The efficiency worksheet
Put efficiency in perspective.
A higher efficiency rating is useful. Understanding what it could mean for your cooling costs is even more useful. Start with your own assumptions.
Explore your cooling-cost scenario.
Use your numbers.
Use cooling-only electricity, not your entire household bill. Compare two ratings on the same test basis; do not mix SEER with SEER2.
Enter all four values to see your scenario. Example placeholders are not your estimated usage or our pricing.
Calculation: proposed cooling kWh = current cooling kWh × existing rating ÷ proposed rating. Assumes identical cooling demand and comparable ratings. Weather, ducts, sizing, controls, degradation, and actual part-load performance can change the result. Fixed electric-bill charges and heating are excluded.
Use a cooling-only baseline.
Your total electric bill includes appliances, lighting, water heating, and other uses. Multiplying the entire bill by an AC efficiency percentage overstates the opportunity. Use a cooling estimate from your utility or energy-monitoring system when available.
If you estimate cooling consumption from seasonal bills, record the assumptions and account for other changes in usage. Fixed delivery charges and base fees do not necessarily fall when cooling kWh falls.
Compare like with like.
SEER and SEER2 use different test procedures. This worksheet intentionally asks you to select one rating basis for both systems. If the existing system has only a SEER rating and the proposal only has SEER2, ask the contractor for a defensible comparison rather than treating those numbers as interchangeable.
For a new split system, use the rating of the exact outdoor and indoor combination. An “up to” number in an advertisement may describe a different match.
Efficiency alone does not describe noise, humidity control, installation quality, or warranty coverage. Compare the upgrade premium alongside those features and the time you expect to own the system.
What this calculator leaves out.
This is a proportional efficiency model, not a building-energy simulation. It holds cooling demand constant and does not model weather, occupant behavior, changing ducts, equipment degradation, or heating. A positive result is an illustrative reduction, not a guarantee of utility-bill savings.
Comfort starts with clarity
Your next step can be a clear one.
Explore the current installed estimates, or bring us your quote and questions.