Power outage prep: power stations, generators and how to size them

Power station or generator?

• Portable power station (battery): quiet, no fumes, safe to use indoors. Good for phones, lights, Wi-Fi, a CPAP or a fridge for a few hours. Recharge from the wall, your car or solar panels. Capacity is limited, so very long outages need solar or a bigger unit.
• Gas inverter generator: runs as long as you have fuel and can power more at once, but it's loud and makes carbon monoxide, so it must run outdoors. Inverter models give cleaner power for electronics than basic open-frame generators.

How to work out the size you need

1. List what you want to keep running and find each item's watts on its label or manual.
2. Add up the watts of everything that will run at the same time. The power station's or generator's output watts must be higher than that total. Fridges, sump pumps and other motors briefly draw more when they start, so leave headroom.
3. For a power station, check capacity in watt-hours (Wh): watts × hours you want it to run. A 100-watt load for 10 hours needs about 1,000Wh, plus some extra because some energy is lost converting battery power to AC.

Generator safety: carbon monoxide kills

• Never run a generator inside your home, garage, basement, crawlspace or shed, even with doors or windows open.
• Keep it outdoors at least 20 feet from your home, and point the exhaust away from windows, doors and vents.
• Install battery-powered (or battery-backup) carbon monoxide alarms. If you feel dizzy, sick or weak, get to fresh air right away and call 911.
• Don't plug a generator into a wall outlet to power the house ("backfeeding"). It can electrocute utility workers. Use extension cords rated for the load, or have an electrician install a transfer switch.

Source: CDC carbon monoxide poisoning prevention.