Choosing a home generator starts with listing the appliances you must run, then matching total wattage to a unit sized for those loads.
When the power goes out, the difference between a good night and a bad one often comes down to whether you planned ahead. The task isn’t as hard as it sounds. You don’t need to power your whole house; you need to power what matters. Getting that right means thinking through your needs before you shop, understanding the two main generator types, and taking carbon monoxide safety seriously.
Start With Your Real Power Needs
The first step in sizing a generator is knowing what you actually need to run. Consumer Reports recommends listing the devices you’ll need during an outage and adding up their wattages. This total gives you the running capacity you’re shopping for.
Make that list now, not after the storm. Walk through your home and jot down the essentials:
- Refrigerator and freezer
- Well pump or sump pump
- Furnace blower or space heaters
- Lights and phone chargers
- Medical devices or CPAP
Check each device’s label for its wattage. Add them up. Then remember that motors draw extra power when they start — a fridge rated at 700 running watts might need 2,000 watts to kick on. If your list includes a well pump, account for that startup surge. Aim for a generator that handles your total running watts plus the single largest startup spike.
Portable or Standby: Which Type Fits Your Situation?
Your use case decides the generator class. Portable generators are temporary, run on gas or propane, and need manual setup outside each time you use them. Whole-home standby systems run on natural gas, are wired into your electrical panel, and start automatically when the power drops.
Portable generators fit most households on a budget or those facing outages a few times a year. They cost far less and store easily, but they demand effort: wheel it out, connect it, and never run one indoors.
Standby generators deliver true whole-home comfort. They sense the outage, start themselves, and handle heavy loads like central air. That convenience comes with professional installation and a price tag several times higher than a portable unit.
Most homeowners who want to keep the essentials running — fridge, heat, lights, and a phone charged — will find a quality portable generator plenty. If you depend on electricity for medical equipment or want seamless power during a multi-day outage, a standby system is worth the investment.
Safety Features That Should Be Non-Negotiable
You cannot afford to skip safety here. The CPSC warns that generator exhaust can kill in minutes, and — so you do not operate these indoors ever.
When you compare models, prioritize CO shut-off features. The CPSC recommends portable generators certified to PGMA G300-2023 and UL 2201-2023, which include carbon monoxide safety technologies. UL 2201-certified models go further with reduced CO emissions. Look for these certifications on the box. Also plan to install battery-operated CO alarms on every level of your home and outside sleeping areas; test them monthly.
For placement, run the generator outside only — never in a garage, basement, crawlspace, or porch, even with the door open. The CPSC says to keep it at least 20 feet from the house, with exhaust directed away from doors, windows, and vents. Leave 3 to 4 feet of clear space on all sides and above for ventilation.
Matching a Generator to Your Load: A Quick Reference
| Typical Home Load | Running Watts | Good Generator Size |
|---|---|---|
| Fridge, lights, phone chargers | 700–1,200 | 2,000–3,000 |
| Above plus furnace and sump pump | 1,500–2,500 | 3,000–5,000 |
| Most of the home minus central AC | 3,000–5,000 | 5,000–7,500 |
| Whole home with electric appliances | 5,000+ | Standby system |
Once you know your wattage range, compare models on runtime — how long a full tank runs at half load is the number that matters. Also check the fuel type: gas is easiest to find, propane stores longer and never goes stale the way gas does. If you’re working within a budget, our tested roundup of the best cheap generator for home use can point you toward solid value picks.
Common Mistakes That Cost People Everything
Most generator tragedies share a pattern. Running the unit indoors, in a garage, or on a porch with the door cracked is the biggest one. Open windows and doors do nothing to prevent CO buildup. Another mistake is ignoring the faint headache or dizziness that comes with CO exposure — those symptoms, plus weakness, nausea, and confusion, mean get outside now and call 911.
Skimping on placement is just as common. The 20-foot rule exists because exhaust drifts. And don’t skip the owner’s manual; each model has specific maintenance requirements and wet-weather precautions that keep the unit reliable and safe.
References & Sources
- Consumer Reports. “Generator Buying Guide.” Recommends listing devices and totaling wattages.
- U.S. Consumer Product Safety Commission. “Generators and Engine-Driven Tools.” Details CO hazards, 20-foot placement, and certified safety standards.
- Centers for Disease Control and Prevention. “Generator Safety Fact Sheet.” Explains CO poisoning symptoms and response steps.