I was happy to see an article attempting to help readers understand hybrids and plug-in hybrids in the widely read magazine Condé Nast Traveler last week. These vehicles have the potential to dramatically reduce petroleum consumption, but of course the only way they’ll catch on is if people know about them.

I wasn’t as happy after I read the article.

No, today’s hybrids cannot drive 30 miles on electricity alone. They’re designed to go only a couple of miles before the gasoline engine kicks on.

No, we do not need a new kind of battery to make plug-in hybrids work. Kits exist today for converting conventional hybrids into plug-in hybrids (it can be done in about two hours). The major automakers have higher standards for plug-in batteries, but GM engineers say that they already have the batteries they need. The challenge now is incorporating them into big battery packs. But that’s been done before with other batteries, and GM engineers say that they’ll have the new packs ready for testing this year. By 2010, GM aims to have the packs in production vehicles. (See “Electric Cars 2.0.”)

And no, plug-in hybrids won’t cause blackouts. There’s plenty of excess electricity capacity at night, when most people will be plugging them in. Indeed, eventually plug-in hybrids could be used to prevent blackouts. (See “How Plug-in Hybrids Will Save the Grid.”)

But here’s the biggest problem with the article. It defines a plug-in hybrid as “a hybrid you have to recharge just like an electric car.” This is exactly wrong, and it is just what automakers are concerned that people will think. One reason people haven’t adopted electric cars is because their limited range and long charging times make long trips difficult. (One electric-car champion boasted to me that he takes road trips all the time in his electric car. But he has to hunt down RV parks and take two-hour breaks along the way for recharging.) The whole point of a plug-in hybrid is to get around this problem.

Plugging in a plug-in hybrid is strictly optional. If you plug it in to recharge the battery, you can drive to work and back using electricity alone, which will save you money and reduce carbon emissions. (See “Plug-in Hybrids Get Green Grades.”) You can also make the first miles of a road trip using electricity alone. But if you prefer not to plug it in, or if an outlet isn’t handy, the car simply runs on gasoline. Indeed, a plug-in hybrid can get much better range than a conventional gasoline car because it uses gasoline more efficiently. GM’s Volt plug-in is to have a 600-mile range using gasoline, with 40 miles more if you happen to plug it in.