Temperature setback lowers indoor temperature when a building is empty. Ento compares how you heat today with a realistic weekend and holiday schedule, then shows the extra gas you could save.
Stop heating empty buildings: how temperature setback potential works
Many buildings heat as if they were occupied all week. Classrooms sit at comfort temperature on Sunday. Town halls stay warm through Christmas. Offices cool only a little overnight, then spend the weekend as if Monday had already started.
That is wasted gas. Temperature setback is the practice of lowering the indoor temperature when nobody is there, then bringing it back before people return. It is one of the simplest heating savings you can make — if you know which buildings are already doing it, and which ones are not.
Ento’s temperature setback potential answers that question from the gas meter. It does not wait for a complaint, and it is not an alarm. It is an energy-efficiency estimate: how much more you could save if the building followed the weekend and holiday setback you actually intend.
What temperature setback is — and what it is not
Setback is not turning the heating off. It is running the building cooler while it is empty, then recovering in time for occupancy.
A school can often drop several degrees from Friday evening to Monday morning. A care home cannot. An office might set back on Saturday and Sunday. A sports hall might already do that on weekdays after closing, but still heat through the holidays.
The right setback depends on the building. The missed opportunity is the same: heating an empty room as if someone were sitting in it.
Setback is also not the same as a fault. A building that never sets back on weekends is usually following its schedule, not breaking down. That is why this analysis shows up as a potential — a saving you can choose to take — rather than an alert that something has gone wrong.
How Ento sees it in the data
You do not need indoor sensors for this. Ento uses the gas meter and outdoor temperature.
First it learns how the building heats in cold weather: the heat profile. That is the familiar relationship between outdoor temperature and gas use. A leakier or more heavily heated building uses more gas for the same outdoor temperature.
Then it asks a second question: does gas use drop when the building should be empty?
If Saturday and Sunday use about as much gas as a typical weekday, the building is probably staying near comfort. If they run clearly lower, a setback is already in place. Ento looks at the same idea for holiday periods — Christmas and winter vacation — when occupancy often falls even further.
In the product you will see this as Present versus Optimal:
- Present is what the building is doing now, inferred from metered consumption. If there is no weekend setback, Present is effectively “comfort all week”.
- Optimal is the setback you intend: which days, how far to lower the temperature, and how long holidays should run cooler.
The potential is the difference. If the building already sets back to your intended schedule, the extra saving is small. If it barely sets back at all, the potential is the heating you are still putting into empty rooms.
Savings are shown as energy and cost per year, based on applying both the intended weekend setback and the intended holiday setback.
Why the estimate is conservative on purpose
A thermostat can be told “15 °C” at 16:00 on Friday. The rooms will not be 15 °C at 16:01.
Heavy buildings cool slowly. Light buildings cool faster. If Ento assumed the indoor temperature jumped to the setback the moment the schedule changed, it would overstate the saving. So the model ramps the room temperature down and back up, instead of treating the setpoint as the actual indoor temperature.
That is the ramp rate: how quickly the building loses and regains heat. A slower building keeps more of the comfort temperature at both ends of the setback, so it saves less. You can adjust this if you know the building is particularly heavy or light.
Ento also scores setback during the heating season. Summer gas use is not treated as a missed weekend setback.
The result is not a theoretical maximum. It is an estimate of what you would save if the building actually followed the schedule you set, in the weather you have already seen.
Weekends and holidays are different opportunities
Weekend setback is the recurring one: Friday, Saturday, Sunday, or a combination. The default intention is Saturday and Sunday. Friday is included when that matches how the building is used, or when you choose it.
Holiday setback is the longer one. Empty schools in week 7, closed offices between Christmas and New Year, and similar periods often dwarf a single weekend. Ento looks at:
- Christmas, from 20 December
- Winter vacation, from the school calendar where available
You can set a different setback temperature and number of days for each. A school that already cools on weekends may still heat through the entire Christmas window. That is a separate, often larger, opportunity.
The cards in Ento split these so you can see both: weekend consumption versus a typical day, and holiday consumption versus a typical day — Present, Optimal, and the saving in between.
You set the intention. Ento measures the gap.
A nursing home, a day-care centre, and an administration building should not share the same target.
On the potential you can set:
- Comfort temperature
- Weekend setback temperature and days
- Christmas and winter-vacation setback temperature and length
- How fast the building is allowed to cool and recover
Those values are the Optimal schedule. Present stays grounded in the meter. Recalculate after you edit, and the next advisor run will use the new parameters.
That is the point of the analysis. Ento is not imposing a 15 °C weekend on every site. It is showing how far current heating is from the setback you consider acceptable for that building.