Shopping for a plug-in car is a little different from the search for a traditional gas-powered vehicle. If you haven't done research into electric or plug-in hybrid cars, the terminology can be mystifying. There's kilowatt-hours, charging and range. And what's up with the tax credits?

But shopping for a plug-in car doesn't have to be a painful experience. Although some aspects may be different, buying a plug-in car has a lot in common with traditional car shopping. And you wouldn't do that without knowing the basics of the models that caught your eye.

Shopping for an EV, such as the 2017 Hyundai Ioniq Electric, requires a bit of research, not an engineering degree.

Edmunds visitors save an average of $2879 off their new car. How much can you save?

Being ahead of the knowledge curve at the dealership makes the buying process easier for you and helps the dealership, too, particularly if they don't sell a lot of plug-in vehicles. (EVs and plug-in hybrids make up less than 1 percent of new vehicle sales in the U.S.) Your savviness could help the dealership be more knowledgeable for the next customer.

Be in the Know

To help you make shopping easier, we plumbed our own knowledge, talked to advocates for plug-in cars and spent some time with car salespeople who are successful in selling them. We asked them what shoppers want to know and what the typical electric-car shopper could bring to the showroom to make the buying experience run smoothly, even at dealerships with little electric car experience.

Here are the nine best ways to select and purchase or lease a plug-in car.

1. Research the Cars

The first thing in shopping for a plug-in car, as in shopping for any car, is to know what you want, or to at least have a couple of candidates on your shopping list. If you haven't already decided whether a plug-in electric car will work for you, this Edmunds article on making the right plug-in vehicle choice is the place to start.

For a look at the electric and plug-in hybrid electric models currently in the market, you can visit manufacturer websites or check Edmunds for reviews of such popular EVs and plug-in hybrids as the BMW i3 and i8, Chevrolet Volt, Ford Fusion Energi, Nissan Leaf, Tesla Model S and Model X, and Toyota Prius Prime. Other good sources include the federal Energy Department's interactive Advanced Cars and Fuels tool, which lets you do side-by-side comparisons of the various plug-in electric cars. For a very deep dive into plug-in vehicles, including delivery vans, buses and motorcycles, there's Plug In America's Plug-in Car Tracker.

2. Understand That Electric Car Range Will Vary

The federal Environmental Protection Agency estimates electric car range, and the all-electric range of plug-in hybrid and pure electric cars are widely used to help advertise the cars. But high-speed driving or extreme cold or heat can significantly reduce the claimed range. You need to know how and where you drive to know what range you can realistically expect. In describing the car to you, the salesperson may simply be relying on the federal estimates or manufacturer's claims and nothing more.

All-electric range for plug-in hybrid cars varies by model. Currently it is from 10 miles to about 40 miles on a single charge before the internal combustion engine or generator takes over. All then revert to conventional hybrid mode, with the electric drive assisting the gasoline engine.

Pure electric cars in the market also have varying range, which has improved in the last couple years. They go from around 60 miles per charge up to newer entrants to the market, such as the Hyundai Ioniq Electric at 124 miles and the Chevrolet Bolt at around 200 miles. At the top are the Tesla Models S and X, with a range of around 300 miles, depending on their trim levels. Most EVs, though, are in the 80- to 110-mile range category.

Commuters who spend most of their drive at highway speeds, however, typically will realize only 80-90 percent of the estimated range. It takes a lot of energy to move a car at high speeds as wind resistance increases.

If you routinely drive in extreme heat or cold, you'll also see an impact on range. The ambient temperature can affect the battery's ability to store and release energy. Testing by the AAA showed that a battery good for 105 miles of range at a steady 75 degrees Fahrenheit delivered only 43 miles at 20 degrees. At 95 degrees, range was 69 miles.

3. Find the Incentives for the Vehicles on Your List

It's possible that the salesperson you'll be dealing with won't know about all of the available incentives for a plug-in electric car. So you should.

