Energy Monitoring

Sowel includes built-in energy monitoring that tracks your home's electricity consumption and (optionally) your solar production over time. It supports peak / off-peak tariff classification, autoconsumption tracking, and a by-usage breakdown when you instrument dedicated circuits.

The three energy equipment types

Energy monitoring in Sowel is integration-agnostic. Any plugin that reports energy or power data on a device can feed the energy pipeline, as long as the device is bound to one of these three equipment types.

Equipment type	What it represents	Required device data
main_energy_meter	Your main grid meter (whole-home import / export)	Cumulative energy (Wh), or a signed grid energy delta per tick
energy_meter	A submeter on a dedicated circuit (heat pump, pool, EV charger, ...)	Cumulative energy (Wh) or instantaneous power (W)
energy_production_meter	Your solar (or other local production) meter	Cumulative production energy (Wh)

You can mix and match: a setup with only a main meter is fine, you do not need solar to use the Energy page. Conversely, you can have many submeters without a main meter — you will just lose the "Other" residual on the by-usage view.

Power-only submeters

Cheap zigbee clamps that report only power (W) and not energy (Wh) are supported for submeters. Sowel integrates the power signal locally into a Wh stream attributed to the submeter equipment, with the same per-minute cadence as the main meter. State survives restarts.

How the data flows

Energy meter device (any integration)
  -> Plugin reports `energy` (Wh) or `power` (W)
    -> HistoryWriter writes per-minute points to InfluxDB
      -> EnergyAggregator computes hour / day / month / year cumuls
        -> Energy page renders charts and totals

InfluxDB stores raw points in a short-retention bucket, then automatic downsampling tasks aggregate them into hourly and daily buckets with much longer retention. The Energy page picks the right bucket transparently based on the time range you are looking at.

InfluxDB is automatic

InfluxDB is mandatory and starts with Sowel via Docker Compose. On first launch, Sowel auto-creates the required buckets, downsampling tasks, and energy aggregation tasks. No manual InfluxDB configuration is needed.

Setting up energy monitoring

Step 1: Connect an energy integration

Install a plugin that provides energy meter devices (browse the catalogue from Administration > Plugins) and configure it from Administration > Integrations. Any plugin that surfaces a device exposing energy or power data is eligible.

Step 2: Create the main energy meter equipment

Go to Administration > Equipments and create an equipment:

• Type: Main Energy Meter
• Zone: typically the Home root, or a Utility zone
• Bind to your grid meter device's energy data

Once bound, Sowel starts writing one energy point per minute to InfluxDB.

Step 3: (Optional) Add a production meter

If you have local production (solar panels typically), create an equipment of type Energy Production Meter and bind it to your production meter device. With both a main meter and a production meter in place, Sowel computes:

• Grid consumption: energy drawn from the grid
• Autoconsumption: energy produced and consumed in the house
• Grid injection: energy produced and pushed to the grid
• Total consumption: grid + autoconsumption

Step 4: (Optional) Configure peak / off-peak tariffs

If your electricity plan splits hours into peak and off-peak, configure the schedule so Sowel can break down your consumption.

Go to Settings > Administration > Energy tariffs:

1. Optionally enter your peak and off-peak prices per kWh (used for cost views; classification works without them)
2. Define your time slots: which hours are peak and which are off-peak
3. You can add as many slots as you need to cover the 24 hours of the day

If no tariff is configured, all consumption is classified as peak by default — you simply do not see the split.

Step 5: (Optional) Add submeters for a by-usage breakdown

To know how your main meter's consumption splits across circuits, add an energy_meter equipment for each circuit you instrument.

1. Install a zigbee energy clamp, smart plug, or Wi-Fi meter on the dedicated circuit
2. Go to Administration > Equipments and create an equipment of type Energy Meter
3. Bind it to the device's energy (Wh) data, or — if your device reports only power (W) — to its power data: Sowel integrates the power signal into a Wh stream automatically

Once at least one submeter is configured, the By usage toggle appears on the Consumption page. The toggle is hidden when no submeter exists.

