AC Savings Calculator for Florida Homes
Liberty Air and Electric built this calculator on a typical year of Florida weather, hour by hour, from the weather station nearest your ZIP. Orlando and Fort Lauderdale get different answers because they get different weather. Put in your ZIP and what you have now.
Every answer below is optional. The estimate above already runs on typical Florida assumptions, and each one you correct replaces an assumption with a fact about your house.
Tell us about your current system
Leave these alone if you do not know. A 15 year old system at 12 SEER is the safe assumption and it is what we use.
Tell us about your new system
Skip this if you are still shopping. The efficiency level above already carries typical ratings. If you have a quote in hand, the exact numbers are on its AHRI certificate.
Both numbers are on the AHRI certificate. Enter both or neither. HSPF2 is the heating rating, and in Florida it can be worth more than the cooling number.
Tell us about your house
Estimated values only, not a quote. We are an open book about the math behind them. Read the methodology.
How This Calculator Works
Liberty Air and Electric runs your system through a whole year of weather, one hour at a time. Every hour gets sorted by how hot it was outside, and the calculator prices out what your AC costs to run at that temperature. Add all the hours up, and you have the cost to run your AC for the year. Contractors call this the bin-hour method, because each one-degree group of hours is a bin. It's the same math that sizes equipment for the hottest day of the year, just run across every hour instead of one.
How many hours a Florida AC actually runs
Liberty counts the hours your AC has to run. That's about 2,410 a year around Orlando and about 3,290 in Fort Lauderdale. Those are equivalent full-load hours, meaning the hours a system would run if it ran flat out the whole time instead of cycling on and off. Most savings calculators skip the counting and start from a published hours figure, then scale it by how much more efficient the new equipment is. Those published figures came out of national tables built decades ago, and the Fort Lauderdale count here runs above them because the tables were built on 1990s weather. Florida has gotten hotter since.
The balance point moves with your thermostat
Your AC kicks on before it gets as warm outside as your thermostat setting. People, lights, appliances and sun are all putting heat into the house, so the house needs help before the outdoor temperature ever catches up to the number on the wall. With the thermostat on 75, it has to drop to about 68 outside before the house sheds enough heat on its own and the system can stay off. That crossover temperature is the balance point, and the calculator works it out from whatever setpoint you enter. Move the thermostat down a degree and two things happen at once. First, the crossover moves down with it, so hours the system used to sit out now have it running. Second, in every hour it was already running, it's holding a bigger gap between inside and outside, and a bigger gap costs more per hour.
The thermostat moves more money than the equipment
Put in the temperature you actually keep the house at, not the one you figure you should. On a 3-ton Orlando system, cooling runs about $998 a year at 78 degrees and about $1,665 at 72.
Where you set the thermostat moves the bill more than which system you buy. At 75 degrees, the cheapest system that meets code and the most expensive on the lot are about $354 a year apart. On one mid-range system, holding 78 versus holding 72 is about $406 apart. The thermostat moves the bigger number, and you're the one who sets it. That's why the calculator asks for cooling and heating setpoints separately.
Your old system is modeled at what it does now
Liberty models your old system at what it does now, not at what it did new. The calculator takes about 1% off its rating for every year it's been running, capped at 20 years. The efficiency rating scale also changed in 2023, so comparing the old SEER with the new SEER2 doesn't give you the right answer without an adjustment. This calculator covers the adjustment. The lab rating isn't taken at face value either. Each hour, both systems get priced at what they actually deliver in that hour's weather and workload, which runs below what a controlled lab test produces.
The wear number is the one worth arguing with
Liberty flags this one because it moves the answer a lot and it's the assumption you're best placed to correct. Published figures for efficiency loss run about half a percent to one percent a year, from coil fouling, charge drift and wear. The calculator uses one percent, the top of that range, because most systems we open up have been neglected. On a well-kept system one percent is usually too harsh, and the estimate will read high.
Check the box marked We keep up with maintenance on it under your current system and the wear rate halves. On a 15-year-old 12-SEER unit that moves the old system up from about 8.9 SEER2 to about 9.7. It's running better, so a new one has less ground to make up, and the estimated annual saving drops by roughly a fifth. A system with clean coils, correct charge and a changed filter really does hold more of its rating.
Heating is computed separately, and it is not small
Liberty techs know the heating side isn't small in Florida, so the calculator computes it separately. Electric strip heat runs at a coefficient of performance of 1.0, one unit of electricity in, one unit of heat out. A heat pump in Florida winter weather usually runs three or better, three units of heat out for one unit of electricity in. The calculator follows the heat pump down as the outdoor temperature drops, because a heat pump puts out less heat and draws more power the colder it gets, and it turns the strip heat on for the hours the heat pump can't carry alone. The coldest temperature your area sees in a normal winter sets how much heat the house needs. It does not set the heat pump's efficiency. Each hour gets priced at the efficiency the heat pump actually has at that hour's temperature, so a mild Florida winter gets credited as mild. Near Orlando the heating side comes to close to half the annual saving.
