Energy efficiency is always an important consideration when installing any new appliance in your home, and it is especially important when installing a new AC unit since it will use much more energy than any of your other appliances. The energy efficiency of an AC unit is expressed in its SEER rating. SEER stands for Seasonal Energy Performance Ratio and is a way to estimate how much energy a unit would use per year and thus how much it would cost to operate. All new AC units are required to have a certain SEER rating and meet specific energy efficiency requirements, and today we’re going to look at what these SEER standards are in California and also discuss what SEER ratings really mean.

Minimum Energy Efficiency Standards for New Cooling Units in California

In the US, federal laws always supersede any state laws. This means that the federal government, specifically the US Department of Energy (DoE), is the one that sets out the minimum energy-efficiency requirements for air conditioners and other HVAC units. These requirements vary in different regions of the country due to the differences in climate.

When setting minimum energy efficiency standards for air conditioners and other cooling units like air-source heat pumps, the DoE separates the country into three regions: north, southwest and southeast. California is in the southwestern region, and the requirement for any new cooling unit installed in this region is that it must be at least 15 SEER. This is a new requirement that went into effect at the start of 2023 as the previous law was that all new cooling units in the southwestern region had to be at least 14 SEER. Compared to the previous 14 SEER standard, the new 15 SEER standard equates to an approximately 7% increase in energy efficiency.

If you’re considering installing a heat pump instead of a traditional central AC unit, the heat pump will also need to meet a certain requirement in terms of minimum heating energy efficiency. The heating efficiency of air-source electric heat pumps is measured using a metric known as Heating Seasonal Performance Factor (HSPF). The minimum HSPF requirement also increased at the start of 2023 so that any new heat pump must now have a rating of at least 8.8 HSPF. Unlike the minimum SEER ratings, the minimum HSPF requirement is the same for all three regions of the country.

What Do SEER Ratings Really Mean?

SEER ratings are simply an expression of how many BTUs of heat an air conditioner can remove from the air over one hour or any specific length of time compared to how many total watts of electricity the unit will consume during the same time period. The higher the unit’s SEER rating is, the more efficient it is and the less energy it will use to cool your home.

The total number of BTUs of heat an AC unit can remove in one hour is determined solely by the size of the unit. For instance, any 2-ton AC unit will be capable of removing 24,000 BTUs of heat energy from your home in one hour if it were to run non-stop for the entire hour. However, some ACs will use more electricity to remove the same amount of heat energy than others and thus not be as energy efficient.

Calculating the actual energy efficiency of any air conditioning unit can be tough, and this is because the effectiveness of an AC unit can vary quite drastically depending on how hot and humid it is outside. Finding the energy efficiency of window air conditioners is relatively easy since these operate in a controlled environment inside your home, which means the amount of heat they remove and the amount of energy they use to do so always remain about the same. This isn’t the case for central air conditioning since the main part of the system sits outside and is directly affected by the outdoor temperature and humidity.

The energy efficiency of window ACs is measured using a metric known as the Energy Efficiency Ratio (EER), which just looks at BTUs of heat removed compared to watts of electricity used in one hour. Since central ACs are directly impacted by outdoor heat and humidity, the only way to accurately measure energy efficiency is to measure the amount of energy consumed in one hour in varying weather conditions and then average this out throughout the entire cooling season from late spring to early fall.

Before the SEER rating can be calculated, the unit must first be tested to see how much energy it consumes per hour under the different conditions it would normally operate in during a typical cooling season. This means running the unit in varying humidity levels and in temperatures between 60 and 100 degrees to see how effectively it cools and how much energy it uses in each of these different conditions. This then allows the researchers to determine the average hourly energy usage across the entire cooling season. Once this has been determined, the SEER rating can then be calculated by dividing the number of BTUs of heat the unit can remove by the average number of watt-hours of electricity it uses across the cooling season.

How to Know What SEER Rating Is Best for Your AC?

Choosing the right SEER rating for your new AC unit or heat pump is really a matter of personal choice as there is definitely nothing wrong in going with a more basic 15 SEER unit. However, it also depends on how much you’re willing to pay to cool your home since a 15 SEER unit will always use more electricity than a unit with a higher SEER rating.

If you have a set budget for your new AC, you’ll obviously want to use this as your starting factor and then determine what types of units are available within your price range. From there, it helps to then estimate approximately how much energy you could save with a higher SEER unit per year and over the average life of the unit compared to a 15 SEER unit. Calculating the estimated lifetime savings is especially important for determining whether or not the higher SEER unit is worth the increased price. Let’s say that you’re considering an 18 SEER unit that costs $2,000 more than a 15 SEER unit. If the 18 SEER unit would reduce your total energy costs by more than $2,000 over its lifespan, you’re probably better off with the 18 SEER unit since it will end up costing you less money in the long run.

Opting for a higher SEER rating often doesn’t make financial sense in cooler climates where an AC would run for far fewer hours each year. In this case, the energy savings would generally never be enough to fully offset the higher cost of the unit. However, choosing a unit with a higher SEER rating can definitely be a smart financial decision in California where your AC will get much more use and run for far more hours every year.

If you have any questions about SEER ratings or want to know more about your options for a new AC or heat pump, you can count on the experts from Comfort Bros Heating, Air & Plumbing for help. We specialize in AC and heating installation as well as all types of HVAC repairs and maintenance for customers in El Cajon and throughout the San Diego area. If you’re looking to replace your existing AC unit or add a central air conditioning system to your home, contact us today to schedule an AC installation consultation.

Meet the Author
Nicholas Gildark
Nicholas Gildark

Nicholas Gildark is a San Diego native who comes from a tight knit family and enjoys spending time with them. Nicholas is engaged to his beautiful fiance Allison Velasquez. The two of them recently purchased a home.
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