The HVAC industry continues to evolve as the U.S. Department of Energy (DOE) updates efficiency standards to promote energy savings and reduce environmental impact. One of the most important recent updates affects how HVAC systems are rated using SEER, EER and HSPF values. These ratings help homeowners, contractors and manufacturers understand how efficient a system is and whether it meets the latest federal requirements.
This blog breaks down everything you need to know about the new DOE updates, how they impact energy efficiency ratings, and what these changes mean for you.
Understanding SEER: Seasonal Energy Efficiency Ratio
Before discussing the DOE updates, it’s essential to understand the seasonal energy efficiency ratio because SEER is central to how cooling efficiency is measured.
What Is Seasonal Energy Efficiency Ratio?
The seasonal energy efficiency ratio (SEER) is a metric used to measure how efficiently an air conditioner or heat pump cools a space over a typical cooling season. It is calculated by dividing the total cooling output by the electrical energy consumed during the same period.
In simpler terms, what is seasonal energy efficiency ratio?
It is a rating that tells you how efficiently your cooling system turns electricity into cool air.
What Is a Good Seasonal Energy Efficiency Ratio?
A higher SEER rating means higher efficiency. Today:
- Standard systems typically start around SEER 14–15
- High-efficiency units range from SEER 18–26+
The DOE update impacts these minimum requirements depending on region (North or South).
Understanding EER: Energy Efficiency Ratio
While SEER measures seasonal performance, EER measures cooling efficiency under specific test conditions, typically involving higher outdoor temperatures.
DOE’s new regulations adjust how these ratings are calculated and how manufacturers certify equipment performance.
Understanding HSPF: Heating Seasonal Performance Factor
For heat pumps, the heating seasonal performance factor (HSPF) is the heating equivalent of SEER. It evaluates a system’s heating efficiency across an entire season.
How Is Heat Pump Heating Seasonal Performance Factor HSPF Calculated?
Many wonder, how is heat pump heating seasonal performance factor HSPF calculated?
HSPF is determined by dividing the total heat output (in BTUs) by the total electricity consumed (in watt-hours) throughout a heating season. Higher HSPF means better heating efficiency.
What Did the DOE Update Change?
The DOE’s latest update introduced new minimum efficiency requirements and new testing procedures for determining SEER, EER and HSPF ratings. Here’s how the update impacts the industry:
1. Transition to SEER2, EER2 and HSPF2 Ratings
The DOE introduced new rating scales:
- SEER is now measured as SEER2
- EER is now measured as EER2
- HSPF is now measured as HSPF2
These new metrics use modified testing conditions that better simulate real-world static pressures in ductwork, making the ratings more accurate.
Key Impact: Most ratings appear slightly lower because the test is more rigorous. A SEER 16 unit, for example, may show around SEER2 15.2.
2. New Minimum Efficiency Requirements
The required minimum ratings differ based on the region:
- Northern Region: New minimum SEER2: approx. 13.4 (equivalent to SEER 14)
- Southern Region: New minimum SEER2: approx. 14.3 (equivalent to SEER 15)
Because Southern climates run cooling systems longer, the DOE requires higher minimum efficiency there.
3. More Accurate Real-World Efficiency Measurements
The updated testing accounts for:
- Higher external static pressure
- Stricter airflow performance
- More realistic HVAC operating conditions
This results in SEER2, EER2 and HSPF2 values that better reflect real-world usage.
4. Manufacturers Must Redesign Some Units
The new testing and minimum efficiency standards require many HVAC manufacturers to adjust components such as:
- Compressors
- Metering devices
- Blowers
- Condenser coils
Systems designed before the update may not meet the new standards.
5. Impact on Homeowners and Contractors
For Homeowners:
- New systems may cost slightly more upfront
- Lower utility bills due to higher efficiency
- Better long-term comfort and performance
For Contractors:
- Updated installation guidelines
- New labeling requirements
- Inventory changes to meet regional standards
- Get consistent updates on major developments by becoming part of our HVAC association.
How These Changes Affect System Selection
When buying a new HVAC system, it’s important to check whether the unit meets SEER2, EER2 or HSPF2 minimums for your region. A higher SEER2 or HSPF2 means: More efficient performance, Lower operating costs, Increased comfort, Greater long-term savings
If you’re upgrading from an older system, the difference in energy savings can be significant.
Conclusion
The DOE’s latest update brings more precise rating systems, higher minimum efficiency standards, and improved overall performance expectations for HVAC equipment. The shift to SEER2, EER2 and HSPF2 ensures that the ratings better reflect how systems actually perform in real homes.
Understanding seasonal energy efficiency ratio, heating seasonal performance factor, and how heat pump heating seasonal performance factor HSPF is calculated helps homeowners make better decisions when choosing modern HVAC systems.
