. |