How humid the house actually gets
Liberty treats cooling a Florida house as two jobs, dropping the temperature and pulling the humidity out. The calculator splits the work the same way, into the part that cools the air, called sensible, and the part that dries it, called latent. Then it keeps a running tally of the moisture. Moisture comes in through leaks around doors, windows and ducts, and off the people living there. The coil takes moisture back out, condensing it and draining it away. Wherever those two settle is the humidity you live in. One piece of that stays fuzzy. When the compressor shuts off and the blower keeps running, some of the water sitting on the wet coil evaporates straight back into the air, and how much varies more than anything else in the model.
Where the Numbers Come From
Liberty publishes every source, so you can check the math yourself.
Weather
TMYx files, which stitch one typical year of hourly weather together out of real records from 2009 through 2023. They come from the climate.onebuilding.org archive and are built from NOAA Integrated Surface Database observations, with ERA5 reanalysis data filling any gaps in the record. About 25 Florida airport stations. Liberty reads the hourly temperature and humidity readings out of those files and sorts them into a table for each station, never republishing the raw files.
ZIP to station
The 2025 Census ZCTA Gazetteer, public domain, which gives the center point of every ZIP code area. The calculator measures straight-line distance from that point to each weather station and takes the closest one.
Electric rate
The Florida residential average of 15.4 cents per kWh, from U.S. Energy Information Administration reporting for April 2026. It's a starting point, so the field is editable. FPL territory generally runs below that average and Duke Energy Florida above it.
Equipment ratings
The three tiers carry representative SEER and HSPF2 ratings for builder-grade, mid-range and high-efficiency equipment. SEER is the cooling rating, HSPF2 is the heating one. We quote SEER because that's how equipment gets shopped, and the math converts everything to SEER2, the newer test the ratings get measured under now, before it compares anything. The exact ratings for a specific system are printed on its AHRI certificate. Put in both numbers, because a cooling rating on its own leaves the calculator running the heating side off a mid-range guess.
What This Calculator Cannot Know
Liberty techs show the uncertainty on every figure the calculator prints.
The house itself
Liberty can't see your house from a ZIP code. Leaky ducts, thin attic insulation, a wall of west-facing glass with no shade on it, all of that moves your real power bill and none of it shows up in a ZIP code. So the calculator works backward off the size of the system you already have, figuring whoever installed it sized it to the house. That's a decent assumption most of the time and it's sometimes wrong, which is most of why the range runs 15% either side.
Coastal ZIPs draw a milder station
Liberty checks which weather station a ZIP got matched to before trusting the answer. All 1,013 Florida ZIP codes map to one of 27 stations, and around Orlando those stations sit close enough together that a Wedgefield or Sanford answer is almost always solid. Coastal ZIPs are the ones to watch. A station sitting on the shoreline can read milder than a neighborhood a few miles inland. Put in a ZIP outside Florida and the calculator tells you it can't answer.
The weather file is a fifteen-year average
A TMYx file describes one representative year built out of fifteen years of recorded weather. So the savings estimate is a long-run average. That's what you want when you're buying equipment that stays in the house for fifteen years, and it won't tell you what one August bill will be.
The humidity band is wide on purpose
Liberty shows a much wider band on the sticky-hour count than on the dollar figure, on purpose. The water that evaporates back off a wet coil between cycles is the one number the published studies disagree on most, and it feeds the sticky-hour count directly.
No health claims, at all
The calculator counts hours when the air inside would be damp enough to feel sticky, and that's the whole of it. It says nothing about mold, allergens or air quality. Those depend on things a temperature and humidity model can't see.
What a New AC Actually Pays Back
A savings figure is one piece of the decision. Replacing a worn-out system with almost anything modern pays for itself in energy. Stepping from a mid-range system up to a high-efficiency one is a much thinner dollar case, because the only money in play there is the difference between two new units. Liberty walks through that comparison on whether an energy efficient AC is worth it in Florida, using this same engine. --- ## FAQ answers
If the system is already failing and you're deciding repair or replace, the money math is different. AC replacement in Florida covers what a changeout involves and what it costs in this market.
Questions?
Questions About the AC Savings Calculator
Q: How accurate is an AC savings calculator?
A: An AC savings calculator is accurate to a range, and this one prints that range right on the result. The dollar figure carries a band of about 15% either side of the middle number. That band covers what nothing can see from a ZIP code, like leaky ducts, thin insulation, and how many people live in the house. The weather, the equipment ratings and the electric rate are the parts it does know well.
