The Fusion Energy SEM-Meter is a budget in-panel monitor that clips sensors onto your mains and up to 16 individual circuits, and shows usage in a phone app or locally in Home Assistant. It typically sells for $135 to $150 on Amazon.
Wondering how an energy monitor fits with a smart thermostat, EV charger or backup battery? Our Whole-Home Energy Calculator adds up the whole setup: the electricity it adds or saves each month and the net change on your bill.
What you can track
Pick the circuits that matter most, such as HVAC, water heater, dryer, range or EV charger. Anything you leave unclamped only appears in the whole-home total.
- Whole home and circuits: mains clamps plus 16 circuit clamps
- Solar: energy in and out, for net metering
- Costs: time-of-use rate templates by day and hour
- Shared homes: split costs per room or circuit, handy for a rental unit
Local mode and installation
Privacy Mode sends readings to your own MQTT server for Home Assistant or Hubitat, every 2 seconds on firmware 3.0.5 or newer. Owners report it keeps working on a network with no internet access. The meter mounts inside your breaker panel with snap-on clamps, so hire a licensed electrician unless you’re trained for panel work.
How it compares
| Fusion Energy SEM-Meter | Emporia Vue 3 | Refoss EM16P | |
|---|---|---|---|
| Typical price | $135 to $150 | $100 to $200 | $160 to $200 |
| Circuit sensors | 16 x 50A | 16 x 50A | 16 x 60A |
| Mains sensors | Included | 2 x 200A | 2 x 200A |
| Local, no-cloud mode | Yes: MQTT for Home Assistant | No, cloud app | Yes: web UI, Home Assistant, MQTT |
| Connection | 2.4GHz Wi-Fi | Wi-Fi or Ethernet | 2.4GHz Wi-Fi |
| Warranty | 1 year | 1 year | 2 years |
| Best for | Low-cost 16 circuits, local data | Most homes wanting a polished app | Local data from a better-documented brand |
See my Emporia Vue 3 and Refoss EM16P reviews.
Want to see other Energy Monitors? Compare them side by side →
How I researched this: Fusion Energy’s Amazon and retailer listings, a Home Assistant integration guide on GitHub, and owner reports in the Home Assistant and Hubitat communities. Prices checked September 30, 2026.
Fusion Energy SEM-Meter
Fusion Energy SEM-Meter review: 16 circuit sensors, local MQTT for Home Assistant and no subscription for about $120. What it tracks and alternatives.
Product Brand: Fusion Energy
4.4