Answers to generator questions from our Facebook fans

The widespread power outages caused by Superstorm Sandy resulted in many homeowners using generators for the first time. Consumer Reports heard from some of these novices on our Facebook page where we asked them about their experiences restoring temporary power to their homes. The biggest complaint was that gas was hard to find. Given that, some readers asked about alternative fuel sources as well as how to safely install and use a generator. Here's some answers from our experts.

Types of fuel
Q: On our Facebook page, Chris Prytko asked: "There are so many styles and fuel sources. Gas, diesel, natural gas, propane, tri-fuel ... where does a guy start!"
A: Stationary generators, which run on natural gas or propane, are the best option for prolonged outages like the one caused by Sandy and the reason more people are considering a generator in the first place. Propane and especially a direct natural-gas line are easy and safe, compared to the need to store and preserve gallons of highly volatile gasoline (figure on some eight to 22 gallons per day), which is often unavailable during an outage. Natural gas lets your generator run indefinitely, while a 250-gallon propane tank can provide more than two weeks of power.

Power delivery
Q. Cynthia Finley told us she bought a new 5,000-watt Coleman generator to replace an old 5,000-watt generator that finally bit the dust. "The new generator does not work as well as the old one, we are not able to power as much of the house as before. Does not make very much sense to me!"
A. It's possible that your home's power demands may have changed—possibly with a large-screen plasma TV or another new, power-draining device. And that isn't always obvious when you replace old appliances. Or, the new generator may not be as good at meeting the higher, surge requirements of refrigerators and other motorized items that cycle on and off; better ones are up to that task without faltering or stalling. When Consumer Reports tests generators, it measures both the delivery and the quality of the power.

Maintenance
Q. Rich Handel told us that, "We used a portable Yamaha generator that we borrowed from a friend for a couple of storms in the past and then ended up buying from him during the snowstorm last October. I always top it off with stabilized gas when I'm finished with it. It started up great and served us for three days while the power was out. It's also very quiet compared to most generators."
A. Words to the wise from Rich. The best and easiest way to store a portable generator is to add a stabilizer to the fuel in the tank (presuming it's no more than a month old) and run it dry—or at least for enough time so that the stabilized fuel coats all of the critical carburetor and fuel-system parts. Stabilized fuel (Sta-bil is one major brand) typically lasts roughly a year—versus as little as a month or two—before it oxidizes and leaves damaging deposits in the system. You should also unscrew the spark plug and spray some engine fogging oil into the cylinder; then reinsert the plug. The fogging oil (available at auto-parts and power-equipment stores) helps keep the cylinder walls from corroding, which can make the piston rings stick and cause undue wear.

Transfer switches
Q. Mark Strzegowski explains, "My setup—Coleman 5,000-watt, external power inlet, panel-mounted interlock kit to prevent backfeeding—allows me to feed power to any circuit in the house. Runs furnace, lights, TV, refrigerators, water well and the coffeemaker! (Only the AC, electric dryer and dishwasher are offline in an outage.)"
A. As Mark points out, a transfer switch (about $500 to $900 installed) that connects a generator directly to your home's electrical panel is the best and safest way to use a generator. You avoid the hassle and risks of running extension cords between the generator and the items you're powering. And you eliminate the risk to the utility worker as regular power returns, since you aren't backfeeding generated current into the grid.

How big and how much?
Q. Robert LeBlanc asks, "We have 200 amp service and would like something powerful enough to run just about everything. Do we need a 20,000-watt unit? What's the approximate cost of materials and install? Is a permit required?"
A. You can easily pay $10,000 or more for generators that produce upwards of 10,000 watts. But generators like the 5,000 to 7,000-watt models we recently tested can power most essentials, with the exception of a central air conditioner and electric range, for about $2,000 plus installation. With the transfer switch, figure on about $1,500 to get one installed, bringing the cost to about $3,500 to $4,500. Permits are typically required. That's one more reason to look into installing a stationary generator before the next disaster.

Solar powered generators?
A. Bree Weasner wanted to know, "Has anyone researched or had experience with solar generators? I don't see any mention of these types here, and am very interested to learn more, but I just don't know where to start! Lines at the gas station are still frightening!"
Q. No, we haven't tested solar generators but as with solar mowers, they're on our list. We've had mixed results in our tests of roof-mounted solar power systems for the home, namely home water heaters. So we'll see.

Wattage requirements
Q. Robert LeBlanc also had some qualms about an inverter he tried, saying, "The 600-watt inverter from WalMart couldn't even power a coffeemaker without immediately tripping the overload."
A. It's helpful to familiarize yourself with the wattage an appliance needs before investing in any alternate power source. A refrigerator often requires about 600 watts, a portable heater 1,500 watts, a window air conditioner 1,000 watts, and lights 60 to 200 watts. According to our wattage calculator, a coffeemaker requires more than 1,000 watts, which is why it was no match for your inverter. To see what size generator you need to power your home's essentials, check the wattage requirements section of our generator buying guide.

—Bob Markovich