Pre-cooling for air-conditioners
Pre cooling an air conditioner has tangible, quantifiable economic benefits – it saves energy, water and money.
An air conditioner uses energy to produce cool, dehumidified air. The amount of energy used is related to the ambient temperature – the hotter it is, the more energy is consumed to run the condenser. The figure commonly used is 2 – 2.5% for each 10C rise in ambient temperature. HVAC consumes 20-25% more energy at 380C than it does at 280C
On a 380C day, if the air being used by the HVAC unit can be cool to 280C before entering the condenser, then your electricity bill will reduce by 20-25% to run the HVAC
How? - Use a high-pressure pre-cooling misting system on the HVAC. The figure of up to 30% savings on HVAC power bills are common when pre-cooling misting is installed. The payback period can be less than one summer.
Pre-cooling misting consists of installing misting heads near the air inlet for the condenser. The pump monitors the energy consumption of the condenser. When the condenser switches on, so does the misting pump. A temperature monitor can be added to the misting system which prevent the misters working until a trigger temperature is reach, as a result, the misters do not work in cooler conditions (winter).
Environment considerations:
It is estimated by IEEE (Institute of Electrical and Electronics Engineers) that 95 Litres of water is required for each 1 kilowatt hour of electricity generated. This means to run an air conditioner for 1 hour would indirectly consume 95 litres for each 1kWh consumption of the condenser. A 10kWh system is consuming 950 litres/hour. A pre cooling misting system uses about 3-5 nozzles per condenser, consuming .075-0.1lts/min or about 4.5-6 litres per hour.
Using a pre-cooling misting system on a 10kWh HVAC saves about 25-30% on energy, around 250 litres per hour on water plus the cost of electricity. The water usage and power required for the misting system is negligible.
How is a pre cooling system fitted?
The misting heads are located externally to the coils. This means they can be retrofitted as easily as fitting at the time of installation – it makes no difference. These are simple installations as a rule and therefore not particularly expensive.
Advantages of high pressure misting
- Relatively low cost (especially compared with HVAC)
- Sizable power savings – up to 30%
- Reduces ambient temperature entering the condenser by 100C to 150C
- Increase efficiency of the HVAC system, up to 30%
- High pressure results in little or no wetting of condenser coil = low maintenance
- The misting system is low maintenance
To find out more, call us on 0490 466 161 or 0466 548 956 or email us at info@mistify.com.au