LowCarbonComfort : Heating and air conditioning energy saving using adaptive comfort theory and temperatures, free and pre cooling natural ventilation strategies

Adaptive Comfort Temperatures

Savings of up to 20% heating and cooling energy can be achieved by using adaptive comfort temperatures in buildings. Comfort can also be improved.

Adaptive comfort temperatures vary in harmony with outside temperature. The variation is based on the principle that people naturally adapt to suit prevailing climate conditions (via dress, window opening, etc).

Heating may typically be set at up to 2°C below the adaptive comfort temperatures shown on the map in winter, cooling up to 2°C above in summer.

Find out more about Adaptive Comfort Temperatures

Pre Cooling

Savings of up to 50% cooling energy can be achieved by opening windows early in the day and preceding night to pre cool buildings. Peak summer temperatures can also be reduced in buildings with heating only.

The cooling introduced early on is stored in the building fabric then released later in the day when it is needed.

Predictive strategies for various locations are shown on the map to provide guidance on when to pre cool. Strategy modes are defined as follows:

Minimize ventilation "stop" - Outside too hot, too humid or too cold.

Free cool "continue" - Ventilate to maintain comfort.

Pre cool "go" - Ventilate to store cooling in building fabric.

Off - Out of hours (and no requirement to pre cool).

Find out more about Pre Cooling Strategies

00/00/0000 00:00

Last updated: 01/09/2016 19:30 (GMT)

Notes

Savings values are for moderate climates similar to UK.
The adaptive comfort temperatures shown on the map are for free running buildings with mainly sedentary (sitting based) activities. These are buildings where the occupant has control over themselves (eg dress) and their environment (eg window opening) - ie they have adaptive opportunity. Find out more about Adaptive Comfort Temperatures
Temperature set-points should be subject to other considerations including local regulations, standards and guidance, other requirement criteria such as for equipment or artefacts, maintaining a dead band between heating and cooling systems so as to avoid conflict and energy wastage, localized thermal effects such as radiant cooling / heating close to building facades, etc
A comfort band for temperature variations of +/-2°C around the comfort temperature would generally be considered acceptable. Adopting a tighter band would reduce savings while a looser band would increase savings.
Window opening or opening of similar ventilation devices should be subject to other considerations including security, safety, noise, pollution, adverse weather, local discomfort, overcooling bringing on heating, fresh air requirements, etc.
The predictive pre cooling strategies shown on the map are for free running buildings with moderate heat gains where the adaptive comfort temperatures are maintained by air conditioning. Strategies for other heat gain levels and buildings with heating only are provided on the Data pages.
For the purposes of this website the term "air conditioning" is considered to include mechanical cooling and comfort cooling.