The Coolzy.com Coolzy-Pro and Coolzy-Go units run on AC 240 Volt 50 Hertz power supply, which is the standard Australian residential power supply.
A Coolzy is one of the lowest power air conditioners on the market which makes it particularly suitable for off-grid applications.
If you are unfamiliar with off-grid power solutions, there is a technical note with some explanations so you can understand the technology. Here’s another page providing our inventor’s recent experience using his Coolzy off-grid.
If you plan to operate your personal air conditioner away from normal AC power supplies, for example, on batteries, solar panels, or a generator, this page provides suggestions.
Please note that our product warranty covers normal use on specified power supplies. It is your responsibility to ensure that your power supply conforms with the product specification requirements with a minimum supply voltage of 215 Volts AC and a maximum of 250 Volts AC. Running the AC outside this voltage range can damage the compressor and other motors.
We recommend that you thoroughly test any alternative power supply before departure from your home base.
Coolzy doesn’t just reduce your cooling bills, our solutions have also been engineered to also dramatically reduce CO2 emissions compared to standard air conditioners, which can be one of the worst contributors to carbon emissions.
The warm air generated out of the back of the machine, was barely noticeable and vented from the room via an open window.
Coolzy.com air conditioners can run from small 240 Volt AC generators.
Choosing a generator is very similar to choosing an inverter as stated below.
The generator should have a rated peak load of 1.8KW or higher, and a constant load of 350W or higher.
Most generators can run more than one Coolzy unit at the same time.
If you plan to use your Coolzy at a caravan park or organized campsite, be aware that generators can usually only be used during restricted hours. Generators are almost certainly not permitted between around 8 pm and 8 am while most people are sleeping or resting. That is why a storage battery is essential for most organized campsites or caravan parks that do not provide grid power.
Multiple Coolzy units being powered by a single generator during product testing.
A typical off-grid power system consists of a series of solar panels, an electronic inverter to convert DC solar power to AC power for household appliances, and a storage battery to provide power when there is insufficient solar power.
If you plan to use a Coolzy in a solar powered house (usually 3.2Kw or more), then just plug it in and use it just like any other appliance.
For car or caravan solar panel, the user will need a suitable solar inverter in order to use a Coolzy. The solar inverter should be able to charge your battery as well as run the appliance. An electronic switch can automatically charge your storage battery when excess power is available from your car alternator, also from a solar panel mounted on the roof or nearby.
In common with refrigerators, a Coolzy draws a very short burst of high current to start the compressor, around 5 – 7 Amps. The normal operating current is about 1.3 Amps.
You should choose an inverter with a peak (starting) load rating of at least 1800W (2100W is recommended), and a steady load rating of at least 350W. The peak load will only last for 5 – 15 milliseconds at the time of starting the compressor each time.
You should account for the load of all your other appliances that could possibly be drawing power from the inverter at the same time, then add that to the constant load.
We recommend that you test a Coolzy unit on your preferred inverter product first before purchasing, along with the other appliances such as a car fridge..
Make sure the unit is in cooling mode. The ambient temperature must be at least 20 °C. Run your Coolzy on the inverter for at least 10 minutes, switch off the Coolzy, then switch it on again, and test for a further 5 minutes.
The Coolzy-Pro can operate on both a pure sine-wave inverter and a modified sine-wave inverter. A sine-wave inverter is usually more expensive but has a higher efficiency (85%- 95%),. A modified sine-wave inverter can be more common and affordable but it has a lower efficiency (60%-85%). Also a modified sine-wave inverter may cause some additional buzzing noise to come from your Coolzy. This is not harmful, but can be annoying.
12 Volt sine-wave inverter that converts 12 Volt DC (Direct Current) from a battery (red and black cables) into 230 Volts AC power for Coolzy (white cable). This model has 1500 Watts capacity and also can be used to charge the battery when AC power is available.
The unit is approximately 40 cm x 30 cm x 12 cm and weighs about 12 kg. More modern inverters avoid using a low frequency transformer which makes up most of the weight and are therefore much lighter.
A typical off-grid power system consists of a series of solar panels, an electronic inverter to convert DC solar power to AC power for household appliances, and a storage battery to provide power when there is insufficient solar power. A small generator can also be used to charge the storage battery.
Special switches are available to enable your vehicle alternator to charge your storage battery while driving. The switch protects the starter battery, ensuring the the alternator charges the starter battery first before charging your storage battery.
There are many different types of rechargeable battery that you can use with an inverter.
Standard lead-acid car batteries will work, but you can only draw about 40% of the battery capacity. Therefore it is better to purchase “deep cycle” batteries.
Today, the best battery option in terms of weight, durability and life cycle cost is a lithium ion battery.
Make sure the battery voltage matches the inverter input voltage.
A single lithium-ion battery sufficient to run Coolzy on maximum power for a night will weigh 20 – 30 kg. Therefore, it is more convenient to wire two or three smaller batteries in parallel. When wired in parallel, the batteries must all be the same type with the same battery management electronics (if included).Otherwise, charging and discharging will be uneven and may damage the batteries.
A lead-acid battery with sufficient capacity to run Coolzy all night will weigh 70 – 100 kg.
We assume the following:
Using 12V system.
Coolzy-Pro operation hours: 7 hours
Inverter efficiency: 85% (Good quality modified sine wave inverter)
Depth of discharge: 95% (Lithium deep-cycle battery)
Constant power demand = 340W.
With a 12V battery, the current will be 340 / 12V = 29 Amp (Make sure the battery cables you use can carry 30 Amps constant current).
Transient peak power demand is about 1800W for 5-15 milliseconds.
1800 / 12V = 150 Amp ( Make sure your battery has a CCA rating equal or higher than 150 Amp)
The battery size can be roughly estimated with the following equation:
(duration x steady battery current) / (depth of discharge * inverter efficiency)
Based on the above figures, the equation gives:
(7 hours x 29 Amp ) / ( 0.95 depth discharge x 0.85 inverter efficiency ) = 250 Amp-hours
This is the smallest battery size it requires to run the AC for 7 hours. Please note that the Coolzy when used with the Igloo tent has the potential to extend the operation time by about 30% under certain and remote control settings. Further, if the return air temperature drops below the thermostat temperature setting, the compressor will stop for a couple of minutes, reducing the average power consumption.
Please also allow sufficient extra capacity for other appliances that could possibly consuming power at the same time. If you are uncertain about the steady current being supplied by the battery, install a current shunt as explained in the next section.
Three 12 Volt lithium-ion batteries, each with 100 Amp-hour capacity, wired in parallel and connected to an inverter.
The battery may be supplying 30 – 50 Amps of power to your Coolzy, a fridge and maybe some other appliances. You need thick battery cables to carry the current without a significant voltage drop and power loss. This makes it impractical to measure the current directly.
Instead, we can measure the current indirectly. A current-shunt consists of a series of metal rods in parallel with precisely known resistance, around 0.0001 Ohm. When current flows through the rods, we can measure the small voltage needed to do that, around 1 millivolt. An amplifier at the current-shunt sends the current reading and battery voltage to a small meter. Advanced models incorporate a micro-computer that calculates the battery charge for you.
A current-shunt will cost between $100 and $200, but will give you peace of mind knowing the state of your battery charge. When you need to store your batteries for a long time, a current shunt will help you ensure that they retain around 40% of their full charge, and thus ensure the longest possible storage life.
Current shunt installed on an inverter to measure the DC current drawn from the battery (or being added to the battery during charging). The current meter can be mounted some distance from the current-shunt if needed.
