# Electricity meter usage log — HomeEnergy Log

Canonical: https://getecoback.com/en/workbench/homeenergy-log.html
Language: en
Method version: 2026-09-19.2

Turn cumulative meter readings into interval use and daily averages.

## How this tool works

Interval kWh = current reading − previous reading for the same meter. Daily use = interval kWh ÷ elapsed days. A decreasing reading requires review.

## Input format

- Meter readings: `date,meter,reading_kwh`

## Reproducible example

All prefilled business examples are fictional. Replace them with your own checked inputs.

```json
{
  "columns": [
    "Date",
    "Meter",
    "Cumulative kWh",
    "Interval kWh",
    "kWh / day"
  ],
  "rows": [
    [
      "2026-08-01",
      "Main",
      12000,
      "Baseline",
      "Not comparable"
    ],
    [
      "2026-09-01",
      "Main",
      12220,
      "220.000",
      "7.097"
    ],
    [
      "2026-09-19",
      "Main",
      12360,
      "140.000",
      "7.778"
    ]
  ]
}
```

## Limits and assumptions

A decreasing reading is a reset or data error, never negative consumption. First reading is a baseline. Intervals are normalized by elapsed days, not compared as equal-length months.

Records stay on this device only when you choose Save. Export a backup before clearing browser storage.

Browser-based tools · Your inputs stay in this browser. No account, cloud backup or paid membership is provided.

[RFC 4180 — CSV format](https://www.rfc-editor.org/rfc/rfc4180)