Will a Generator Run the Oven, Fridge and Slow Cookers on Thanksgiving?

The turkey has been thawing in the fridge since Sunday, the pies are done, and on Wednesday night a late-November ice storm takes the power out. If a generator is sitting in the garage, the answer is mostly good news. Almost any small portable generator can keep the fridge cold and the slow cookers going. The electric oven is the hard part, and most plug-in generators can't run it. Below is what each appliance needs, why the oven is different, and how to plan the meal so dinner still happens.

01The Short Answer

The refrigerator and slow cookers are easy loads. The electric range is not. A standard range is a 240-volt appliance, and its oven alone draws roughly 2,000 to 5,000 watts while it heats. Most portable generators can't power a 240-volt range through an extension cord. Here is what each size of generator can realistically do:

• 2,000 to 3,000 watts: The fridge, two or three slow cookers and some lights, as long as you don't try to run everything at the same moment. This size covers most of a Thanksgiving dinner if the menu is planned around it.
• 5,000 to 7,500 watts: Everything above, plus a 120-volt electric roaster oven (the countertop kind that holds a whole turkey), with room for a microwave or coffee maker at times. It probably still won't run your kitchen range.
• 10,000 watts or more, with a transfer switch: This size can run a hardwired range. It needs a generator with a 240-volt, 50-amp outlet and a transfer switch installed by a licensed electrician.

Most households with a mid-size portable fall in the first two groups. The rest of this article explains how to cook a full meal there.

02What Each Appliance Draws

Generators carry two ratings. Running watts is what the generator can supply steadily. Starting watts (also called surge or peak watts) is the short extra burst it can supply when a motor kicks on. A refrigerator compressor needs that burst every time it cycles on. Heating appliances like slow cookers and roasters don't.

Typical figures from generator sizing charts and appliance listings:

• Refrigerator/freezer: about 700 running watts and 2,100 starting watts on one common chart. Many modern fridges use less: roughly 100 to 800 running watts, with a surge of 1,200 to 2,000 watts for a few seconds.
• Slow cooker: about 250 watts. Estimates run from about 100 to 450 watts depending on size and setting.
• 18-quart electric roaster oven: about 1,450 watts on most models.
• Microwave: about 1,500 watts.
• Coffee maker: about 1,200 watts.
• Electric oven: about 2,000 to 5,000 watts while heating, on 240 volts.
• 75-watt light bulb: 75 watts each.

To size a load, add the starting watts of the largest motor to the running watts of everything else. A worked example:

• Fridge surge: 2,100 W
• Two slow cookers: 500 W
• Four 75-watt lights: 300 W
• Total needed at the moment the fridge kicks on: 2,900 W

Once the compressor is running, that same setup drops to about 1,500 running watts. You need a generator whose running rating covers the steady load and whose starting rating covers the surge.

All of these numbers are general averages. Check the nameplate sticker on each appliance, usually found inside the fridge door, under a slow cooker's base or on the back of a roaster. Use those figures instead.

03The Oven Problem

A kitchen range doesn't plug into an ordinary outlet. It runs on its own 240-volt circuit, usually 40 or 50 amps. A 50-amp circuit at 240 volts works out to about 12,000 watts. With the oven and every burner on high, a range can draw something like 8,000 to 12,000 watts. That is an estimate, so check your range's nameplate for its actual rating.

Most portable generators can't supply that. Even a generator big enough for the load still has to connect to the range circuit, and there is only one safe way to do it: a transfer switch or interlock installed by a licensed electrician. A common 50-amp manual transfer switch is rated around 12,500 watts. Generators made for whole-home backup with 240-volt, 50-amp outlets are typically in the 10,000 to 12,000 watt range. Never plug a generator into a wall outlet or dryer outlet with a "suicide cord." That backfeeds power into the lines and can electrocute utility workers and neighbors.

If a transfer switch isn't in place by Thanksgiving, cook around the oven:

• Electric roaster oven. At around 1,450 watts, an 18-quart roaster cooks a turkey of about 20 to 22 pounds on a regular outlet.
• Slow cookers for stuffing, mashed potatoes, green beans, sweet potatoes and gravy.
• **Cook the turkey on Wednesday.** If storms are in the forecast, roast it while the power is on, refrigerate it, and reheat slices in a slow cooker with broth.
• Outdoor grill or turkey fryer. Use them only outside, well away from the house, and never in a garage or on a porch. Fried turkey needs extra care because hot oil and a frozen or wet bird are a dangerous mix.

04Build a Generator-Friendly Thanksgiving Menu

The trick is to stagger the loads. Heating appliances draw full power the whole time they heat, so run the big ones in shifts instead of all at once.

Keep the refrigerator plugged in all day. It protects the most food, and its load is small once the compressor is running. Put drinks, butter and anything you'll grab often in a cooler with ice so the fridge door stays shut.

A sample load list for a 2,500 to 3,000 watt generator:

• Refrigerator: 700 running watts (2,100 starting)
• Three slow cookers (stuffing, potatoes, green beans): about 750 watts
• Four lights: 300 watts
• Running total: about 1,750 watts. The surge when the fridge kicks on is about 3,150 watts, so look for a generator with a starting rating that covers it, or drop to two slow cookers.

Adding the roaster. A 1,450-watt roaster on top of that list pushes the running load to about 3,200 watts, which is beyond a small generator. Here are three options:

1. Turn off the slow cookers while the turkey roasts. Then switch them on once the turkey comes out and rests.
2. Unplug the fridge during the roasting window and keep its door closed. Keep that window well under four hours, then plug the fridge back in.
3. Use a 5,000 to 7,500 watt generator and run everything together.

Save the microwave and coffee maker for last. At 1,200 to 1,500 watts each, run them alone after dinner with the roaster off, one at a time.

Now, in October, is a good time for a practice run. Plug in the slow cookers and roaster on one ordinary weekend afternoon and see how the household's real appliances add up.

05Safety and Food Safety

Keep the generator outside and away from the house. The Consumer Product Safety Commission says to run a portable generator only outdoors, at least 20 feet from the house, with the exhaust pointed away from your home and any other building. Never run it in the house, garage, basement, crawlspace, shed or on a porch. Opening doors or windows does not provide enough ventilation. In ice or snow, keep the generator dry and stable without moving it closer to the house.

Install CO alarms. The CPSC recommends battery-operated or battery-backup carbon monoxide alarms outside sleeping areas and on every floor. If an alarm sounds, get everyone outside and call 911. If you're shopping for a generator this fall, look for a model with automatic CO shut-off, which turns the engine off when carbon monoxide builds up.

Keep the cold food safe. Keep the fridge door closed as much as possible, generator or not. USDA guidance:

• A refrigerator keeps food safe for about 4 hours without power if the door stays closed. After that, throw out perishable meat, poultry, fish, eggs and leftovers.
• A full freezer holds a safe temperature for about 48 hours (about 24 hours if half full) with the door closed.
• Food that still has ice crystals or is at or below 40°F can be refrozen or cooked.
• Fifty pounds of dry ice should hold an 18-cubic-foot full freezer for about 2 days. Don't let it touch food directly, and handle it with care.
• Never taste food to decide whether it's safe. Keep an appliance thermometer in the fridge and freezer so you have a real reading.

If you're unsure about something, the USDA Meat and Poultry Hotline is at 1-888-674-6854.

Planned this way, a modest generator, a few slow cookers and a roaster can get Thanksgiving dinner on the table even when the power is out.

Sources (15)

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