Heating and cooling
Heating, ventilation and air conditioning (HVAC) equipment generally accounts for about one third of the energy used by commercial buildings.
Improving the efficiency of your HVAC system can offer some of the most significant and lowest cost energy savings.
The basic energy saving principles for HVAC systems are:
- Only cool or heat as much as necessary
- Only cool or heat for as long as necessary
- Don’t heat and cool the same space at the same time (this occurs in about a third of New Zealand buildings)
- Only use heating and air conditioning if the windows and doors to the outside are shut.
If some staff have personal heaters under their desk, even though there is an office heating system, then the system is not working properly.
Low-cost or no-cost actions
- Set your heating and cooling system’s timers for business hours only
- Set the air conditioner to turn off at least one hour before the end of the working day
- Regularly maintain your air conditioning system - this can save up to 25% of the cost of once a year maintenance
- Have a building services engineer optimise the controls for you HVAC system, at least annually, inlcuding looking at the set points
- Have a wide band for set points, so that your equipment is not working too hard. Four degrees (for example 20 – 24oC) is generally found to be comfortable
- Make sure thermostats are correctly calibrated and not located in unusually hot or cold areas
- Set your air conditioning humidity control so it floats between 30% and 60% relative humidity.
Heat pumps
An increasing number of small businesses are using heat pumps during winter. Check out what to look for when buying a heat pump.
