There are two types of cars that get powered up from the electric grid: The Plug-in Hybrid (PHEV) and the Plug-in Electric or Battery Electric Vehicles (BEV). What's the big deal with plug-ins you ask?  Well, they're bringing us one step closer to getting off gasoline (and middle-eastern oil) once and for all, and in some cases they already have!

Plug-in Hybrid (PHEV)

A Plug-in Hybrid works just like a regular Hybrid, except that it can be "plugged in" to further charge the batteries.  In normal hybrids, like the Toyota Prius, the batteries are just charged through regenerative braking, but in a plug-in the batteries also are charged through an electrical outlet.  This means that more batteries are on-board to store more of this electrical power coming from the grid.

The more batteries you have, the farther you can go on electric power without having to rely on gasoline.  When the juice in the batteries is all used up, the gas engine is relied on and the batteries get some power by regenerative braking.  The advantage of a PHEV is that more batteries are added so the car relies less on the fossil fuel engine than do regular Hybrids.

Advantages over a Battery Electric Vehicle:

• Farther range due to on-board gasoline engine (hybrid)
• Current Hybrids can be retrofitted to operate as plug-in hybrids (see this page from EAA on Prius hybrid plug-in conversion kits)

Battery Electric Vehicles (BEV)

A BEV doesn't have a gas engine on-board and is totally reliant on the batteries.  Since BEV's don't have a gasoline engine, it means they have more room for batteries, so their battery-only range is much higher than a PHEV.

Advantages over PHEV:

• No oil money to regimes that want to see the downfall of America

All Plug-Ins

A plug-in doesn't necessarily mean you are becoming less reliant on fossil fuel.  If your power grid is heavily reliant on fossil fuel generation (coal/natural gas/oil) you are still powering part of your car with fossil fuel.

Advantages of all cars that get some portion of their power from the electric grid:

• As the power grid cleans up, so does your car's power source
• less oil from countries that wish America didn't exist!
• the potential exists for you to install solar/wind at your home and power your car with that!

The biggest challenges designing cars that use batteries are the cost/weight/power density of the batteries.  Luckily battery technology is increasing rapidly.  One company that makes batteries for cars, A123 systems recently had an IPO.

Further hurdles facing plug-in vehicles are remote battery charging stations so plug-in owners can charge up away from home (something EV battery charging station builder and service provider Better Place is working on) and regulatory hurdles involved in letting consumers of electric vehicles  install vehicle charging stations in their garages.  Consumers testing out the BMW Mini-E experienced this first-hand in the Mini-E electric vehicle trials in New Jersey. Plug-ins charge much faster when they are connected to 240 V service , which requires certification to install.  Since states will have their own rules on certifying these charging stations, regulations will need to be simplified.

Thankfully there are some organizations working on making electric cars an American mainstay.  The Electrification Coalition (whose members make up a "who's who" of clean energy technology leaders) states on their website:

As its first official act, the Coalition today released the Electrification Roadmap¸ a sweeping report detailing the dangers of oil dependence, explaining the benefits of electrification, describing the challenges facing electric cars, and providing specific policy proposals to overcome those challenges.

Plug-in America is a great resource for information regarding Electric Vehicles, but they only seem to be focused on totally EV, not PHEV. I utilized one of their lists to help refine my list of available plug-in electric cars for 2010.  And what Plug-in America is doing for BEV, the California Cars Initiative is doing for PHEV. And the Electric Auto Association has a ton of useful information regarding cars that get power from batteries.

Whether it is a PHEV or a BEV, plug-ins make us less reliant on oil from the middle east, and this can only be a good thing.  Learn more about plug-ins, encourage their development, and look forward to buying one in the next few years!