Using the Energy section

The sidebar groups the energy views under Energy:

• Live: instant flow between grid, production, and house consumption
• Consumption: historical consumption with peak / off-peak split and self-consumption overlay
• Production: historical solar production with autoconsumption / injection split

Live view

The Live view shows what is happening right now — power values updated in real time via WebSocket.

The diagram shows three boxes (Grid, Consumption, Production) with arrows indicating the direction of energy flow. When solar production exceeds in-house consumption, a "Solar surplus" indicator appears, and the share of solar going to the grid versus to the house is shown on the arrows.

Tiles are hidden when their underlying equipment is not configured: with no production meter, only Grid and Consumption are shown.

Consumption view

Pick a period (Day, Week, Month, Year) and navigate dates with the arrows. The chart renders bars for each time bucket of the selected period.

Color coding on the Total chart:

Color	Meaning
Dark blue	Peak-hours grid consumption
Light blue	Off-peak-hours grid consumption
Green	Autoconsumption (only when a production meter is set up)

Below the chart, totals are shown in kWh: grid (split into peak / off-peak), autoconsumption, and total (with the self-consumption share as a percentage).

Total / By usage toggle

When at least one submeter is configured, a Total / By usage toggle appears above the chart. The By usage view replaces the peak / off-peak split with one stack per submeter, plus an Other stack for the residual that the main meter saw but no submeter accounted for.

Submeters use a deterministic color palette so the same circuit keeps the same color across days and views. The "Other" stack is clamped at zero, so a submeter that briefly overshoots the main meter (due to sampling skew) cannot make it negative.

Totals widgets (peak / off-peak, autoconsumption) stay unchanged when you toggle modes.

Longer periods

Switching to Month or Year keeps the same colors and totals, but each bar represents a day (Month view) or a month (Year view).

Production view

The Production page renders solar (or other local production) history:

Color	Meaning
Light green	Autoconsumption — produced and consumed locally
Dark green	Grid injection — produced and pushed back to the grid

Totals below the chart sum the two slices into the day's, month's, or year's total production.

Data pipeline

Understanding how data flows helps with troubleshooting:

Plugin reports energy or power
  -> per-minute energy points written to InfluxDB "sowel" bucket  (7-day retention)
    -> sowel-energy-sum-hourly task
      -> "sowel-energy-hourly" bucket  (2-year retention)
        -> sowel-energy-sum-daily task
          -> "sowel-energy-daily" bucket  (10-year retention)

The Energy page chooses the bucket based on the period:

• Day view for today and recent days: queries the raw bucket for real-time accuracy
• Day view for older days: queries the hourly bucket
• Month / Year: queries the daily bucket for fast, long-range queries

The aggregator also keeps in-memory cumuls (hour, day, month, year) that the Live view and Home page widgets read directly, refreshed on every new energy tick.

Troubleshooting

No data appears on the Energy page

1. Check that the integration providing your energy meter device is connected (green indicator in Administration > Integrations)
2. Verify the equipment exists (Main Energy Meter and/or Energy Production Meter) and is bound to a device that actually emits energy data
3. Wait for at least one polling / push cycle — exact frequency depends on the plugin, but typically a few minutes at most
4. Check Settings > System > Logs for messages from the history-writer or energy-aggregator modules

Peak / off-peak shows everything as peak

This means no tariff schedule is configured. Go to Settings > Administration > Energy tariffs and define your slots.

Old data is missing

Data older than 7 days lives only in the downsampled hourly and daily buckets. If those buckets are empty, the downsampling tasks have not run yet (they run once per hour and once per day). Check that InfluxDB is running and reachable, and inspect the logs of the history-writer module on startup — Sowel logs whether the tasks were created or already existed.

By usage view shows a large "Other" residual

This means your submeters do not cover most of the main meter's consumption — which is normal: the main meter sees everything in the house, while submeters typically cover specific high-power circuits. The residual is "Other circuits".

If the residual is negative (clamped to zero in the chart), one of your submeters is reporting more than the main meter sees — usually a clamp wired backwards or a calibration mismatch. The integrator clamps negative power deltas at zero and logs a WARN once per occurrence.