What Size Portable Generator Do You Actually Need?
Size it to your surge watts, not your running watts — most devices with motors need 2–3x more power to start. For most camping/RV use, 2,000–3,500W is enough. For home backup or jobsites, 5,000–7,500W. The three biggest mistakes: buying too small, too big, or the wrong fuel type.
SummaryChoosing a portable generator is about matching surge capacity to your real device list, picking the right fuel for your use case, and avoiding the common traps of over-sizing or under-sizing. Inverter generators are quiet and fuel-efficient; open-frame units are cheaper and more powerful.
The Three Mistakes Buyers Make
Portable generators look simple — small, cheap, easy to carry. But the customers who come back to us with regrets are almost always the ones who bought the wrong size, the wrong fuel type, or the wrong type of engine. Here is how to avoid all three.
Mistake 1: Buying Too Small
The #1 complaint we hear is "it cannot start my AC." A portable generator rated at 2,000W running output might look enough for a fridge and lights, but an air conditioner, microwave or power tool needs 2–3 times its running wattage to start (surge wattage). If you plan to run anything with a motor, you need to look at surge watts, not running watts.
Mistake 2: Buying Too Big
The opposite mistake is buying a 7,000W generator "just in case." Portable generators over 4,000W are heavy (60–100 kg), loud, thirsty on fuel, and hard to move. If you are camping or tailgating, a 2,000–3,500W inverter generator is quiet, light and efficient. Buy for what you actually use, not what you might someday use.
Mistake 3: Wrong Fuel Type
Gasoline, propane, dual-fuel and solar generators each have different tradeoffs. Gasoline is widely available but has a short shelf life (3–6 months). Propane stores indefinitely but delivers 10–20% less power. Dual-fuel gives you flexibility but costs more upfront. Solar generators are silent but limited in power and only work if you have sunlight.
| Generator Type | Typical Power | Best For | Fuel Runtime (25%) |
|---|---|---|---|
| Inverter (gasoline) | 1,000–3,500W | Camping, tailgating, RV | 6–10 hours on 4L tank |
| Conventional open frame | 3,000–8,000W | Jobsite, home backup | 8–12 hours on 20L tank |
| Dual-fuel (gas/propane) | 3,000–7,500W | Home backup, longer storage | 8 hours gas / 24h+ propane |
| Solar (battery station) | 300–2,000W | Indoor use, camping, silent | 3–10 hours depending on load |
What You Actually Need to Run
Before you buy, make a list of everything you want to power, and separate it into "must have" and "nice to have." Then add up the running watts and the surge watts.
- Running watts: the continuous power a device draws (listed on the label or in the manual).
- Surge watts: the extra power needed to start a motor-driven device — typically 2–3x running watts for 2–3 seconds.
For example: a fridge (800W running, 2,400W surge) + a laptop (100W) + LED lights (50W) + a fan (60W) = running total 1,010W, surge peak 2,510W. So you need at least a 2,500W surge generator, which is typically rated at 3,000–3,500W continuous.
How Lucency Specifies Portable Generators
When customers tell us what they need to power, we do not just hand them a catalog. We build a load list together and match the generator to it:
- We ask you to list every device you want to run, with running and surge watts.
- We recommend the minimum generator that handles your surge load, with 20% headroom for future devices.
- We help you choose fuel type based on how and where you will use it.
- We recommend inverter generators for quiet use, conventional open frame for jobsites.
- We provide dual-voltage options (110V / 220V) for international buyers.
Frequently Asked Questions
Send us your device list — we calculate the right generator size and recommend the best fuel type and model for your use case.