22 kW Whole House Generator Cost $5,748 to $6,406 for the Unit in 2026.
The default whole-house spec. Covers a 2,500 to 3,500 square foot single family home including a 5 ton central AC, electric range, well pump, and basic EV charging headroom. Outsells every other size in the residential standby market by a wide margin.
UNIT
$5,748 - $6,406
Generator only, listed price
UNIT + SWITCH
$6,667 - $7,355
Listed, before installation
PEAK BTU
~315,000 BTU/hr
Natural gas at full load
Why 22 kW Dominates the U.S. Standby Market
The 20 to 22 kW slot is the default whole-house spec, and every major brand has a unit in it (Kohler's 20RCA and Cummins' RS20A are both 20 kW). The reason is a convergence of three market forces. First, the median new-construction home in the U.S. is roughly 2,300 to 2,500 square feet (Census Bureau housing survey) and is built with a 3.5 to 4 ton central AC. Second, that home's peak electrical demand sits in the 18 to 20 kW range with the AC running, so 22 kW gives 10 to 20 percent headroom for surge events and electrification growth. Third, the price gap from 18 kW (the next size down) is small enough that the up-spec is an easy sell.
From the installer side, 22 kW is also the easiest install at the high end of residential. Site prep is much the same as for an 18 kW or 26 kW air-cooled unit. The 200 amp service- entrance transfer switch is the standard spec and electricians are practiced at the wiring. The gas line typically needs upsizing from three quarter inch to one inch but rarely beyond, so gas piping costs are predictable. Permits are familiar to local building departments because the 22 kW size has been the standard residential spec for over a decade.
From the resale-value side, 22 kW is the spec that real estate agents recognise and price into listings. Smaller generators (10 to 14 kW) do not move the needle on listings; larger liquid-cooled generators cost far more to buy and install.
22 kW Brand and Model Comparison
All four main brands have a unit in the 20 to 22 kW slot, though not all at 22 kW: Kohler's 20RCA and Cummins' RS20A are 20 kW, while Generac and Briggs and Stratton build to 22 kW. Checked on 8 Oct 2026, the four listed unit prices spread $658 from cheapest to dearest. Compare the rating you need, not the model name.
| Brand | Model | Listed unit price | Note |
|---|---|---|---|
| Cummins | RS20A (20 kW) | $5,748 | Quiet Connect line has no 22 kW model. |
| Kohler | 20RCA (20 kW) | $6,016 MSRP | 5-year/2,000-hour limited warranty covering parts, labour and travel. |
| Generac | 7260 22 kW | $6,189 | Generac's newer 22 kW model. The Guardian 7042 ($5,999) is shown as discontinued at AP Electric. |
| Briggs & Stratton | 22kW PowerProtect+ (040787) | $6,406 | 7-year limited warranty. |
Unit prices as listed on 8 Oct 2026: Kohler MSRP from its home generators listing (starting price, installation not included); Generac, Cummins and Briggs and Stratton from AP Electric (7260, RS20A, 040787). Your dealer's price will differ.
What the Installed Price Is Made Of
Generator + 200 A switch, listed
$6,667 - $7,355
Cheapest unit at this size with the $919 Generac switch, through the dearest with the $949 Kohler switch. Prices checked 8 Oct 2026. No installation.
Installation
Quoted per house
Gas or propane connection, transfer switch wiring, pad, permit, commissioning. No maker or national body publishes it by size.
Two installed prices are published. Walton EMC, an electric co-op in Georgia, tells members a Generac 22 kW Response Series averages $9,000 to $10,000 locally for unit and installation at existing homes with natural gas service, and $1,000 to $2,000 more where propane has to be installed (archived copy). The Remodeling Cost vs. Value Report 2025 puts its backup generator job at $13,534 nationally ($11,629 to $15,652 across the nine Census divisions), but that job is a 70 A essential-circuits system on existing propane, smaller than a whole-house install, so treat it as a reference point rather than a price for this size.
Your own installed price turns on the gas run length and pipe size, whether the electrical service needs work, the pad and the local permit. Put your quote into the installation quote checker to see how much of it is installation.
Fuel and Running Cost on a 22 kW Unit
A 22 kW generator at full load on natural gas consumes about 315 cubic feet per hour, or roughly 3.15 therms per hour. At the recent EIA national average residential natural gas price of approximately $1.45 per therm, full load running cost is about $4.55 per hour. The more realistic load during a typical outage is 50 to 60 percent (because the home is not running every appliance simultaneously), which puts running cost at $2.45 to $2.90 per hour or $59 to $70 per 24 hour day. A week-long outage on natural gas costs roughly $415 to $490 in fuel.
On propane, the 22 kW unit burns roughly 3.6 gallons per hour at full load and 2.2 gallons per hour at 50 to 60 percent load. At the recent EIA residential propane average near $2.67 per gallon, that is $5.85 to $9.60 per hour, or roughly $140 to $230 per 24 hour day. A 1,000 gallon residential propane tank (the standard for 22 kW propane installs) holds 800 gallons usable and yields roughly 360 hours of generator runtime at 60 percent load, enough for a 15 day continuous outage. Annual exercise cycle fuel consumption is about 6 gallons of propane per year.
Across a 10 year ownership horizon, the fuel cost delta between natural gas and propane is substantial. Assuming the household experiences an average of 8 hours of outage per year (slightly above the U.S. average per the EIA Electric Power Annual reliability data), the natural gas total is roughly $200 in fuel over 10 years. The propane total is roughly $375 in outage fuel plus $235 for monthly exercise cycles, or $610. The propane fuel premium is meaningful but small next to the cost of the installation.
