The Toyota Prius Plug-in Hybrid Gasoline Electric
Toyota has introduced the production Prius Plug-in Hybrid electric vehicle (PHEV). All Prius cars up to this point have been standard gasoline electric cars (“hybrids”). This new Prius marks the first plug-in hybrid electric.
The “plug-in” moniker means that the vehicle is capable of going a few miles on electric power alone. Until now, this has only been available on some European and Japanese models of the Prius hybrid. This new rendition, however, is a step up from those with a larger battery pack (for longer range in battery electric mode) and the ability to select whether you’d like electric or standard hybrid drive at any time.
This will boost the car’s miles per gallon equivalent (MPGe) to 87, versus a current 49mpg in current combined mileage on the standard hybrid gasoline electric Prius.
Changes from the pre-production test fleet of 125 cars that were given trial through North America during the year are:
- Completely new battery design. Toyota’s goal was to reduce the cost, weight and volume of the pack from the NiMH system used earlier. The Li-ion pack is almost half the weight of the earlier pack, and so much more compact that the dimensions of the plug-in Prius are the same as those of the iconic liftback—i.e., there is no cargo penalty for plug-in capability.
Although the gross energy capacity of the pack is reduced (4.4 kWh), the EV range is increased. At a media preview of the introduction Toyota declined to be more specific as to the enabling mechanisms, citing some final issues that needed to be worked through by the battery supplier.
- EV mode is now user-selectable. The demo units defaulted to EV mode.
- Maximum EV speed is up to 62 mph.
- Maximum electric range is 15 miles
- A charge timer allows you to set charge start and finish time. (According to Toyota, one of the things they discovered during the demo program was that the battery packs responded better if they were allowed to rest prior to recharging.)
- The charge port is moved from the front driver-side fender to the rear passenger-side fender, while the charger is now moved back with the smaller battery pack. The result is a shorter distance from the charge port to the charger/battery, reducing weight.
- The charging cable is redesigned to be more flexible and lighter.
- Entune with plug-in hybrid applications.
Also, to keep in line with the 2012 Prius line of cars, some cosmetic changes have also been implemented to keep styling consistent.
The Prius Plug-in offers a user-selectable EV mode and two hybrid modes: Eco and Power. In EV mode, the hybrid ECU operates the vehicle using only MG2 if required conditions—such as sufficient battery state of charge and vehicle speed within ECV mode range—are satisfied.
Eco mode maximizes fuel savings across all driving conditions. It modifies or smoothes out the electronic throttle control program to reduce throttle response (throttle opening reduced to a maximum of 11.6%) and modifies air conditioning operation. As an ancillary benefit, it improves performance in low-traction conditions such as ice and snow because the reduced output helps to minimize wheel slippage. EPA label calculations do not include Eco mode.
Power mode increases throttle response in the middle range more than normal.
This is a definite step forward for the gasoline electric cars that Toyota has been producing to-date. Plug-in hybrids offer the best of both worlds: electric operation for clean, silent driving and the range options of a gas engine.