As homeowners in Dartmouth and nearby communities look for ways to stretch their budgets further, one area that gets a lot of attention is energy costs. You can reduce how much you spend on utilities by shutting off lights and electronics that aren’t being used, but you shouldn’t overlook the area that takes up the largest proportion of energy consumption. For the average household, heating and cooling account for about 40% of monthly utility costs, so any improvements in your HVAC system’s efficiency can help significantly.

With a little math, you can determine how much energy your AC uses. This does take some time and research, but the information is valuable when you are trying to balance your budget. If you need help or want to reduce the energy that your system uses for heating and cooling, call the experts at Shines Energy.

## Common Measurements for AC Units

Your home AC system is labeled with information from the manufacturer that can help you determine how much energy it uses during an average month. Some of the more common measurements that are listed on the manufacturer labels of AC units are airflow in cubic feet per minute, amount of power in British thermal units (BTU) per hour and electrical current in amps and volts.

## Energy Use and Kilowatts

When you get your utility bill, it details how many kilowatts your household used during the month. The kilowatts are multiplied by a rate that is set by the electric company. If you want to know how many of those kilowatts are used by your cooling system, you need to know how many watts your AC system uses when it runs.

Unfortunately, most AC systems are not labeled with watts, so you need to do some math. Look at the metal label on the exterior unit, and note the number of volts and amps. Amps are listed next to RLA or FLA, and the volts have a V after a number, such as 200/230 V. Use the higher number listed for the volts. Once you have the volts and amps, multiply these two numbers, and you have the number of watts for your AC.

## Check All Components

After you calculate the watts for the main unit outside, check all the other electrical components of your AC system. The condenser, evaporator and fan all use electricity. The label on the outside unit may have all the information you need if you understand the abbreviations. Volts and amps for the compressor motor may be labeled as “Comp. Mot.,” and those for the fan may be labeled as “O.D. Mot.” Follow the same steps by multiplying the amps by the volts to calculate watts. Once you have watts for each component, add the numbers together to get a total number of watts for cooling.

## Average Watts for AC Systems

Sometimes, all you need is a general idea of how much a cooling system costs to operate each month. In these cases, an average number of watts is sufficient. You can estimate how many watts your AC unit uses based on averages for similar models. Central air conditioning uses about 3,500 watts for cooling and 750 watts with the fan only. Small window air conditioners use about 500 watts. Medium to large window air conditioners use 900 to 1,440 watts.

## Why Watts Matter

If you are looking for ways to save money each month, you should pay attention to the number of watts that your AC uses. Once you know the watts, you can then calculate how much money you spend each month just for cooling. If the cost does not fit well within your budget, you can try to use your unit less frequently or decide if it’s time for a new, more energy-efficient AC system. The utility costs that you save each month with a new AC system provide a return on your investment. In other words, the new AC can pay for itself because you spend less on utilities.

## Convert Watts Into Kilowatts

You now have the watts for your AC system from the manufacturer, but your electric bill is in kilowatts. Take the number of watts and divide it by 1,000, and this will give you the number of kilowatts for your AC equipment. The number you calculate reflects the amount of power that the system uses, but it still needs some work before you can use it for energy costs.

## Calculating Energy Use Per Hour

Although the math for energy use per hour based on kilowatts seems complicated, it is actually very easy. The equation requires you to multiply kilowatts of power and the number of hours. Because we are looking for kilowatts per hour, you multiply the number of kilowatts of power times one. You can skip this step and simply use the number of kilowatts of power, but the math is important in case you ever want to calculate more than one hour of use. For example, you might want to figure out how much it costs to run the AC during the day while you’re at work.

## Reading Your Electric Bill

To find the rate for each kilowatt-hour of energy from your bill, look for the detailed breakdown. You should see the total number of kilowatts used multiplied by a number. Multiply this number by the number of kilowatt-hours for your AC system, and you’ll know how much it costs to run your cooling system during the month.

## Ways to Save on Energy Consumption

If your utility costs are too high but you aren’t ready to replace your air conditioning system, speak with a member of our team to find affordable options. We will schedule a time for one of our technicians to come by your home and conduct an energy audit. We may find that you have cracks and openings around doors and windows that make your AC work harder. You may also need to replace or upgrade the insulation to prevent warm air from coming inside. Even a new set of heavy curtains or a ceiling fan can reduce cooling costs.

## Update Your AC System

Many times, Dartmouth homeowners can see savings on utility costs during the summer months by making some easy updates to their cooling systems. A programmable thermostat is a great place to start. You may also want to consider a zone system to distribute cool air into the rooms that you use most rather than cooling your entire home. Shines Energy has many other options for you, so give us a call to learn more.

## Residential AC Experts

Whether you want to know how much your AC costs each month, need to update your cooling system or are ready for an entirely new air conditioner for your home, the professionals at Shines Energy are here to help. We offer heating and cooling installation, repair and maintenance services for families in and around Dartmouth. Call us today to learn more, and be sure to ask about our heat pumps, mini-split systems, indoor air quality products and hot water tanks.