Efficiency Upgrade Savings Calculator

Enter the capacity, the two efficiency ratings, the hours the unit runs in a year and what your client pays for electricity. You get the running cost both ways and the yearly saving. Add the installed price and you also get how long the work takes to pay for itself. Every figure is yours; none is supplied.

Cooling capacity

How much cooling the unit puts out, in BTU per hour: a BTU is a measure of heat, so BTU/h says how fast heat is moved. Read it off the data plate or the spec sheet. Use the same capacity for both units: this compares efficiency, not size.

Efficiency rating of the unit coming out

The efficiency rating of what is there now: the SEER or SEER2 number on the data plate. A higher rating means the unit gives the same cooling for less electricity. Both units here must use the SAME kind of rating. SEER and SEER2 are two different scales, and mixing them shows a saving that is not real.

Efficiency rating of the unit going in

The efficiency rating of the unit you are proposing, on the same scale as the one above.

Cooling hours a year

How many hours the unit actually runs in a year, in this town, in this house. Nothing here fills this in: a season length that fits one place is wrong in the next.

Electricity price

What your client pays per kilowatt-hour, from their own bill. Include delivery if their bill does.

Result

Fill in a few more boxes and the answer will show here.

Fill in the calculator first. Then this button saves the whole sheet.

Loading the calculator.

This is a calculator, not advice. Check the numbers against your own records before you price a job.

What an efficiency upgrade is actually worth

An efficiency rating is BTU of cooling per watt-hour of electricity, so the yearly electricity a unit uses is its capacity times the hours it runs, divided by the rating. Double the rating and you halve the power. That is the whole calculation, and it is why the argument for a better unit is arithmetic rather than opinion, as long as the four numbers going into it belong to the house in front of you.

The hours matter more than people expect. A unit running twelve hundred hours a season and the same unit running four hundred are two completely different jobs, and the same upgrade is a clear yes in one and a hard sell in the other. That is why no hours figure is filled in here. The electricity price is the same story: use your client's actual bill, delivery charges included if their bill includes them.

Read payback against the life of the equipment, never on its own. Six years is excellent on a unit you expect to see out fifteen and meaningless on one you expect to last eight. When the saving comes out at zero or below (same rating both sides, or a replacement rated lower than what is coming out), this shows no payback at all rather than a number that flatters the job.

The common mistake is comparing a rating to a rating on a different scale. Put those two side by side and the calculation invents a saving nobody will ever see on a bill. Zeus builds the quote on the phone and sends it as a PDF, so the figure you worked out in the driveway is the figure your client reads that evening.

Built for HVAC work: see the HVAC job app.

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