Solutions — Power metering
Electricity consumption monitoring at 15 minutes
Carmilla turns the totaliser of an energy meter into a 15-minute load profile with ARERA bands and a monthly anchor, and shows live three-phase telemetry without archiving the noise.
01 — What it solves
From the totaliser to the curve
Load profile computed by the platform
The meter sends its totaliser every minute; the platform closes the quarter hours and the monthly anchor. About 96 records a day instead of 1,440 frames.
Three-phase, live
Power, current, voltage, frequency and power factor per phase in real time over WebSocket, without persisting every sample.
Honest gaps, no fake peaks
If the meter goes offline, the accumulated energy is not attributed to the quarter it comes back in: daily and monthly totals stay exact.
02 — How it works
How monitoring works
01
Energy meters
Three-phase Shelly Pro 3EM, with imported and returned active energy per phase and total.
02
MQTT broker and collector
Meter messages go from the MQTT broker to a collector that delivers them to the platform.
03
Consolidation
The value at the quarter boundary is the last sample before it; the quarter closes on the first sample of the next one.
04
Dashboard and API
15-minute curve and monthly table in the dashboard; the same queries as the DLMS profiles through the API, with 14 aggregation levels.
03 — Specifications
Under the hood
- Devices
- Shelly Pro 3EM (Gen2, three-phase, JSON-RPC over MQTT); designed for the other Shelly generations
- Streams
- Energy every 60 s (durable), three-phase telemetry ~16 s (live only), heartbeat, presence
- Data
- 15-min imported/returned curve in kWh with ARERA band, monthly totaliser anchor
- Integration
- REST API /v1/power: devices, profile, billing; realtime over WebSocket
04 — Regulation and obligations
Monitoring consumption is part of the efficiency obligations
Italian D.Lgs. 102/2014, art. 8 and Directive (EU) 2023/1791, art. 11
Energy audit every four years above 10 TJ of consumption, energy management system above 85 TJ: without 15-minute measurements the audit stays on the bills.
ISO 50001
The energy management system requires performance indicators measured and monitored over time: the load profile per point is the basic indicator.
EN 16247-1
Energy audit methodology: collection of measured data, load profiles and verification of savings. Data has to be collected beforehand, not reconstructed afterwards.
ARERA time bands F1/F2/F3 (Resolution 181/06)
Tariff bands determine the cost of energy: the platform stamps them on every quarter hour with Italian holidays, so the comparison with the bill is direct.
Indicative references, current at publication date: they do not replace a regulatory check for your case.
05 — Frequently asked questions
Frequently asked questions on electricity monitoring
Which meters can I use?
Shelly Pro 3EM today; the chain is designed to cover the other Shelly generations and to converge Chain2 data onto the same engine.
Do you also have reactive energy?
The meter has no reactive totaliser: reactive power is derived for display, while reactive energy is not populated in the curve.
What if the meter is offline for hours?
Live reconstruction covers windows up to about 4 hours; beyond that the gap stays visible and totals are not invented.
How do I use the curve in my system?
Through the REST API with per-tenant tokens, with the same semantics as the DLMS profiles: range, aggregation, physical or raw values.