What the literature actually says.

The behavioural baseline

Finding	Source
Fewer than 10% of hotel guests switch off the AC when leaving the room.	SensorFlow, "Hotels: Guests Are Using A/C All Wrong" (analysis of 64,000 room-nights)
~50% of post-check-in hours have AC running while the room is unoccupied.	SensorFlow, same dataset
54% of guests do not switch off AC when opening doors or windows.	SensorFlow, same dataset
Airbnb guests use ~3× more energy than the host of the same apartment.	M. Halford, single-unit comparative analysis (2022)

Peer-reviewed savings from occupancy-aware control

Study	Setting	HVAC savings
Pang et al. (2021), Journal of Building Performance Simulation	US large-hotel simulation, 19 climate zones	24–58%
US DOE / Pacific Northwest National Laboratory (2012)	Field study, hotel guest rooms	10–30% (avg 18.4%)
Building and Environment (2024)	Single-family homes, long-term presence-sensor test	15–69% (avg ~17%)
Applied Energy (2021)	Side-by-side hotel rooms, occupant-centric control	Significant; no IAQ or comfort loss

The convergent field median is 17–30% HVAC reduction. Our ROI calculator uses 22% (mid-range) as the conservative default; hotter climates and worse baseline behaviour push toward 30%. Simulation upper bounds reach ~58% but we deliberately do not advertise those numbers.

Mediterranean unit economics

Component	Range
Summer monthly electricity bill, 1–2 BR Greek STR	€150–300
AC share of summer electricity	40–60%
Realistic savings via occupancy-aware control (17–30% of HVAC)	22% baseline
Implied savings, peak summer month	€25–90/unit
Implied savings, 4 peak summer months	€100–360/unit
Annualised average savings	€80–250/unit

Year-by-year payback

Savings scenario	Year 1 net	Year 2+ net
Low (€80/yr savings)	−€140	−€40
Mid (€160/yr savings)	−€60	+€40
High (€250/yr savings)	+€30	+€130

Year 1 is roughly break-even at the conservative end. Year 2+ is net positive at every credible savings level, with effective ROI of 4–25× the subscription fee. We pitch "up to €100/month in peak summer" rather than a flat monthly figure because the literature supports the peak claim cleanly while a year-round average is more defensibly framed as €80–250 annually.

Sources

1. SensorFlow, "Hotels: Guests Are Using A/C All Wrong." sensorflow.co
2. Pang, Z., Chen, Y. et al. (2021), "Quantifying the nationwide HVAC energy savings in large hotels: the role of occupant-centric controls," Journal of Building Performance Simulation 14(6). tandfonline.com
3. US Department of Energy / Pacific Northwest National Laboratory (2012), "Guest Room HVAC Occupancy-Based Control Technology." eere.energy.gov
4. "Long-term field testing of the accuracy and HVAC energy savings potential of occupancy presence sensors in a single-family home," Building and Environment (2024). sciencedirect.com
5. "HVAC energy savings, thermal comfort and air quality for occupant-centric control through a side-by-side experimental study," Applied Energy (2021). sciencedirect.com
6. Halford, M., "Are Airbnb guests less energy efficient than their host?" maxhalford.github.io
7. INSETE (Hellenic Tourism Confederation), "Sustainable Tourism in Greece" (2023). insete.gr
8. International Energy Agency, "Energy Policy Review: Greece 2023." iea.org