Energy cost · Solar & Backup Power
Whole House Generator Cost
Standby generator, installed
Bottom line: A standby whole house generator costs $6,000 to $11,000 installed on average, according to HomeGuide, and up to $24,000 for large units or long gas runs. Angi reports a national average of $5,157, with most homeowners paying $1,512 to $8,803. A 20 to 24 kW unit costs $5,000 to $6,500 before installation, and labor runs $3,000 to $5,000.
HomeGuide puts a standby generator at $6,000 to $11,000 installed, and $9,500 to $24,000 for units over 20 kW or long distances from the gas meter. Angi's national average is $5,157, with most homeowners paying $1,512 to $8,803.
Cost by size (unit)
| Size | HomeGuide | Size | Angi |
|---|---|---|---|
| 7 – 10 kW | $2,000 – $3,000 | 7.5 – 10 kW | $2,000 – $3,500 |
| 13 – 16 kW | $3,000 – $4,500 | 14 – 18 kW | $4,000 – $5,500 |
| 17 – 20 kW | $4,000 – $6,000 | 20 – 24 kW | $5,000 – $6,500 |
| 22 – 25 kW | $4,500 – $12,000 | 26 – 32 kW | $6,500 – $15,000 |
| 30 – 48 kW | $10,000 – $16,000 | 45 – 48 kW | $16,200 – $21,000 |
Cost by fuel (unit only)
| Fuel | Cost (HomeGuide) |
|---|---|
| Propane | $2,000 – $6,000 |
| Natural gas | $3,000 – $6,000 |
| Diesel | $5,000 – $18,000 |
Cost by brand (unit only)
| Brand | Cost (HomeGuide) |
|---|---|
| Generac (7 – 24 kW) | $2,000 – $5,000 |
| Briggs & Stratton | $2,400 – $15,300 |
| Kohler | $2,700 – $16,000 |
Installation
| Item | Cost | Source |
|---|---|---|
| Installation labor | $3,000 – $5,000 | HomeGuide |
| Labor, long runs or >20 kW | $5,000 – $12,000+ | HomeGuide |
| Standby installation (avg) | $4,520 | Angi |
| Automatic transfer switch | $600 – $2,500 | HomeGuide |
| Concrete pad | $150 – $400 | HomeGuide |
| Permits | $80 – $450 | HomeGuide |
See generator transfer switch cost.
Maintenance
HomeGuide lists annual maintenance at $200 to $650; Angi lists $80 to $300.
Generator or battery?
For battery backup prices, see solar battery cost.
Running costs per day (HomeGuide)
| Fuel | 7 kW | 15 kW | 20 kW |
|---|---|---|---|
| Natural gas | $10 – $20 | $22 – $32 | $30 – $40 |
| Diesel | $32 – $40 | $90 – $110 | $100 – $120 |
| Propane | $60 – $70 | $145 – $165 | $150 – $170 |
Generac by size (unit only, HomeGuide)
7 kW $2,000, 10 kW $3,000, 16 kW $3,800, 20 kW $4,500, 22 kW $5,000, 30+ kW $12,000.
Accessories (HomeGuide)
Battery $70 to $300, cold-weather kit $130 to $500, wireless monitor $200 to $210, smart load manager $130 to $250.
Starting prices by brand (Angi)
Champion $2,000, Briggs & Stratton $3,150, Cummins $3,700, Generac $6,000.
What a whole-house generator is
A standby generator is installed permanently outside the home. It runs on natural gas or propane and starts automatically during an outage through an automatic transfer switch.
Sizing
The right size depends on what you want to power. Some homeowners power the whole house, including the air conditioner. Others choose a smaller unit for essential circuits only.
What affects the price
- Generator size.
- Fuel type and gas line work.
- Automatic transfer switch.
- Concrete pad and placement.
- Permits and inspections.
More on maintenance
Standby generators run a short self-test regularly. They also need oil changes, filter changes and battery checks. Many companies offer maintenance plans.
Placement rules
Generators must be placed a safe distance from windows, doors and vents to keep exhaust out of the home. Local codes and the manufacturer set clearance rules.
Questions to ask
- What size do I need for my home?
- Is my gas meter large enough for the generator?
- What maintenance plan do you offer?
In Texas
Interest in standby generators grew in Texas after the February 2021 winter storm. With hot summers, many Texas homeowners size the generator to run the air conditioner as well.
Sizing a standby generator
Standby generators are sized in kilowatts (kW). The right size depends on what you want to run during an outage:
- Essential circuits only, such as the refrigerator, some lights, the furnace blower, a sump pump, the well pump and a few outlets. This needs a smaller generator.
- Most of the house, including central air conditioning, an electric range or a water heater, which need a much larger generator.
An electrician or generator dealer performs a load calculation, listing the appliances you want to power and their starting and running loads. Air conditioners and well pumps draw a large surge of power when they start, which affects sizing. Load management modules can shed large loads, like the AC, while other appliances run, allowing a smaller generator to serve more of the house.
Fuel options
Natural gas is convenient where available, since it comes from the utility line and does not need refilling. The gas meter and line must be large enough to supply the generator in addition to other gas appliances.
Propane works where natural gas is not available. It is stored in a tank on the property, which must be sized for how long you want to run the generator, and refilled.
Diesel is common for large commercial generators but less common for homes.
Installation steps
- Site selection that meets clearance requirements from windows, doors, vents and property lines, set by the manufacturer and local code.
- Permits for electrical and gas work.
- Pad or base for the generator.
- Gas line from the meter or propane tank.
- Electrical connection with an automatic transfer switch.
- Startup and testing.
Maintenance and exercise cycles
Standby generators run a short self-test, often weekly, to keep the engine ready. They also need regular maintenance: oil and filter changes, spark plugs, battery checks and inspections. Many dealers offer maintenance plans. A generator that is not maintained may fail to start when you need it.
Noise
Standby generators make noise when running and during exercise cycles. Placement away from bedrooms and neighbors, and quieter models, reduce disturbance. Some HOAs and cities have noise rules.
Permits and approvals
A standby generator usually needs an electrical permit, often a gas or plumbing permit for the fuel line, and sometimes approval from a homeowners association. Some areas also regulate noise or setbacks from property lines. Installers typically handle permits, but ask whether their quote includes permit fees, the concrete pad, the gas line and the transfer switch, since these items are often priced separately.
Living with a standby generator
A standby generator starts automatically within seconds of an outage, so day-to-day you rarely think about it. It runs a short weekly or monthly exercise cycle, which you will hear. Most owners schedule annual service with oil, filters and a battery check. Keep the area around the unit clear of plants, snow and debris so air flows freely.
Fuel supply during long outages
A natural gas generator runs as long as the gas supply holds. A propane unit depends on tank size, so check how many days it covers at typical load.
Sources
Electricians in Texas
Our Texas business directory lists 755 electricians across 6 major cities. The ratings below are the average Google rating of the listed businesses in each city, and the review counts are the total number of Google reviews they have received.
| City | Businesses listed | Avg. Google rating | Total reviews |
|---|---|---|---|
| Houston | 285 | 4.5 | 8,557 |
| Dallas | 95 | 4.7 | 4,755 |
| San Antonio | 126 | 4.5 | 11,438 |
| Austin | 100 | 4.6 | 8,868 |
| Fort Worth | 96 | 4.6 | 5,029 |
| El Paso | 53 | 4.5 | 1,052 |
Source: twupro Texas business directory, built from public Google Maps listings.
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