What Size Portable Generator Do I Need?

You're researching portable generators and seeing numbers like 3,500W, 7,500W, and 10,000W — but what do those numbers actually mean for your home? Here’s how to understand generator sizing in terms of real rooms, real appliances, and real needs.

​“Don’t buy a generator based on square footage — buy it based on what you actually need to keep running when the power goes out.”

Understanding Generator Sizes in Real-World Terms

​Wattage = how much your generator can power at once.
When shopping, you’ll see:

• Running Watts — what it can handle continuously
• Starting Watts — extra power needed to get things like fridges or sump pumps going

Here’s how that plays out in real life:


🔌 3,000–4,000 Watts
Can typically power:

• 1 refrigerator
• 1 sump pump or well pump
• A few outlets and LED lights
• Phone/laptop charging
• Possibly a furnace blower (but not guaranteed)

Good for:
Basic storm protection — ideal for cabins, smaller homes, or covering just the bare essentials


🔌 5,000–7,000 Watts
Can typically power:

• Refrigerator and separate freezer
• Sump pump or well pump
• Furnace blower (forced-air heat)
• TV or small media setup
• A few lights and general-use outlets

Good for:
Most homes in the Northeast Suburbs. Covers what your family needs to stay warm, dry, fed, and connected during a typical outage.


🔌 8,000–10,000+ Watts
Can typically power:

• All of the above
• Microwave or small kitchen appliances
• Small window A/C or mini split
• Washer/dryer (one at a time)
• More rooms/lights/outlets across the house

Good for:
Larger homes or families who want extra comfort and flexibility — or who experience more frequent outages


Skyline Tip: Think in priorities, not rooms. What matters most: keeping food cold? staying dry? heating the house? We’ll help size your system based on your reality — not a sales chart.

Gas vs. Propane — and Why It Changes Output

​Your fuel type doesn’t just affect storage — it affects power.
Many dual-fuel generators produce slightly less power on propane than they do on gasoline. It’s a normal difference, but one you should plan for.
🔁 Example (Typical Dual-Fuel Ratings):

• Gasoline: 9,500 running watts / 12,000 starting watts
• Propane: 8,500 running watts / 10,800 starting watts

That’s often a 10–15% drop in capacity when running propane instead of gas.


Which Fuel Is Right for You?
⛽ Gasoline

• Widely available
• More power output
• Shorter shelf life — needs stabilizer for long-term storage

🔥 Propane

• Burns cleaner, quieter
• Can be stored long-term without degrading
• Slightly lower power output
• Requires tank storage and hose setup

💡 Dual-Fuel

• Switches between gas and propane as needed
• Great for homes with backup grill tanks
• Offers flexibility during outages or fuel shortages

Skyline Tip: If you plan to rely on propane, size up slightly — or confirm your generator still covers your essential loads at the reduced output.

What We See in the Northeast Suburbs

​In places like White Bear Lake, Roseville, and nearby neighborhoods, portable generators are one of the most requested upgrades — especially after big summer storms or winter outages.
Here’s what local homeowners often tell us:

• “I just want to keep the fridge, freezer, and sump pump going.”
• “I have a well or septic system and can’t risk losing power for long.”
• “My kids need heat or Wi-Fi during an outage — even if the rest of the house is dark.”
• “I don’t want to run extension cords everywhere — I want a clean hookup.”

We help families match the right size generator to their real-life needs — and install safe, code-compliant transfer switches to make it easy.

When You Don’t Trust the Weather — Trust Skyline Electric

Choosing the right portable generator shouldn’t be confusing or overwhelming.
Whether you already own one or are just starting your research, we’ll help you figure out what size is right — and how to connect it safely, cleanly, and confidently.
No guesswork. No pressure. Just trusted help — from a team that’s in your neighborhood every day.