Generators you can depend on in a storm

Power-zapping storms like Superstorm Sandy have helped generators join hardwood floors and granite countertops on homeowners' wish lists. Our tests of almost 30 generators include a 7,000-watt portable that can power most needs for just $600. But even this one can't match a brawnier stationary model if you want it all.

Stationary generators install permanently and can switch on automatically when needed. That helps explain why stationary sales are growing fastest.The newly tested Kohler 14RESAL, $3,700, topped two others that deliver more than 11,000 watts—enough for the usual essentials plus a central air conditioner and more.

Our tests also include a new Generac portable generator that isn't affected by gasoline shortages, along with an ultra-quiet new Honda. But less noise and friendlier fueling can come at a hefty price. And one new Briggs & Stratton stationary generator could put appliances at risk when the lights go out. Here are the details.

A propane portable falls short. Sealed canisters with a long shelf life make propane easier to store than gasoline. The Generac LP5500, $800, is one of the few portable generators that run on propane without a conversion kit (about $200). But each 20-pound tank yields relatively little run time. And while a wheel-style "Power Dial" puts key controls in one place, its starting procedure was not intuitive.

Peace at a price. Inverter technology that varies engine speed with the load made the portable Honda EU6500iS1T about half as noisy as other generators. Freedom from voltage spikes and dips that can overheat appliances and electronics also helped the Honda ace our power-quality tests. But at $4,500, it's costlier than the largest stationary models we tested. Better surge wattage for items that cycle on and off also put many portables above it in our power-delivery tests.

Voltage for two plummeted. All of the stationary generators met their advertised power claims, including the ones for surge wattage. But voltage dropped nearly as much for the stationary $2,200 Briggs & Stratton 40445 as it did for the $1,200 Generac XG7000E 5798 portable.

Stationary generators were also a hit with subscribers we surveyed after Superstorm Sandy, especially for fueling: Only 9 percent who owned one complained about closed gas stations and long waits compared with nearly 70 percent of portable owners. Here's what else to consider.

Include a transfer switch. About $500 to $900 installed, it safely connects a generator to your circuit panel (letting you power hard-wired appliances) and avoids the risk and hassle of extension cords.

Plan ahead for fuel. Most portables use about 12 to 20 gallons of gasoline a day or four to eight 20-pound propane tanks. For stationary models, figure on 8 to 15 days for a 250-gallon propane tank. And be sure any gasoline is stored away from the house and preserved with a fuel stabilizer.

Look for smart features. All but the portable Troy-Bilt 6000 and Briggs & Stratton 30468 turn themselves off when engine oil is low. A fuel shutoff on the gasoline models also makes it easier to run the engine dry before storage.

Try rolling it. Portables we tested weigh up to 350 pounds with fuel, but front-heavy models make rolling easier using the handle; small wheels and poor weight balance made moving the low-priced Predator 68530 a wrestling match.