air conditionerEach air conditioner has an energy-efficiency rating that specifies how many BTUs per hour are used for every watt of power it takes. For room air conditioners, this rating is the Energy Efficiency Ratio, or EER. For central air conditioners, it is the Seasonal Energy Efficiency Ratio, or SEER. These ratings are placed on an Energy Guide Label, which must be affixed in a noticeable place on all new air conditioners. Many air conditioner manufacturers are voluntary participants in the EnergyStar ® labeling program. EnergyStar-labeled appliances mean that they have high EER and SEER ratings.

Relationship Of EER Rating And Your Air Conditioner

How is EER Computed?

The EER of an air conditioner is its British thermal units (BTU) rating over its wattage. For instance, if a 10,000-BTU air conditioner consumes 1,200 watts, its EER is 8.3 (10,000 BTU/1,200 watts). The greater the EER is, the more efficient the air conditioning unit is. Nevertheless, normally a greater EER is accompanied by a higher price.

Would the Higher Portable Air Conditioner EER Rating be Worth the Extra Cost?

Let’s say that you are presented a choice when comparing two 10,000-BTU air conditioning units. One has an EER of 8.3 and consumes 1,200 watts, and the other has an EER of 10 and uses 1,000 watts. Let’s also say that the price deviation is $100. To compute what the repayment period is on the more costly unit, you must know:

1. About how many hours per year the unit will be operating.
2. What the rate of a kilowatt-hour (kWh) is in your area.

Let’s say that you decide to use the air conditioner in the summer (approximately five months a year, depending upon where you live) and it will be running about 8 hours a day. Let’s also say that the cost of a kilowatt-hour in your area is roughly $0.10. The variation in energy consumption between both units is 200 watts, which suggests that every five hours the less expensive unit will consume 1 additional kWh (and therefore $0.10 more) than the more costly unit.

Supposing that there are 30 days in a month, you find that during the summer you are operating the air conditioner:

5 mo. x 30 days/mo. x 8 hr/day = 1200 hours.
[( 1200 hrs x 200 watts) / (1000 watts/kW)] x $0.10 / kWh = $24.00.

Since the more costly unit costs approximately $100 more, this implies that it will take around 4 years for the more expensive unit to recover cost.

Buyer Beware!

Not all BTU ratings could be trusted. Simply because the BTU’s are stated as being high on specific air conditioning units, it does not mean it is always true. Some producers will overestimate the BTU’s on units to increase the opportunity of selling them and others will be more conservative in relation to the BTUs, which will cause the EER rating to be lower so a lower portable air conditioner EER may be misleading. It is ideal not to allow the EER energy rating as being your only criteria for picking an air conditioning unit.

For Inquiries About EER Rating, Ask Your Air Conditioning Company

Do the investigation on whatever unit you are thinking about for your home and you will be more pleased with your purchase.

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