Who Should Buy 22 kW (And Who Should Not)
The 22 kW spec is right for the median U.S. single family home: 2,200 to 3,400 square feet, single or paired central AC units totalling 3.5 to 5 tons of cooling capacity, gas heat (furnace or boiler), gas water heater, gas range or electric range used selectively during outages, optional second-stage electric resistance heating on a heat pump, and household members for whom an outage longer than a few hours imposes meaningful inconvenience or risk.
22 kW is also the correct spec for a homeowner who is considering future electrification. Adding an EV charger (typically 7,200 to 9,600 watts continuous on a Level 2 connection) does not significantly stress a 22 kW system as long as the dryer and the AC compressor are not both running at the same moment. Adding a heat pump in cooling mode is already accounted for in the existing AC spec. Adding a heat pump in heating mode with full electric backup may push the home to require a 26 kW step-up, but a 22 kW handles the cooling-only case indefinitely.
22 kW is the wrong spec for: very small homes (under 1,500 sq ft) where 14 to 18 kW would do the same job on a smaller unit; very large homes (over 4,000 sq ft with multiple AC zones, hot tub, workshop, EV charger) where 26 to 36 kW is the more durable answer; and homes that are explicitly designed for partial-coverage standby (the homeowner accepts that air conditioning will be off during outages and wants only the essentials covered) where 10 kW makes more financial sense.
One last cohort worth flagging: homeowners in storm-prone regions (Gulf Coast, Atlantic Seaboard, Tornado Alley) where multi-day outages are realistic. For these homes the 22 kW spec earns its keep through the second-day-of-outage scenario, where a 14 kW unit with load-management starts to feel cramped (the household is fatigued, the kids are home from school, the laundry needs doing, the AC must run continuously rather than cycling, the fridge is opened more often). 22 kW handles that scenario without anyone thinking about it.
FAQ
How much does a 22 kW whole house generator cost installed?v
One installed price is published for this size: Walton EMC, a Georgia electric co-op, tells members a Generac 22 kW Response Series averages $9,000 to $10,000 for unit and installation at existing homes with natural gas service, and $1,000 to $2,000 more where propane has to be installed. The four 20 to 22 kW units we priced listed at $5,748 to $6,406 when checked on 8 Oct 2026, and a 200 A service-rated automatic transfer switch lists at $919 (Generac 9929) to $949 (Kohler RXT-JFNC-200ASE) at AP Electric. No maker or national body publishes installation by size, so your quote turns on the gas run, any electrical service work, the pad and the local permit.
Why is 22 kW the most popular size?v
Three reasons. First, it covers the typical 2,500 to 3,500 sq ft home including a 5 ton central AC with margin. Second, it has enough headroom for an EV charger or heat pump conversion in the next 10 years. Third, listed 20 to 22 kW units ($5,748 to $6,406) overlap the 17 to 18 kW units ($5,167 to $6,017), so the unit-price step from 18 kW is small.
What is the difference between Generac 7260 and Kohler 20RCA?v
The Generac 7260 is a 22 kW unit listed at $6,189 at AP Electric; the Kohler 20RCA is a 20 kW unit with a $6,016 Kohler MSRP (starting price, installation not included), both checked on 8 Oct 2026. Generac's published sound figure at this size comes from its Guardian 22 kW spec sheet: 67 dB(A) at 7 m (23 ft) under normal load and 57 dB(A) in exercise, measured from the front. Kohler's 20RCA sheet gives 70 dB(A) at normal operation and 66 dB(A) in exercise, at 7 m (23 ft), by Kohler's own method. The makers measure differently, and the published figures do not show either to be clearly quieter. Kohler's warranty is 5-year/2,000-hour limited, covering parts, labour and travel. Generac reports roughly 9,700 residential dealers (Q2 2026 results).
Do I really need 22 kW for a 2,500 sq ft house?v
If the home has a 3.5 ton or larger central AC, yes. If it has only a 3 ton AC and gas heat with gas water heating, an 18 kW unit will cover it, and 17 to 18 kW units list slightly lower. The 22 kW spec is the right answer when the home has central AC over 3.5 tons OR when the homeowner expects to add electric load (heat pump, EV) within 10 years.
How long does a 22 kW generator last?v
20 to 30 years with annual maintenance. The engine has roughly 10,000 to 30,000 hours of life depending on brand. With a typical 5 to 8 hours of total runtime per year (mostly the weekly 12 minute exercise cycle), even the low-end estimate yields 20+ years of life.
What does it cost to run a 22 kW generator for 24 hours?v
On our fuel model: natural gas, roughly $59 to $70 per 24 hours at a typical 50 to 60 percent outage load, at about $1.45 per therm. Propane, roughly $140 to $230 per 24 hours at about $2.67 per gallon. A week-long outage on natural gas costs roughly $415 to $490 in fuel.
Related decisions
18 kW step-down
Units $5,167 to $6,017 listed. Enough if the AC is 3.5 tons or under.
26 kW step-up
Units $7,019 to $7,546 listed. Two AC zones plus electric loads.
Generac deep-dive
Model 7260 in context of the full line.
Kohler deep-dive
Publishes its own MSRPs. RCA line: 14, 20 and 26 kW.
Cummins deep-dive
Quiet Connect RS line: 13, 17, 20 and 30 kW.
Installation quote checker
See how much of your quote is installation.