Tips for Using Emergency Generators

A standby generator, unlike a portable generator, is permanently connected to your electrical system and goes on automatically when the power goes out. Standby generators can run on propane or natural gas, eliminating the need to monitor the fuel. And they're quieter. You can buy one large enough to power everything in your house, or you can buy a smaller unit and choose the most critical circuits to power. Standby generators start at about $1,800, plus installation. (And they do need to be installed by a pro.)

The difference in cost between a portable generator and a standby unit may not be as great as you think. Remember, a portable unit requires either expensive extension cords or a transfer switch. Standby units can run on less expensive natural gas, which will save you money in the long run.
Photo provided by Kohler

When it comes to portable generators and ease of use, liquid propane (LP) sure beats gasoline. Gasoline is a handy fuel, but it's not without problems. Storing enough gasoline to get you through a several-day power outage requires constant vigilance. First you have to buy several 5-gallon gas containers and find a safe place to store them. Then you have to add stabilizer and ideally replace the gas after several months to make sure it's still fresh when you need it.

Propane-powered portable generators solve these problems and more. You can store and use liquid propane (LP) indefinitely (it doesn't go bad). Refueling is simple and safe; just replace the propane tank with a full one. And you don't have to worry about the carburetor on your generator getting gummed up with old gasoline.
Photo provided by Generac

You may find a great deal on a generator by shopping online. But what will you do if you can't get it serviced locally? Sometimes it's worth spending a little extra to buy from a local dealer. Parts will be available, and the dealer will be familiar with maintenance and repair procedures for your model. So before you buy a generator, make sure there's someone nearby who can provide parts and service.

A 5,500-watt generator will run about eight hours on 5 gallons of gasoline, so gas management is critical if you want to be prepared for an extended power outage. That may mean running your generator for shorter periods and coasting on things like refrigeration.

Having several filled 5-gallon gas cans available is prudent, but you'll need to add stabilizer to extend the shelf life. Even then, after six months or so you should pour it into your car's gas tank and refill the cans with fresh fuel. The generator itself should be run dry for storage or filled with stabilized fuel. That fuel should be replaced every six months as well.

Computers, TVs and many modern appliances contain sensitive electronics that can be damaged by the “dirty” power produced by less expensive generators. Inverter-type generators provide the cleanest power but are very expensive, especially in sizes large enough to power a house. But for a little extra money, you can buy generators with power conditioning that provides cleaner power. Total Harmonic Distortion (THD) is a way to measure the quality of electricity from a generator. Look for a generator with a THD of less than 5 percent to safely operate most electronics.

One problem with portable generators is the noise that you—and your neighbors—have to put up with. You can compare decibel ratings to find quieter models, but keep in mind that there's no industry standard, so you may be comparing apples and oranges. Standby generators are quieter, and for a stiff premium you can buy a really quiet portable generator like the 6,500-watt Honda shown here. It costs $4,500.
Photo provided by Honda

Your first step in adding backup power is deciding what you need to keep running when the electricity goes out. This determines the size (wattage) of the generator you'll need. Look for a label on each appliance that contains information such as wattage, model number and the year it was made. Some labels are right inside the door; others are on the back. Write down the item and how much wattage it uses. Be sure to include essential items, like refrigerators, freezers, a well pump if you have one, and a sump pump if your basement could flood. You can go a few hours or even days without an oven (use the microwave instead) and an air conditioner—they use a lot of power and would require you to buy a much bigger generator.

Add together the items' wattages, then multiply that number by 1.5 (appliances need the extra power to start up). That's the minimum wattage needed for your generator.

Every generator lists two capacity ratings. The first is “rated” or “continuous” watts. That's the maximum power the generator will put out on an extended basis. And it's the only rating you should rely on when buying a generator. The higher “maximum” or “starting” rating refers to how much extra power the generator can put out for a few seconds when an electric motor—like the one in your fridge or furnace—starts up. If you buy a generator based on the higher rating and think you can run it at that level, think again. It will work for a little while. But by the end of the day, your new generator will be a molten mass of yard art, and you'll be out shopping for a replacement.

Most new generators need their first oil change after just 25 hours. Beyond that, you'll have to dump the old stuff and refill every 50 or 60 hours. So you need to store up enough oil and factory filters to last a few days (at least!). Running around town searching for the right oil and filter is the last thing you want to be doing right after a big storm.

Generator fuel tanks are always on top of the engine so they can “gravity feed” gas to the carburetor. But that setup can quickly turn into a disaster if you spill gas when refueling a hot generator. Think about it—spilled gas on a hot engine, and you're standing there holding a gas can. Talk about an inferno! It's no wonder generators (and owners) go up in flames every year from that mistake. You can survive without power for a measly 15 minutes, so let the engine cool before you pour. Then strap on an LED head lamp so you can actually see what you're doing. Pour slowly and avoid filling the tank to the brim.

Stale fuel is the No. 1 cause of generator starting problems. Manufacturers advise adding fuel stabilizer to the gas to minimize fuel breakdown, varnish and gum buildup. But it's no guarantee against problems. Repair shops recommend emptying the fuel tank and the carburetor once you're past storm season. If your carburetor has a drain, wait for the engine to cool before draining. If not, empty the tank and then run the generator until it's out of gas. Always use fresh, stabilized gas in your generator.

The only thing worse than the rumbling sound of an engine outside your bedroom window is the sound of silence after someone steals your expensive generator. Combine security and electrical safety by digging a hole and sinking a grounding rod and an eye bolt in concrete. Encase the whole thing in 4-in. ABS or PVC drainpipe, with a screw-on cleanout fitting. Spray-paint the lid green so it blends in with your lawn. If you don't want to sink a permanent concrete pier, at least screw in ground anchors to secure the chain.