--- title: "OccuSense hotel simulation in 3D | GridBit" description: "A simulated hotel in 3D on a 41 °C summer day: one room, one floor and 126 rooms, first without OccuSense, then with it, and the energy saved." url: "https://www.gridbit.tech/solutions/occusense/simulation" language: "en" translation: "https://www.gridbit.tech/bg/solutions/occusense/simulation" --- # OccuSense simulation: one day in a hotel The simulation follows a hotel with 126 rooms on the Aegean coast through a July day of 41 °C: first one room, then one floor, then the whole hotel, each time as it works today and then with GridBit OccuSense. The hotel, the guests and every value are simulated. ## Without OccuSense, the room cools nobody 09:40. Outside it is already 35 °C. The guests of room 407 set the unit to 18 °C and go to the beach for the day. They leave a second card in the holder by the door, as many guests do, to come back to a cool room. In this heat the unit works ever harder to hold 18 °C and runs at full power in the afternoon, and a lamp stays on. By 16:40 the two use 9.3 kWh for nobody. ## The same day with OccuSense Three devices go in without new cables. The sensor on the ceiling sees whether anyone is in the room, the actuator next to the indoor unit gives its commands by infrared and checks them by the current, and the gateway in the corridor decides for every room on the floor. ## Eco first, then off The card is still in the holder, but the sensor sees nobody. After 15 minutes the gateway puts the room in eco, 27 °C, and switches the lamp off; the current clamp confirms that the unit has dropped to standby. If nobody comes back within half an hour, the gateway switches the unit off. The owner sets the times and the eco temperature. ## The room is ready when they come back OccuSense has learned that the couple come back from the beach at about 16:40: on the two days before they came back at 16:34 and 16:46. It also knows how long the room takes to cool after a day in this heat with the unit off, so the gateway starts the unit at 13:50 instead of half an hour before they return, as on a mild day. At 16:40 they walk into a room at 21 °C. While they were out the room used 4.8 kWh instead of 9.3 kWh. ## One floor at dinner time 20:30 on the fourth floor. The PMS shows all 18 rooms occupied, the sensors find people in 3. Without OccuSense the units run in 11 empty rooms. With it those rooms are in eco and switch off after half an hour, and the floor plan shows the state of every room. ## The gateway decides, even without internet 22:02. The hotel loses its internet connection. The floor gateway goes on deciding for its 18 rooms: the guests of room 403 come back at 22:12 and their room goes to comfort, room 411 empties and goes to eco at 22:18. The cloud only collects the data, so it marks the floor as offline and nothing else changes. ## The guests sleep, the air conditioning stays on 00:40. Nobody in room 407 has moved since 23:58. A plain motion sensor would have switched the unit off on the sleeping couple at 00:28. OccuSense sees them breathe with its radar, and the CO₂ in the room confirms it, so the room stays in comfort. On this floor a motion sensor alone would have stopped the units of sleeping guests 103 times during the night, for 45 hours in all. ## The whole hotel, the next morning 10:40. The PMS has 107 rooms occupied, and people are in 25 of them: the rest are at breakfast, at the beach or checking out. Without OccuSense the units run in 52 empty rooms. With it the 77 rooms whose guests are out are in eco or off, and so are the rooms the PMS shows as free or checked out. ## The day and the month in euros, on one screen Every floor gateway sends the data of its rooms to the GridBit platform. The manager sees the saving of the day and of the month in euros, the rooms in use against the PMS and what needs attention. The same data build the evidence for the EPBD: how the building automation works and the air quality in the rooms. ## A day, a week and a month in numbers - **24 hours**: €85 - **7 days**: €648 - **30 days**: €2,815 From 13:00 to 13:00 the hotel used 2,096 kWh for air conditioning and lights without OccuSense and 1,670 kWh with it, 20% less. The week and the month have the same heat and new guests every day; over 30 days the CO₂ emissions fall by 5.6 t. With eco alone the saving would have been 12%. Every number is simulated; a pilot measures them in your building. How the simulation works ## A simulated hotel, a real sun The sun follows its real path over the Aegean coast on 15 July and heats the west rooms in the afternoon, and the air outside goes from 27 °C at dawn to 41 °C. Every room is a small thermal model: the outside air, the sun on the glass, the guests and the lights warm it, and an inverter split unit cools it. The guests come and go by their