Ever been in a major blackout? The last time it happened to us Mother Nature dropped three feet of snow on our high-plains farm and the electricity was out for five days. It was my job to figure out how to heat two mobile homes and pump water to 40 horses, all with a small and temperamental Coleman generator. Fortunately, I had a roll of Romex on hand and was able to run hastily wired isolated circuits from both furnaces and the well pump to the generator outside. As if to accentuate the travails of a really trying week, the generator’s pull starter gave out on the fifth day. Two hours later the grid power came back on. We were lucky.

Since that character-building experience, we’ve moved to the mountains and off the grid and haven’t had to endure a power outage, large or small, in over 10 years. It’s one of the more satisfying advantages of off-grid living: being perpetually prepared to keep the house warm and the lights on. But you probably don’t have the need for a large solar array and an all-business wind turbine, tied into a huge bank of batteries and a backup generator. Why should you? It’s an enormous investment if you’re already hooked into the electrical grid and your primary rationale for having a system is to supply backup power during blackouts.

On the other hand, massive and lengthy blackouts are becoming more common and it’s only a matter of time before Mother Nature singles you out for a character-building experience of your own. So the question is: how can you protect yourself and your family from a possibly life-threatening scenario without mortgaging your house or decimating your kids’ college fund?

Generators: Choosing a personal power plant

Honda offers a nice line of quiet, sturdy, all-purpose home generators.

The most obvious answer is to buy a gasoline-, diesel-, or propane-fired generator that you can plug your house into whenever the grid goes south. Thousands of homeowners have done this in blackout-prone areas. With enough fuel on hand, a backup generator can see you through almost any power failure of non-biblical proportions.

But before you run out and buy a generator you will first need to determine which loads you’ll absolutely need to keep running during a sustained blackout. Usually this is the furnace or boiler, the refrigerator and range, the well pump and a few lights. If all these things were running at once, how many kilowatts of electricity would they consume? Once you answer this question—either by reading each appliance’s amperage ratings or, better yet, taking direct measurements with a watt meter—you can size your generator.

There are a few things to keep in mind when choosing a generator. Most popular home generators are designed with their power output distributed to several different circuits. For the purpose of running your critical loads, however, you will have to be certain that you can get all the power you need from one circuit. This will be 25 or 30 amps at 240 volts for the most popular 6- to 10-kW generators. Should you require more power, look for a stationary generator built specifically for home backup applications.

Because air holds less oxygen the higher up you go, generators lose power with altitude. For this reason you should conservatively estimate that any generator will lose three to four percent of its rated output for every 1,000 feet above sea level. This may not sound like much, but it adds up quickly. Where we live at 7,000 feet altitude, our 6.5 kW Honda is only capable of about 4.8 kW of sustained output.

And finally, bear in mind that fuel type is important. Gasoline-fired generators need to be manually choked before starting and diesels can be downright cantankerous in cold weather. Propane-fired generators are the easiest to start in any weather and are the only viable choice if you decide on a deluxe setup in which the generator is wired to start automatically when the grid goes down. Besides, with your generator hooked directly into your home’s propane tank, you’ll never have to worry about refueling or running out of fuel.

Not sure where to start looking? Honda offers a nice line of quiet, sturdy, all-purpose home generators. They’re dependable machines that you can wheel out of your garage or toolshed whenever the lights go out, and you can easily connect them to the house via a heavy-duty extension cord.

If you’d rather go all out with a hard-wired stationary generator, take a look at the Kohler line. Kohler generators each come with their own all-weather enclosure and they’re designed to be set on a concrete pad beside the house. And when wired into a Kohler transfer switch, they can be programmed for automatic start when the grid fails and automatic shutdown once it comes back on.

There are many other manufacturers of dependable generators; I just happen to have had good experiences with Honda and Kohler. Whichever generator you choose, choose as if your life depends on it. Because it might.

Transfer switches: Where do I plug this thing in, anyway?

If you are at all familiar with your home’s wiring, you’ve probably noticed that there isn’t a neat little electrical box anywhere inside or outside your house with “generator inlet” or “auxiliary AC in” emblazoned on the cover. There’s a very good reason for this: it is exceedingly dangerous to plug a generator directly into your home’s grid-connected wiring. It’s also illegal. Just the same, it hasn’t stopped some gung-ho types from installing their own jury-rigged grid connections, often with disastrous results. Without safely isolating your generator’s output from the power grid, you run several risks. When, for instance, the grid comes back on while your generator is hooked into it and running (and you know sooner or later it will), the grid current—which will be out of phase and flowing in the wrong direction—can, at the very least, burn up your generator’s fragile windings.

But frying a generator is still preferable to turning it into a deadly weapon, something that you might do if you backfeed power into the grid when the grid is down. The high-voltage current from your generator will not stop at your house. It will instead follow every circuit available to it. You could easily electrocute a power company worker or even your neighbor, either of whom might be unwittingly exposed to hot wiring they assumed was not energized.

Kohler offers a hard-wired stationary generator designed to be set on a concrete pad beside the house.

So when I say you’ll need to install a transfer switch, believe me. You do.

Transfer switches are all designed with a single purpose: to make it impossible for the outputs of your generator and the power grid to ever run through the same circuits at the same time. Depending on the type and model, a transfer switch can be located either inside or outside your house and, as noted above, can be activated either manually or automatically. Many, but not all, have built-in critical-loads circuitry. If the switch you choose does not, you can, without going to too much trouble, isolate your critical loads from the main house panel into a separate sub-panel which will then be routed through the transfer switch. In that way (providing you’ve sized your generator to your load requirements), you won’t run the risk of drawing more power than your generator can handily supply

Conceptually, it’s all pretty straightforward. The devil, as they say, is in the details, and when it becomes the National Electrical Code, it’s all details. Is this anything you can do yourself? Sure, if you’ve got the know-how to wire a house well enough to pass an electrical inspection. Otherwise, you’d be well advised to call an electrician. When it comes to electricity, nothing takes the place of experience. At the very least it may save you a few gray hairs.

Would you like to add batteries to your backup system so you don’t have to listen to a generator day and night? And maybe even a renewable-energy component to charge the batteries? Stay tuned for Part 2.