Q: What weather data does this calculator use?
A: This calculator uses TMYx weather files, which build one typical year out of real hourly records from 2009 through 2023, at roughly 25 Florida airport stations. Your ZIP gets matched to the nearest station by distance. Every hour of that typical year is then sorted by outdoor temperature into one-degree groups, so an Orlando answer and a Fort Lauderdale answer come from genuinely different weather rather than one statewide average.
Q: Why does the calculator ask for my ZIP code instead of my city?
A: The calculator asks for a ZIP code because how hard an AC has to work in Florida changes faster than city lines do. A ZIP gets matched to the nearest weather station, and the gap between stations is real money. The same 3-ton system runs about 2,410 hours a year at full load around Orlando and about 3,290 in Fort Lauderdale. A city name would average that spread away.
Q: Does a higher SEER rating always save money in Florida?
A: A higher SEER rating always cuts energy use in Florida, but it does not always save money, because the price gap between tiers can outrun the energy it buys back. Replacing a worn-out 12-SEER system with almost anything modern pays. Stepping from a mid-range system to a top-of-line one is a much thinner case, and this calculator will show you your own version of it.
Q: What is HSPF2 and why does the calculator ask for it?
A: HSPF2 is the heating efficiency rating on a heat pump, and the calculator asks for it because a Florida home running electric strip heat spends real money on heating, and a cooling rating tells you nothing about that. SEER measures the summer side only. HSPF2 is the winter number, the counterpart to SEER2. Near Orlando the heating side is close to half the annual saving, and a calculator that only asked for SEER would understate it.
Q: Why does the calculator ask for my thermostat setting?
A: The calculator asks for your thermostat setting because it moves the answer more than almost anything else you enter, including which equipment tier you pick. On a 3-ton Orlando system, cooling runs about $998 a year at 78 degrees and about $1,665 at 72, same house and same equipment. Enter the temperature you actually hold.
Q: Why does the calculator ask for two temperatures?
A: The calculator asks for two temperatures because almost nobody heats and cools to the same number. A house held at 75 in summer is rarely held at 75 in winter, and the heating math and the cooling math each run off their own setting. Use one number for both and the calculator would have the heat kicking on at the wrong outdoor temperature, which throws off how many hours it runs all winter.
Q: What does the calculator assume about my current system?
A: The calculator assumes your current system is 15 years old and rated 12 SEER unless you tell it otherwise, and it flags both as assumptions in the result. It then applies about 1% efficiency loss per year, capped at 20 years, so a 15-year-old 12-SEER unit is modeled at roughly the efficiency it has now rather than the number on its nameplate.
Q: How much efficiency does an AC lose as it ages?
A: An AC loses roughly half a percent to one percent of its efficiency a year as it ages, from coil fouling, refrigerant charge drift and general wear. This calculator uses one percent and caps it at twenty years, which is the pessimistic end of the published range. A maintained system holds more of its rating, so ticking the maintenance box halves that rate and lowers the estimated saving.
Q: Does regular maintenance change what a new AC would save me?
A: Regular maintenance changes what a new AC would save you, and it lowers the number rather than raising it. A well-maintained old system is still performing closer to its original rating, so there is less ground for a new system to make up. On a 15-year-old unit, halving the assumed wear moves the estimated annual saving down by about a fifth.
Q: What counts as a sticky hour?
A: A sticky hour counts any hour the dew point inside the house would sit above 62°F. Dew point is the temperature at which air starts dropping its water back out, so it tracks how much moisture is really in the air no matter where the thermostat sits. Relative humidity moves when the thermostat moves, which would let your setpoint count twice in the same number. The 62°F line matches the humidity ceiling in ASHRAE Standard 55, and it is also where the gap between one system and another shows up clearest in the data. Liberty reports whole sticky days off the same run too. That day count is a blunter measure, because a day the house only goes over the line for an afternoon doesn't count at all.
Q: Is this calculator a quote?
A: This calculator is not a quote and not a guarantee. It is an energy estimate built from typical-year weather, published equipment ratings, and an electric rate you can edit. Real bills move with how many people are home, what shape the ducts are in, and weather that is never actually typical. Liberty Air and Electric gives real prices in writing after someone has looked at the actual system.
Q: Do I need to enter my exact SEER2 and HSPF2 numbers?
A: You do not need exact SEER2 and HSPF2 numbers to use the calculator, because each of the three efficiency tiers already carries a representative pair. If you have a quote in hand, both numbers are printed on the AHRI certificate and worth entering. Put in both, though. A cooling number entered without its matching heating number leaves the calculator running the whole heating side off a mid-range default.