Portable Air Conditioners and Energy Efficiency

In the stifling summer heat, portable air conditioners can take the edge off of a hot room, as they are great for supplementing or substituting for central air conditioners. Because they are usually compact and fully mobile, portable air conditioners can be the perfect cooling solution for any room in your home, office, work site, or even a computer server room due to the fact that they are fully portable and require no permanent installation.

Unlike window air conditioners which pull air from the outside to cool a room, portable air conditioners actually use indoor air by dehumidifying this air and collecting the condensate into a either a bucket or by evaporating it and exhausting it through an included exhaust hose.

Although this entire process may seem easy enough, when choosing a portable air conditioner, there are two very important factors to consider: BTU's and EER. BTU's stand for British Thermal Units, which measures how much heat is removed in an hour. On the other hand, EER stands for Energy Efficiency Ratio, and is basically a measure of how energy efficient an air conditioner is at a specific level - usually 95 degrees Fahrenheit. Therefore, if you're concerned with energy costs, a portable air conditioner's EER rating is absolutely crucial in determining whether the unit you're buying is an energy saver or energy guzzler.

Calculating a portable air conditioner's EER involves a basic formula: it's simply the ratio of BTU's the unit produces to the power input of the unit in watts, and the higher the EER, the more energy efficient the unit will be. For example, a portable air conditioner producing 10,000 BTUs that uses 1,200 watts has an EER of 8.3. This can be calculated as such:

The following example is one of another air conditioner with 10,000 BTU's that uses 1,000 watts:

As such, the unit with the higher EER of 10 can produce the same amount of cooling but more energy efficiently, and to save money, it's best to choose the unit with the higher EER. However, generally speaking, a unit with a higher EER rating is usually accompanied by a higher price tag. Also, it should be noted that national appliance standards currently require room air conditioners to have a minimum energy efficiency ratio of at least 8.

In terms of price difference and energy savings over time, you can find out this information by performing a few more simple calculations. Assume that the price difference between the above two units is $100. To find out the energy savings the more expensive unit will offer, keep in mind two factors:

1. The approximate number of hours the portable air conditioner will be operating
2. The amount a kilowatt-hour (kWh) costs in your particular area

Assume you plan on using the portable air conditioner for four months out of the year, six hours per day, and a kilowatt-hour costs $0.10. The difference in price between the two is $100 and the difference in energy consumption is 200 watts, meaning that for every five hours, the less expensive unit will consume will one additional kWh and $.10 more than the more expensive unit.

With that in mind, if it's within your budget, try to find a portable air conditioner with a higher EER, such as the Amcor AL10000E, which boasts an EER of 16.6. This is especially important if you will be operating the unit for extended periods of time and wish to prolong the life of your portable air conditioner.

See Portable Air Conditioners

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