own day: breakfast, the beach, dinner, sleep, arrivals and departures. Most of them spend six or seven hours at the beach or on a trip. For the week and the month the same model runs the 30 days that end with the day of the story, all as hot, with guests who arrive and leave as in any week of the season. Without OccuSense the rooms have key card holders. In the simulation the guests set the unit to 18 to 23 °C, more than half of them leave a second card in the holder when they go out, some leave the balcony door open, a card left at check-out stays until housekeeping comes, and housekeeping switches the unit on in some rooms they prepare for the next guest. With OccuSense the example rule applies: comfort at the temperature the guest chose while someone is in; after 15 minutes without anyone, eco at 27 °C for half an hour and then off; off as soon as the card is taken out; off for rooms the PMS shows as free or checked out. The floor gateway learns when each guest usually comes back and starts the unit in time to bring the room within 3 degrees of their temperature: half an hour before on a mild day, earlier after a day in the heat with the unit off. In free mode the same hotel can also stand on the Black Sea in July (19 to 31 °C) or in a ski resort in January (-18 to -6 °C). There the split units heat, the guests ask for 23 to 27 °C and spend the day on the slopes, and a room with its unit off is kept at 12 °C so that it does not freeze. The panel of the whole hotel sums the last 7 and 30 days for the place and the rules you choose. [Back to GridBit OccuSense](https://www.gridbit.tech/solutions/occusense) - **Hotel**: 126 rooms on 7 floors, split units - **Day**: 15 July, 27 to 41 °C outside - **Week and month**: the 7 and 30 days up to that day, in the same heat - **Guests**: 18 to 23 °C, 6 in 10 leave a card - **Empty room**: eco 27 °C after 15 min, off 30 min later - **Return**: room ready when the guest usually comes back - **Lights**: off in an empty room - **Other places**: Black Sea in July, mountains in January - **Price of electricity**: 0.20 € per kWh - **Emission factor**: 0.40 kg CO₂ per kWh Questions ## Short answers Another question? [Ask an engineer](https://www.gridbit.tech/contact) ### What happens when the hotel loses its internet connection? The rooms go on as before. OccuSense takes every decision in the floor gateway, so the rooms switch between comfort and eco without the internet. The cloud collects the data for the platform and for reports such as the EPBD evidence. ### How does OccuSense know that a guest is asleep and not gone? The ceiling sensor combines a passive infrared element, a millimetre-wave radar and a CO₂ sensor. The radar picks up movements as small as breathing and the CO₂ confirms that someone is in the room, so the air conditioning stays on while the guests sleep. A plain motion sensor sees no movement and switches it off. ### Does OccuSense work with key card holders? Yes. Where a room has a holder, OccuSense reads the card: a card taken out switches the room off, as the holder does. A card left in the holder does not keep an empty room running, because the sensor sees that nobody is in, and the room goes to eco and, if nobody comes back, off. Rooms without a holder work by presence alone. ### Should an empty room go to eco or switch off? OccuSense can do both, as the owner sets it: eco for the first half hour, in case the guest comes back soon, and then off. Eco alone keeps the room ready but saves less; switching off at once saves the most. In the simulation of a 41 °C day eco alone saves 12%, and eco followed by off, with the returns learned, 20%. ### How does OccuSense know when a guest will come back? It learns it from the ceiling sensor. When a guest has come back from their day out at about the same time on the previous days, the floor gateway starts the unit in time for that return: half an hour before on a mild day, earlier after a hot day with the unit off. If the guest does not come, the unit goes off again. ### Can OccuSense switch the lights and other devices in the room? Yes, depending on the installation. Besides the air conditioning OccuSense can switch the lighting and other electrical devices in the room, and the owner decides what goes off when the room is empty. ### Are the numbers in the simulation measured? No. The hotel, the guests and every value are simulated to show how the system works. The pilot on one floor replaces them with numbers measured in your building, against the target of 15 % or more off the HVAC consumption. ## Request a pilot Tell us about the hotel: rooms, floors, the type of air conditioning and whether you use a PMS. We answer with a plan for the survey. [Request a quote](https://www.gridbit.tech/contact?product=GridBit%20OccuSense) [sales@gridbit.tech](mailto:sales@gridbit.tech)