The numbers behind it
Every settled figure the dashboard is built from. Check the arithmetic.
Solar & battery installed by Heatable
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How to read this
Every row is built from settled half hours: a meter reading joined to the tariff price in force at that moment, joined to what the inverter was doing. Half-hours is how many went into the row — a month showing fewer than it should have is missing data, and the figure beside it is short by however much is missing.
Would have paid costs the same household demand with no panels and no battery, at the rate actually in force. Total benefit is that minus what was really paid net of export, so it already contains the export earnings — which is why saved on bills and earned are shown separately and sum to it, rather than being added on top.
EV charging is excluded from savings: the charger is grid-only and invisible to the inverter, so its energy costs the same in every scenario and is reported on its own. Heating is not excluded — the radiators sit behind the inverter, so solar and the battery genuinely offset them. Standing charges are excluded throughout; you pay them either way. For this period they came to £169.97.
| Month | Half-hours | Solar kWh | Used kWh | Imported kWh | Exported kWh | Batt in kWh | Batt out kWh | EV kWh | Heating kWh | Would have paid | Import cost | Paid net of export | Saved on bills | Earned | Total benefit | EV cost |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Apr 2025 | 1,152 / 1440 | 621.1 | 1,020.2 | 673.9 | 0.0 | 579.1 | 287.5 | 184.5 | 504.4 | £266.42 | £118.88 | £118.88 | £147.55 | £0.00 | £147.55 | £25.59 |
| May 2025 | 1,488 | 1,501.2 | 1,008.4 | 380.7 | 754.3 | 398.6 | 279.4 | 135.3 | 269.8 | £251.59 | £52.56 | −£60.58 | £199.03 | £113.15 | £312.18 | £20.05 |
| Jun 2025 | 1,440 | 1,581.9 | 722.8 | 672.9 | 1,478.9 | 527.4 | 474.3 | 213.8 | 104.8 | £172.30 | £60.76 | −£161.08 | £111.55 | £221.83 | £333.38 | £26.55 |
| Jul 2025 | 1,488 | 1,453.7 | 592.6 | 764.8 | 1,580.2 | 602.6 | 556.9 | 275.1 | 14.8 | £135.16 | £60.63 | −£176.40 | £74.53 | £237.03 | £311.56 | £20.43 |
| Aug 2025 | 1,488 | 1,270.3 | 556.9 | 789.0 | 1,447.7 | 621.2 | 566.6 | 152.7 | 15.0 | £125.80 | £63.21 | −£153.95 | £62.59 | £217.16 | £279.75 | £15.69 |
| Sep 2025 | 1,440 | 842.8 | 921.8 | 885.0 | 737.8 | 725.4 | 657.3 | 117.9 | 214.2 | £219.84 | £83.74 | −£26.93 | £136.10 | £110.67 | £246.77 | £13.47 |
| Oct 2025 | 1,488 | 458.3 | 1,273.9 | 1,074.6 | 240.2 | 686.8 | 668.0 | 227.3 | 485.4 | £312.67 | £134.00 | £97.97 | £178.67 | £36.04 | £214.71 | £36.39 |
| Nov 2025 | 1,440 | 254.9 | 1,591.5 | 1,453.4 | 111.8 | 591.7 | 586.7 | 312.8 | 911.1 | £407.64 | £246.92 | £230.16 | £160.72 | £16.77 | £177.49 | £42.28 |
| Dec 2025 | 1,488 | 163.8 | 2,090.5 | 2,014.8 | 70.6 | 602.8 | 585.2 | 191.9 | 1,140.0 | £550.92 | £397.60 | £387.00 | £153.32 | £10.59 | £163.91 | £31.98 |
| Jan 2026 | 1,488 | 131.8 | 2,228.3 | 2,147.2 | 59.3 | 383.1 | 391.8 | 292.8 | 1,349.7 | £540.60 | £435.70 | £426.80 | £104.90 | £8.90 | £113.80 | £46.97 |
| Feb 2026 | 1,344 | 281.4 | 1,840.0 | 1,668.7 | 93.7 | 549.0 | 532.6 | 169.7 | 1,122.6 | £454.57 | £290.71 | £276.66 | £163.86 | £14.06 | £177.91 | £23.98 |
| Mar 2026 | 1,488 | 781.7 | 1,738.4 | 1,175.8 | 197.3 | 694.2 | 672.4 | 256.8 | 976.2 | £449.57 | £172.12 | £148.45 | £277.45 | £23.68 | £301.12 | £32.08 |
| Apr 2026 | 288 / 1440 | 107.9 | 332.6 | 258.9 | 29.0 | 121.2 | 116.0 | 0.0 | 207.4 | £85.90 | £38.94 | £35.46 | £46.95 | £3.48 | £50.44 | £0.00 |
| Total | 17,520 | 9,450.8 | 15,917.9 | 13,959.7 | 6,800.9 | 7,083.0 | 6,374.6 | 2,530.6 | 7,315.3 | £3,973.00 | £2,155.78 | £1,142.43 | £1,817.21 | £1,013.35 | £2,830.56 | £335.45 |