The federal incentive is fairly easy. It's an income tax credit, not a rebate. If you finance the car, you'll do so on the price before the tax credit. The credit is based on battery size and vehicle range. The Department of Energy's fueleconomy.gov site carries a fairly up-to-date list of which plug-in electric cars qualify for what.

The basic rule of thumb for EV federal tax credits is that all-electric vehicles have large enough batteries to qualify for the maximum benefit, which is a tax credit of up to $7,500. It is applicable only in the year in which you buy and can only be used to offset your federal income taxes. There's no cash refund if your tax bill is less than the incentive.

Federal plug-in vehicle credits range from as little as $3,667 to as much as $7,500. Again, these are maximums, dependent on the size of your federal tax bill.

State and local incentives include reduced electricity rates, free parking, carpool lane use, help buying home chargers, and cash rebates and tax credits for vehicles. But not all states and communities offer incentives. They also change frequently. A good source is Plug In America's easy-to-use interactive state and federal incentives map.

You should also call your city hall to see if you are eligible for local benefits that aren't on the National Council or Plug In America lists. Check with your local electric utility company to see what kinds of help it might be offering. Utility company websites often list special-rate programs for people who own a plug-in car.

Your car salesperson should be able to tell you about any applicable manufacturer incentives. But you also can find them for yourself by checking out Edmunds' incentives and rebates center or by visiting the manufacturer's website for the model you're considering.

4. Learn About the Kilowatt-Hour

You don't have to understand the mysteries of electricity to shop for a plug-in car, but at the very least you'll want to understand kilowatt-hours (abbreviated as kWh). This is the basic unit of measurement on your home electricity bill. Plug-in cars rely on batteries for some or all of their power, and battery capacity is measured in kilowatt-hours, not those familiar gallons that help us determine the fuel efficiency and range of conventional cars. Don't count on every car salesperson to be a kilowatt-hour expert.

When we're driving conventional cars, we measure fuel economy in miles per gallon. But for plug-in cars, it's miles per kWh. It takes 33.7 kWh of electricity to equal the energy contained in one gallon of gas. Once you understand that, you can figure out the efficiency of the cars you're considering.

The 30-kWh battery in a 2017 Nissan Leaf, for instance, holds the energy equivalent of just under a gallon of gas. It provides 107 miles of travel. That's the equivalent of 112 miles per gallon in combined city/highway driving in a gasoline-fueled car.

5. Get Familiar With the Basics of Plug-in Car Chargers

The plug-in car you buy should dictate the type of charging station you purchase, but there are variables to consider.

Plug-in hybrid cars with relatively small batteries and all-electric range under 15 miles, such as Toyota's 2014 and 2015 Prius Plug-In models, can get by with overnight charging from a common 110-volt grounded wall socket. Those with extended all-electric range, such as the Ford C-Max Energi (19 miles), Ford Fusion Energi (20 miles) and Chevrolet Volt (50 miles), will be easier to live with if you can charge them on what's called a Level 2 unit. It provides power at 240 volts. Level 2 charging enables most plug-in hybrid cars to be recharged in four hours or less.

Level 3 chargers are also known as DC chargers or quick chargers. These are high-powered devices usually installed in dealerships and at convenient retail and other locations along well-traveled highways. They can provide an 80 percent charge of a depleted electric car battery in about 30 minutes and typically are used by electric-car owners when they're traveling. Level 3 charging isn't an option for plug-in hybrid cars. Automakers say it costs too much to equip them for such charging and that their smaller batteries simply don't need it.

If you decide that for daily use a Level 2 station is for you and you own or rent a residence or business in which you can install one, check with your city or county to find out what permits are needed and what they'll cost.

Talk to an electrician about the capacity of the electrical service that's located where you'll be installing the station. In most modern buildings, the service should be sufficient. In older buildings, you might have to upgrade the electrical service, which can cost from several hundred to several thousand dollars.

