When you're off the grid, generators can provide thousands of watts of electricity instantly, to run your most power-hungry appliances. Microwaves, toasters, hair dryers, and power tools can draw huge current; if you try to run them off of your battery bank, the current draw quickly depletes your battery bank, stresses your wiring, requires expensive inverters, and can damage your batteries.
Generators are rated by their peak watt capacity, and generally start at about 1000W. The peak rating is for start-up watts (many items pull more power when they first start up, and then settle down to a lower consumption); a 1000W generator will generally be capable of maintaining 800-900W. These small generators are enough to run:
- microwave (800W)
- house battery charger
- television (300W)
- chargers for electronics (laptops, phones, etc - all under 100W)
2000W generators can handle most appliances:
- hair dryer (1600W)
- toaster (1000W) or toaster oven (1800W)
- large coffee maker (1200W)
- circular saw (1000W)
- small air compressor (1600W)
Overall recommendation: The Yamaha EF2000iS 2000W portable generator, or its almost-identical competitor, the Honda EU2000i. These generators run about $1000, which is a few hundred more than some other similar-looking 2000W generators, but they're known for their durability, fuel economy, and perhaps most importantly, their quiet running. Reviews consistently rave about how quiet they are, and many people have found that placing them 40 or 50 feet away from their campsite is far enough to eliminate any noise at all. Don't waste your money buying cheap imitations - they've been reported to break down frequently, have trouble starting, and run much louder. If you don't need much power, you can save $200 (and use less fuel) by picking up the smaller Yamaha EF1000iS 1000W generator.
Portable gasoline: see our overall recommendation above, the Yamaha EF2000iS.
Built-in propane: if you're planning on building your generator into your camper (generally underneath), the Cummins Onan line of propane generators are considered the standard. They start at about $2000, but at the price provide 2500W of power while consuming 0.2 to 0.6 gallons of propane an hour. A 20lb propane tank holds almost 5 gallons of propane, giving you a full day's worth of power on a tank. Generators generally won't be run constantly, but instead are fired up to recharge a battery bank, or to run a high-draw appliance for short periods. With this type of useage, it's likely that a tank of propane will last you a week or more.