Refoss
Refoss EM16P Smart Energy Monitor
$199.99Cheaper
Best Home Energy Monitors · head-to-head
Refoss EM16P Smart Energy Monitor vs IotaWatt Open WiFi Energy Monitor
A sourced, side-by-side comparison. Refoss EM16P Smart Energy Monitor is cheaper at $199.99. Every spec and price links to its source.
IotaWatt / CircuitIQ
IotaWatt Open WiFi Energy Monitor
$389
Which is better: the Refoss EM16P Smart Energy Monitor or IotaWatt Open WiFi Energy Monitor?
On the specs we track, they're closely matched. The Refoss EM16P Smart Energy Monitor is the cheaper at $199.99.
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Full spec sheet
✓ marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.
| Spec | Refoss EM16P Smart Energy Monitor | IotaWatt Open WiFi Energy Monitor |
|---|---|---|
| US price | $199.99 | $389 |
| Brand | Refoss | IotaWatt / CircuitIQ |
| Released | — | — |
| Monitoring type | ct-clamp | ct-clamp |
| Main circuit amps | 200 | — |
| Branch circuit count | 16 | 14 |
| Connectivity protocol | Wi-Fi | Wi-Fi |
| Solar net metering | Yes | Yes |
| Local api support | Yes | Yes |
| Subscription required | No | No |
| App platforms | web UI (local), cloud optional | web (local) |
| Accuracy percent | 2 | — |
| Installation type | panel-mount | panel-mount |
| Smart home integrations | Home Assistant (native), MQTT | Home Assistant, Emoncms, PVOutput, InfluxDB |
| Etl ul certified | ETL (UL 61010) | ETL (UL + CSA) |
Sources — Refoss EM16P Smart Energy Monitor: refoss.net (verified 2026-06-27). IotaWatt Open WiFi Energy Monitor: stuff.iotawatt.com (verified 2026-06-27).
What's the difference between the Refoss EM16P Smart Energy Monitor and IotaWatt Open WiFi Energy Monitor?
Where the two actually differ on the specs we track (4 of 12). Matching specs are omitted.
- Branch circuit count: Refoss EM16P Smart Energy Monitor 16 vs IotaWatt Open WiFi Energy Monitor 14
- App platforms: Refoss EM16P Smart Energy Monitor web UI (local), cloud optional vs IotaWatt Open WiFi Energy Monitor web (local)
- Smart home integrations: Refoss EM16P Smart Energy Monitor Home Assistant (native), MQTT vs IotaWatt Open WiFi Energy Monitor Home Assistant, Emoncms, PVOutput, InfluxDB
- Etl ul certified: Refoss EM16P Smart Energy Monitor ETL (UL 61010) vs IotaWatt Open WiFi Energy Monitor ETL (UL + CSA)