The Shelly Presence Gen4 is a mmWave radar-based presence sensor designed for advanced multi-occupant detection in smart homes, capable of tracking up to 6 separate people simultaneously across customizable detection zones. Unlike traditional motion sensors that rely on movement, this device detects true presence even when people sit motionless—a critical difference for bedrooms, offices, and living rooms where occupants spend long periods without moving.
Key Takeaways
- Tracks up to 6 people at once using mmWave radar technology, not motion detection
- Covers up to 42 m² with 10 customizable detection zones for precise area-based automation
- Includes ambient light sensor, fall detection, and standstill detection features
- Privacy-friendly alternative to cameras; supports Wi-Fi, Bluetooth, Zigbee 3.0, and Matter
- USB-C powered with no battery required for continuous operation
How Shelly Presence Gen4 Outperforms Motion Sensors
Traditional motion sensors like the Shelly Motion 2 detect movement up to 9 meters but cannot distinguish between multiple people or track stillness. The Shelly Presence Gen4 solves this by using mmWave radar, which penetrates walls and detects bodies regardless of activity level. This matters in real-world scenarios: a parent reading silently in a bedroom, an office worker focused on a screen, or multiple family members in an open-plan living area all register as distinct occupants, not as motion events.
The sensor’s adjustable sensitivity prevents false triggers from pets or robot vacuums—a common frustration with basic PIR detectors. For homes with dogs or cats, this feature eliminates the annoying automation hiccups that plague cheaper motion-based systems.
Shelly Presence Gen4 Zone Mapping and Real-Time Visualization
The device supports up to 10 customizable detection zones, allowing you to assign different automations to different areas of a room. A kitchen with an island can trigger lights only over the cooking area, leaving the dining section dark. A large bedroom can activate subtle lighting near the bed while keeping the rest of the room unlit. This granularity is impossible with single-zone motion sensors.
Real-time visualization on a map shows exactly where detected people are positioned, giving you space awareness that basic occupancy sensors cannot provide. This precision enables energy-efficient automations: lights turn on only in occupied zones, and appliances power down when the room empties completely.
Features Beyond Basic Presence Detection
The Shelly Presence Gen4 includes a built-in ambient light sensor that detects dark, dim, and bright conditions, triggering context-aware scenes. Imagine twilight soft lighting that activates automatically when brightness drops, or morning scenes that adjust based on natural light levels. The sensor also features standstill detection and fall detection for safety, making it useful in elderly care or accessibility scenarios.
Connectivity is comprehensive: Wi-Fi, Bluetooth, Zigbee 3.0, and Matter-ready via firmware update. Alexa compatibility means voice control integration for users in Amazon’s ecosystem. USB-C power (5V DC, max 1A) eliminates battery replacement hassles—a practical advantage over the Shelly BLU Motion, which requires periodic battery changes despite its 5-year lifespan.
Privacy and Use Cases for Multi-Occupant Homes
The Shelly Presence Gen4 is privacy-friendly by design, requiring no camera to detect presence. This makes it ideal for bedrooms, bathrooms, and other spaces where video surveillance raises privacy concerns. Multi-occupant homes benefit most: open-plan living areas, shared offices, and family bedrooms can now trigger automations that respond to the actual number of people present, not just binary motion detection.
Hands-free room automation becomes realistic when the system knows if you’re sitting still. Enter a bedroom and the lights adjust; leave entirely and they turn off. Add another person and the system adapts without requiring manual overrides. This is automation that feels intelligent rather than reactive.
What Sets Shelly Presence Gen4 Apart from Competitors
The Shelly Motion 2, Shelly’s own motion-focused alternative, detects movement up to 9 meters but lacks multi-person tracking and stillness detection. It does include temperature and light sensors plus a 6500mAh battery lasting 12–18 months, making it suitable for battery-powered locations. However, the Shelly Presence Gen4’s continuous USB power and mmWave radar capability make it the clear choice for rooms where multiple people occupy the same space simultaneously.
Other Shelly Gen4 devices like the Flood Gen4 focus on water leak detection, not presence. The Presence Gen4 stands alone in its multi-occupant capability within the Shelly ecosystem.
Is Shelly Presence Gen4 Worth Installing?
If your home has open-plan layouts, shared offices, or multi-occupant bedrooms, the Shelly Presence Gen4 delivers automations impossible with motion sensors. The 10-zone customization and 6-person tracking eliminate the false negatives and false positives that plague simpler systems. For privacy-conscious users, it offers occupancy intelligence without cameras. The trade-off is USB-C power dependency—you need an outlet nearby, unlike battery-powered alternatives.
Can the Shelly Presence Gen4 detect people through walls?
Yes, mmWave radar penetrates walls and solid objects, allowing the sensor to detect presence in adjacent spaces. This is useful for detecting occupancy in rooms beyond the sensor’s direct line of sight, though sensitivity and accuracy decrease with distance and obstruction.
How does the light sensor feature improve automation?
The ambient light sensor detects dark, dim, and bright conditions, enabling scenes that respond to natural light levels. Soft lighting triggers at dusk without requiring manual scheduling, and daytime automations can suppress lights when the room is already bright, saving energy.
What’s the coverage area of Shelly Presence Gen4?
The sensor covers up to 42 m², making it suitable for larger rooms and open-plan areas. This coverage, combined with 10 customizable zones, allows precise control in spaces where traditional single-zone motion sensors fail.
The Shelly Presence Gen4 represents a meaningful step forward for smart home automation in multi-occupant spaces. It moves beyond the binary motion-or-no-motion paradigm to recognize the complexity of real homes where multiple people coexist in the same room. For anyone tired of lights flickering when someone sits still, or automations triggering from pet movement, this sensor delivers the presence awareness that smarter homes actually need.
Where to Buy
3 Amazon customer reviews | £39.99
Edited by the All Things Geek team.
Source: T3
