14 kW generator
A standby generator in the 14 kW class, such as the Generac Guardian 14, provides 14,000 W with propane and about 12,460 W with natural gas. Ratings for other models vary slightly. Essential circuits are covered, and on natural gas the unit also runs a 3-ton central AC. Central air for a whole house calls for a larger unit.
For natural gas, an installed 14 kW unit begins at $8,849 in Arkansas. In Oregon the price reaches $11,149. State labor figures are based on BLS wages, May 2025.
Will 14 kW suit your house? Use three questions to size it, counting the AC or well pump start.
What a 14 kW generator runs
| Loads running together | Running | Peak at a motor start | Natural gas | Propane |
|---|---|---|---|---|
| Essentials | 4.5 kW | 5.6 kW | runs | runs |
| Essentials and a 1 hp well pump | 6.5 kW | 8.5 kW | runs | runs |
| Essentials and a 2-ton central AC | 7.0 kW | 9.0 kW | runs | runs |
| Essentials and a 3-ton central AC | 8.0 kW | 10.5 kW | runs | runs |
| Essentials and a 4-ton central AC | 9.5 kW | 12.5 kW | too small | runs |
The essentials list covers lights, TV, a router, a microwave, a 1/2 hp sump pump, a fridge, a freezer and the furnace blower. The "runs" figure keeps running loads under 80% of the rating and includes coverage for the largest motor start on top.
| Whole house load | Natural gas | Propane |
|---|---|---|
| No central air | up to 2,000 sq ft | up to 3,000 sq ft |
| Central AC, 3 ton | essential circuits only | essential circuits only |
| Central AC, 4 ton | essential circuits only | essential circuits only |
Whole house rows use the NEC 220.83 method: 3 VA per sq ft for lights and outlets, plus gas heat and the kitchen and laundry circuits, with no electric range, electric dryer or electric water heater. Check your own home.
Hourly fuel consumption
| Load | Natural gas | Gas cost | Propane | Propane cost |
|---|---|---|---|---|
| 25% | 165 cu ft | $3.61 | 1.18 gal | $3.22 |
| 50% | 195 cu ft | $4.27 | 1.81 gal | $4.94 |
| 75% | 226 cu ft | $4.94 | 2.44 gal | $6.66 |
| 100% | 256 cu ft | $5.61 | 3.07 gal | $8.38 |
For the Guardian 14 kW, Generac's fuel table shows half load and full load, with the 25% and 75% values read in between. Costs come from EIA US average prices.
How long a propane tank lasts
| Tank | 25% load | 50% load | Full load |
|---|---|---|---|
| 120 gal | 81 h | 53 h | 31 h |
| 250 gal | 169 h | 110 h | 65 h |
| 500 gal | 339 h | 221 h | 130 h |
| 1,000 gal | 678 h | 442 h | 261 h |
Tanks fill to 80%.
What installation costs
| Line, 14 kW | Natural gas | Propane | Basis |
|---|---|---|---|
| Generator | $4,889 | $4,889 | The 14 kW bundle, less the switch, at Generac list price. |
| Transfer switch | $1,060 | $1,060 | Generac's listing gap, comparing the switch version against the version without it |
| Electrician: switch, wiring, start-up | $3,000 to $5,500 | $3,000 to $5,500 | Install ranges already published, set to the US average hourly wage of $34.37 (BLS) |
| Fuel line | $500 to $2,000 | $800 to $2,500 | a gas line that runs from the meter; a propane line that runs from the tank |
| Pad and permit | $300 to $1,200 | $300 to $1,200 | composite pad or slab, local fees |
| Installed | $9,749 to $14,649 | $10,049 to $15,149 | propane leaves out the tank |
State figures on whole house generator cost
The 14 kW size and other brands
| Brand | Model at 14 kW or next up | List price | Installed, natural gas | Page |
|---|---|---|---|---|
 Generac | Guardian 14 kW, with switch | $5,949 | $9,749 to $14,649 | Generac cost |
 Kohler | 14 kW 14RCA, plus a switch | $5,098 | $9,958 to $14,858 | Kohler cost |
Four items get added to every unit's installed price: the gas line, the electrician, the permit and the pad. A unit sold without a switch also gets Generac's switch price for the closest size added on. List prices come from Generac and Kohler's own pages. Dealers sell Cummins, Briggs & Stratton and Champion units, and each dealer quotes the unit: Cummins cost, Briggs & Stratton cost, Champion cost.
Sizes: 10 kW model 18 kW model All sizes