Electric Vehicle Charging Stations

There are several types of electric vehicles (EVs) currently on the market. Plug-in hybrids, such as the Toyota Prius, Ford Fusion, Mitsubishi Outlander PHEV, and the Chevy Volt, are powered through a combination of gasoline and electricity (PHEVs). When the battery runs out, an on-board ancillary gasoline engine kicks in, extending the vehicle range. The Nissan Leaf and Tesla Roadster, on the other hand, are all-electric powered and run exclusively on on-board batteries with no ancillary gasoline engine.

The biggest problems getting EVs into the mainstream have always been battery capacity, lack of charging stations, and pricing. Vehicle manufacturers are making progress by improving battery issues, and many municipalities are helping to resolve the charging system dilemma. As availability of charging stations increases, demand will grow, prices will drop, and EVs will become more prolific.

Vehicle charging systems are often classified by charge level designation as; Level-1, Level-2, and Level-2 DC. The difference is in how the charge is applied, and in how long it takes to restore the battery of a depleted vehicle to full charge.

A Level-1 system can take up to 24 hours to fully recharge a depleted battery. These chargers typically plug into a standard, readily available 120V outlet and are often designed to be portable. They are the least expensive and useful for quick boosts when on the road, or as a home unit for low-use vehicles.

Level-2 systems usually require a special 240V AC source. Typically, they can restore a depleted EV battery to a full charge in eight hours or less, making this an ideal unit for overnight residential charging of a vehicle used for daily commuting.

Finally, there are Level-2 DC (formerly called Level-3) systems. These units convert the standard AC power to DC and feed it directly to the car’s battery bypassing the vehicle’s internal charger. The advantage is that a vehicle charge can be restored very quickly, often in less than a few hours. However, such systems are costly, shorten battery life if used often, and require special installation.

One system-wide limitation says Eaton Corp., a manufacturer of EV charging systems and other products is that, “All EVs sold today come with an onboard charger which is often the weakest link in the system. Such onboard units have a limited charge rate, thus excepting Level 2 DC chargers, they restrict what an external charging system can deliver.”

Before a long trip with an EV, it is wise to select a route that includes known charging stations and verify that they can accept the coupling mechanism for the vehicle. The Department of Energy maintains a website with an up-to-date list of all known charging stations. Additionally, there are smartphone apps that can pinpoint the location of charging stations and make EV travel easier.