Understanding Energy Efficient Ratios

For most of us, when summer rolls around we want an instant cool down and fast!  Nobody wants to wait around for costly and timely AC installers to squeeze us into their schedule and rob us blind with over priced installation and labor.

That's why most smart people are quickly getting clued into how convenient (and cooling) is it to have a portable air conditioner unit.  A portable air conditioner unit is a room AC that gives you the mobility for instant spot cooling.

But before you go out and by the first one you see, there are a few things you might want to consider, like the EER number.

What's an EER?

EER stands for Energy Efficieny Ratio.  Don't let slippery sales people or technical sites confuse you about how simple this really is.  Simply put, an EER number basically tells you how much cooling an air-conditioner model can provide based on the amount of electrical energy going into it.

The amount of energy going into a unit may be abbreviated as (W).

You may also see EERs listed in a product description as a number followed by (BTU/hr)

•  What is a BTU? 

BTU stands for British Thermal Unit, and it is a measure of thermal heat energy.

Most room air conditioners usually use thousands of BTUs.

•  What is a W?

W is an abbreviation for Watt.  A watt is a standard unit of power. 

You've probably seen the word Watt before when buying light bulbs. 

For electrical power, one watt is equal to one ampere of current per second.

How do BTUs and Ws help us understand EERs?

To figure out an EER, we have to look at both the BTUs and the Ws of a unit.   The way to do this is to divide the number of BTUs to the number of watts. 

If you compare two air conditioner units with the same BTU's, you can still figure out which one is more energy efficient if you divide each BTU by the number of Watts each unit uses.

Example Scenario

For example, lets say that you're shopping online and you find two great AC units, unit A and unit B.  Now let's say you do a comparison of the two and find that both A and B have a BTU of 10,000.

What you should then do is look at each unit's listed Watt (W).  Let's say that unit A has 1,200 W and that unit B has 1,000 W.

To find the EER for unit A, divide 10,000 BTUs by 1,200 W.  This gives you an answer of 8.3.   Your EER for unit A is 8.3.

Follow the same formula to find the EER for unit B.  Divide 10,000 BTUs by 1000.  This gives you an EER of 10. 

Now you have two choices:  unit A with a EER of 8.3 or unit B with an EER of 10.

Which EER is better?

The higher EER is always better.  If you go with unit B, you'll have a more energy efficient system.

The national appliance standard requires all room air conditioners to have a minimum EER of 8.

Keep in mind that the higher the EER, the more energy efficient the air conditioner is.  An EER of 12 and above is considered good, and an EER of 13 and above is outstanding.  And just remember that units with higher EERs will be more costly than their lower EEER counterparts.

Is the more expensive EER unit wallet-friendly?

Since portable air conditioners with the higher EER are more expensive, the next question you want to ask yourself before you make a final decision is:  Which unit is a better investment over time?

Let's assume the price difference between unit A and unit B is $100.  A hundred dollars may seem like a lot but is it really if you take into consideration how much energy the better unit will be saving you in the long run?  Remember that less energy used means a lower electricity bill, and a lower electricity bill means less money coming out of your wallet every month.

The unit with the better EER may seem like an expensive buy, but it is actually a money saving investment that will keep you cool and fresh throughout hot muggy and dry summers.

Making the right choice

If you can afford it, perhaps by making small cuts elsewhere, it is best to get a portable room air conditioner unit with a higher EER.  If this is your move, then you may want to consider the Amcor AL1000E, pictured on the left.  It has a number of fantastic features, one of which is an EER rating of 16.66.

Either way, knowing your terminology before hand makes the process of choosing the right portable air conditioner much easier!

When shopping online, take advantage of the ready made comparison charts many online vendors offer.  This way you can quickly gauge air conditioner EER figures and pick the one best for you and your family.