Beta. This tool is live for real-world testing. Run your numbers and tell us what to fix — nothing is uploaded or stored.

For homeowners

SEER2 Energy Savings Calculator

Compare your old AC against a new high-efficiency system and see what the upgrade is actually worth in dollars — before you believe a sales pitch.

How it works: enter your old system's rating, the new system's SEER2, your system size, how many full-load cooling hours your climate runs, and your electric rate. The tool compares both systems on the same SEER2 ruler and shows yearly savings — plus whether those savings alone ever pay for the install.

Your system

Your old system's rating is…

Pre-2023 SEER SEER2 already

Old rating

Find it on the outdoor unit's nameplate. Pre-2023 units show SEER; 2023 and newer show SEER2.

System size (tons)

New system SEER2

Equivalent full-load hours per year

Not total runtime — the hours your system would run at full power. Edit it for your climate.

Electric rate (cents per kWh)

Read it off your bill if you can — the preset is a state average, not your plan.

Install cost (optional, $)

Enter it to see the payback period — how many years of energy savings it takes to cover the install.

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Old vs new, per year

Old system
New system
Saved
Saved per month

Good – better – best (same home, same hours, same rate)

Read this before you trust the number.

Estimates, not bill promises. Actual savings depend on ductwork, insulation, thermostat habits, and your real rate. This tool shows a range-shaped answer, not a guarantee.
SEER and SEER2 are different rulers. In January 2023 the DOE test procedure (M1) raised the test pressure from 0.1 to 0.5 inches of water column to reflect real ductwork. The same equipment rates about 4–5% lower under SEER2 — that is why this tool converts your old SEER to its SEER2 equivalent (÷ 1.05) before comparing.
One average rate simplifies your plan. California time-of-use plans can run roughly 20¢ off-peak to 45–65¢ on peak. If you are on TOU, your bill's average rate is the honest input, not the cheapest hour.
Runtime hours are NOT full-load hours. A Las Vegas system may run 2,500–3,500 hours a year in total, but much of that is part-load cycling. Plugging runtime hours into this formula would overstate savings. Use equivalent full-load hours, and edit the preset if your climate differs.
Old systems lose efficiency with age (dirty coils, worn components), so real savings from replacing a very old unit can be larger than shown — but that is not modeled here.

Rates: EIA Electric Power Monthly, July 2026 average residential rates — Nevada 12.77¢/kWh, California 33.61¢/kWh, US 18.31¢/kWh. Conversion and method: see the sources note shipped with this tool.

Next step when the numbers say "maybe": check whether repair or replacement wins for your system in Repair-or-Replace.