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What is a Plug-in Hybrid, and how do I get one?

Definition anchor

A PHEV (Plug-in Hybrid Electric Vehicle) has the following characteristics:

  • It is propelled by both a gasoline engine and an electric motor
  • Has batteries that can store enough electric energy to go at least a few miles
  • Has a charger for those batteries that can be plugged into an outlet
HEVs anchor

All HEVs (Hybrid Electric Vehicles) presently produced are ultimately just gasoline cars. They do reduce emissions, and they may improve fuel efficiency (compared to an equivalent, non-hybrid car). However, they are fueled exclusively by gasoline.

PHEVs anchor

A Plug-in Hybrid car, in contrast, can also be fueled by electricity from an electrical outlet. Initially, a PHEV uses less gas than an HEV, because it can draw energy longer, from its larger battery. For example, a Toyota Prius' 50 mpg efficiency can be improved to about 100 mpg when operated as a PHEV. Eventually, when that storage of electrical energy is depleted, a PHEV is no more efficient than an HEV.

EV distance anchor

HEVs and PHEVs are rated by how far they can go just on electricity stored in their batteries. For example, a stock Toyota Prius is an HEV-2, meaning that its battery holds enough energy for about 2 miles. A Hybrids Plus Prius conversion is a PHEV-30, meaning that its battery holds enough energy for about 30 miles. Note that a Prius PHEV must still use some gasoline because, by design, its gas engine must operate when going 35 mph or more.

Conversions anchor

Presently, the best way to get a PHEV is to convert a production HEV. This entails:

  • adding a charger and a power cord
  • increasing the electrical storage capacity of the batteries
Prius anchor

Most PHEV conversions are done on the Toyota Prius because:

  • it can operate purely on electricity (unlike, for example, the Honda Insight)
  • it is efficient, well designed and popular
Resources anchor

This table lists all the options for Prius PHEV conversion.

See also:

  • CalCars is a California organization actively involved in PHEV conversions
  • is a wiki repository of all things PHEV
  • eaa-phev is a Yahoo group for people interested in PHEVs
  • promotes PHEVs

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