10 kW Whole House Generator Cost $3,699 to $3,946 for the Unit in 2026.

What 10 kW Actually Powers

Ten kilowatts is 10,000 watts of continuous running power, with a typical surge capacity around 12,000 to 13,000 watts for two to three seconds. That second number matters because almost every motor in a home (well pump, sump pump, refrigerator compressor, central AC compressor, deep freezer) draws three to seven times its running wattage for the first half second of startup. A 10 kW generator with 13 kW of surge will start one mid-size compressor at a time, not two.

In practical terms, here is what runs comfortably on a 10 kW unit during a power outage: a gas furnace blower (typically 800 to 1,200 running watts), a refrigerator and a separate freezer (combined 1,000 to 1,400 running watts including duty cycle), a well pump or sump pump (running 750 to 1,500 watts depending on horsepower), every interior light circuit in the house (LED lighting on a typical 2,000 square foot home runs 200 to 500 watts at maximum), the television, the modem, the router, and enough outlet capacity to keep two laptops, three phones, and a couple of small appliances going.

What does not run on a 10 kW unit simultaneously with all of the above: any central air conditioner above one ton, any electric water heater drawing 4,500 watts, any electric range element, any electric dryer at 5,500 watts, any tankless electric water heater at 18,000 watts, any electric vehicle charger at 7,200 watts continuous. You can run any one of those, but you cannot run them with the heat, the fridge, and the lights at the same time. The math runs out.

This is the honest framing of a 10 kW system. It is partial coverage. The marketing language from some installers ("whole house") is technically true if the house has no central AC and no major electric appliances, but the typical American home built after 1990 has central air and at least one of the big-three electric loads, so partial-coverage is the more accurate label.

What the Installed Price Is Made Of

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 10 kW Unit

A 10 kW generator at full load on natural gas consumes approximately 140 cubic feet per hour, or roughly 1.4 therms per hour. At the recent EIA national average residential natural gas price of about $1.45 per therm, that works out to roughly $2.00 per hour at full load and closer to $1.00 per hour at the more typical 50 percent load during an outage. EIA residential natural gas price series publishes the underlying rate by state.

On propane the running cost is roughly two to three times higher. A 10 kW unit at full load burns about 1.8 gallons of propane per hour and around 1.0 gallons per hour at 50 percent load. At the recent EIA residential propane average near $2.67 per gallon, that is $4.80 per hour at full load and $2.67 per hour at half load. A 500 gallon residential propane tank holds about 400 gallons usable, which translates to roughly 200 to 400 hours of generator runtime depending on average load. Most propane-fuelled standby installations are sized with a 500 or 1,000 gallon tank for this reason. EIA residential propane price series publishes the weekly average.

The practical takeaway: natural gas is the right fuel pick if a utility gas line reaches the property. Propane is the right pick when natural gas is unavailable (rural and many semi-rural properties) and the homeowner accepts the higher running cost in exchange for the standby capability. Diesel is virtually unused at the 10 kW residential tier; it is overkill for the load size and the fuel storage logistics do not pencil out.

Compare with adjacent tiers