While some dealerships may have connections with local electricians and charging system suppliers, others won't. Checking all this out in advance will help you decide which plug-in car is right for you.

6. Know Your Charger Choices

Most dealerships that sell plug-in cars will be able to recommend a charging station, which is more formally known as "electric vehicle service equipment." Carmakers often have deals with electric vehicle service equipment suppliers for sales, financing and installation of a particular brand or brands. These often are good deals that can save you time and money by packaging the charging station and its installation into a single bundle.

But you aren't tied to the station that the dealership might want to sell you, and if you shop around in advance, you'll be able to compare prices for a station that the dealership offers.

These days, there are a large number of service equipment suppliers, offering everything from bare-bones charging stations to ones that are elaborately networked. These more sophisticated stations can communicate with your utility to provide power at the lowest possible cost and let you know when your vehicle is charged and how much juice it took.

Electric vehicle service units also come in varying capacities. They should be matched with the capacity of the vehicle's onboard charger to send juice to the battery.

A good source for home charger information is GoElectricDrive.org, a site maintained by the Electric Drive Transportation Association.

7. Get Up to Speed on On-the-Go Charging

Dealerships are in the business of selling cars, and most are not well versed in the availability of on-the-road charging. An exception may be Tesla, which is building out a national network of supercharger stations and publicizes it as a selling point for its cars. (Those stations are no longer free for all Tesla owners, just those who bought before January 1, 2017. Anyone buying after that date gets 400 kWh of charging credits for their Model S or Model X.)

For public and commercial charging station information, one of the best sources we've found is PlugInCars.com. The site offers a charging network guide that lists all the major national and regional networks and the fees and rules of use. There's also contact information to help you find specific charging station locations for each network.

Additionally, charging-station providers and independent plug-in car support groups offer a number of smartphone applications that not only locate and direct you to chargers but in some cases enable you to reserve a time to use one.

The PlugShare app even lists the home stations of the cooperative's members who are willing to share their Level 1 and Level 2 plugs with fellow electric-car drivers who need an emergency charge while on the road. These apps and in-car charger locator systems are especially valuable when traveling. They can mean the difference between finding a charger and waiting hours on the roadside for a tow.

8. Pay Close Attention to the "Info" Part of the Infotainment System

Insist on getting a thorough training session on the in-vehicle and smartphone features of the cars you are considering. In plug-in electric cars, these systems all have features that enable you to monitor the battery, charging and energy systems. Being able to use these features proficiently can help improve vehicle range and fuel efficiency. Also, most plug-in vehicles now have navigation systems that show the location of charging stations, distance to them and driving directions. Some will even tell you if a station is in use.

9. Use These Electric Test-Drive Tricks

  • Keep the windows up and radio and fans off during your test drive. Cars running in all-electric mode don't have engine noises to muffle other sounds, so the in-cabin noises you hear during the test drive will let you know just how quiet the car will be if you decide to take it home.
  • If you're testing plug-in hybrid cars, remember that they shuttle between all-electric and gas-only operation. Check the smoothness of the transition during your test drive to make sure it is acceptable to you. Some are smoother than others.
  • Be especially attentive to how the brakes feel. Use them often and try both soft and hard braking during the test drive. Some drivers have trouble adjusting to the feel of regenerative braking.
  • When doing your walk-around of the car, check out the location of the charging plug port. Make sure you'll be able to locate your home charging station so the cord will reach the port on the vehicle you'll lease or buy.

Now Negotiate Your Deal

Following our tips before you go shopping means you'll have the key information you'll need, no matter how prepared the dealership is. Then all that's left is for you to do the deal itself. You can make the whole process as easy as possible if you go to your dealership prepared with information from this article and from Edmunds' reviews of EVs and plug-in hybrids. 8 Steps to Buying a New Car quickly summarizes the best, most stress-free, cost-conscious way to buy any car. Including one with a plug.