How do I choose the right standby generator size for my home in New Brunswick?

Choosing the right standby generator for your New Brunswick home means matching the generator's capacity to your actual power needs — not guessing or buying the biggest unit available. An undersized generator won't keep your essential systems running during the extended Maritime outages we're known for, while an oversized one wastes thousands of dollars on capacity you'll never use.

Why Standby Generators Matter in New Brunswick

New Brunswick experiences some of the most frequent and prolonged power outages in Atlantic Canada. Ice storms, nor'easters, post-tropical storms, and heavy wet snow regularly knock out NB Power service for hours, days, or even weeks in rural areas. The 2017 ice storm left parts of the Acadian Peninsula without power for over a week. Homes in areas like Miramichi, Bathurst, Campbellton, and the Upper Saint John River Valley are particularly vulnerable due to long transmission line runs through heavily forested terrain.

Unlike a portable generator that you wheel out and connect with extension cords, a standby (whole-house) generator is permanently installed, connected to your panel through an automatic transfer switch, and starts within 10–30 seconds of detecting a power failure. It runs on natural gas (where available — limited areas along the Moncton-to-Saint John corridor) or propane (the standard for most of New Brunswick).

Step 1: Calculate Your Essential Load

List everything you want to power during an outage and add up the wattage:

Critical loads (must have):
| Item | Running Watts | Starting Watts |
|------|--------------|----------------|
| Refrigerator | 150–400W | 800–1,200W |
| Freezer | 100–300W | 600–1,000W |
| Well pump (1/2 HP) | 750W | 1,500–2,000W |
| Sump pump (1/3 HP) | 500W | 1,000–1,500W |
| Furnace blower (gas/oil) | 500–800W | 1,500–2,000W |
| LED lighting (10 fixtures) | 100–200W | Same |
| Internet modem + router | 30–50W | Same |
| Phone chargers | 20–50W | Same |

Important loads (strongly recommended):
| Item | Running Watts | Starting Watts |
|------|--------------|----------------|
| Electric water heater (40 gal) | 4,500W | Same |
| Microwave | 1,000–1,500W | Same |
| Washing machine | 500W | 1,200W |
| Sump pump (backup) | 500W | 1,000W |

Comfort loads (nice to have):
| Item | Running Watts | Starting Watts |
|------|--------------|----------------|
| Electric baseboard heat (per room) | 1,000–2,000W | Same |
| Heat pump (mini-split) | 1,500–3,000W | 3,000–6,000W |
| Electric dryer | 5,000W | Same |
| Electric range | 2,000–8,000W | Same |
| Window AC | 1,000W | 2,000–3,000W |

The critical distinction for New Brunswick: If your home has electric baseboard heat (extremely common in NB), powering even a few rooms of heat adds 3,000–6,000+ watts to your generator requirement. This single factor is what pushes many NB homeowners from a modest generator into a larger unit.

Step 2: Account for Starting (Surge) Watts

Motors in well pumps, sump pumps, refrigerator compressors, and heat pump compressors draw 2–3 times their running wattage when starting. Your generator must handle the highest simultaneous starting surge, not just the running total.

A good rule: take your total running watts and add the single largest starting surge. For example:

• Total running: 8,000W


• Largest surge (well pump): +1,500W


• Generator minimum: 9,500W running capacity

Step 3: Choose Your Generator Size

10–12 kW: Covers essential loads for a small to medium home without electric heat. Powers well pump, refrigerator, freezer, furnace blower, lights, and a few outlets. Good for homes with oil or gas heat. Price: $4,000–$6,000 for the unit.

16–20 kW: The most popular size in New Brunswick. Handles essential loads plus some baseboard heat (2–3 rooms), a heat pump, electric water heater, and most kitchen appliances. Suitable for most 3-bedroom homes. Price: $5,500–$8,000 for the unit.

22–26 kW: Powers most of a medium to large home including significant electric heating, electric range, dryer, and multiple heat pumps. The right choice for larger homes in Fredericton, Quispamsis, or Riverview with all-electric systems. Price: $7,000–$12,000 for the unit.

30+ kW: Full whole-house power for large homes with extensive electric heat, multiple zones, workshops, hot tubs, or commercial-level needs. Rarely needed for typical residential. Price: $10,000–$18,000+ for the unit.

Step 4: Fuel Considerations for NB

Propane (most common in NB):

• Available everywhere in the province via delivery


• Requires a propane tank installation (500–1,000 gallon is standard for generators)


• A 20 kW generator running at 50% load uses roughly 2–3 gallons per hour


• A 500-gallon tank provides roughly 4–7 days of continuous operation at moderate load


• Propane tank rental or purchase: $500–$2,500 depending on size and whether you rent or buy


• Propane delivery is available from providers like Superior Propane, Irving Energy, and local suppliers across NB

Natural gas:

• Only available in limited areas (parts of Moncton, Dieppe, Riverview, Saint John, Fredericton via Liberty Utilities)


• Unlimited fuel supply during outages (gas lines are buried and rarely affected by storms)


• Slightly lower running cost than propane


• If you already have natural gas service, this is the obvious choice

Diesel:

• Some larger standby generators run on diesel


• Fuel is easily available but requires on-site tank storage


• More efficient than propane but noisier and requires more maintenance


• Less common for residential installations in NB

Total Installation Cost

| Component | Cost Range |
|-----------|------------|
| Generator unit (16-22 kW) | $5,500–$10,000 |
| Automatic transfer switch | $500–$1,500 (often bundled) |
| Concrete pad | $300–$600 |
| Electrical installation (licensed electrician) | $1,500–$3,000 |
| Propane tank + connection | $500–$2,500 |
| TSANB electrical permit | $75–$200 |
| Gas permit (propane connection) | $75–$150 |
| Total installed | $8,500–$18,000 |

TSANB and Permit Requirements

Standby generator installation in New Brunswick requires:

Electrical permit from TSANB — for the transfer switch connection to your panel

Gas permit — for the propane or natural gas connection (separate from the electrical permit)

Setback compliance — generators must be placed a minimum distance from windows, property lines, and air intakes (typically 5 feet from windows, 18 inches from the house wall)

Noise bylaws — check your municipality's noise ordinances; standby generators typically produce 65–75 dB at 7 metres

Your electrician and propane company typically coordinate the permits. The TSANB inspection covers the electrical connections, while a separate gas inspection covers the fuel connection.

Maintenance for Maritime Conditions

New Brunswick's salt air (coastal areas), extreme cold, and humidity require attention:

• Weekly automatic exercise: Most standby generators run themselves for 15–20 minutes weekly to stay ready


• Annual service: Oil change, filter replacement, spark plug check — $200–$400 per year through an authorized dealer


• Battery replacement: Every 2–3 years (cold NB winters are hard on batteries) — $50–$100


• Coolant check: For liquid-cooled units (22 kW+), antifreeze must be rated for our -30°C winter temperatures


• Rodent protection: Mice and squirrels nesting in generator enclosures is a real problem in rural NB; check housing vents and wiring regularly

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