If you are designing an all electric car, in-wheel electric motors could replace any on-chassis motors, and having four of them independently coordinating whether they function as generator or motor allows sophisticated power management – improving efficiencies. In-wheel motors also allow more payload space on the main chassis.
According to Mitsubishi’s 2005 Annual Report, page two, in May 2005 they announced in-wheel motor technology ready to deploy. In-wheel motors eliminate the need for a transmission or power train and overall they are far less expensive to maintain. They represent a huge leap forward in automotive technology.
Another significant innovation coming soon, also less expensive to maintain, is the Serial Hybrid Car, where a diesel engine turns a generator to charge a battery-pack and power an all-electric drivetrain. These cars were waiting for two things – ultra-clean 40% efficiency diesel engines, and batteries with an energy density of 200 watt-hours per kilogram. That day is here.
A serial hybrid car can run on two things – battery power or power from an on-board diesel generator. Using battery power, a mid-sized car – loading up on electricity at $10 per kilowatt-hour from the grid – can be driven for under four cents per mile. Using diesel fuel at $3.00 per gallon, the same serial hybrid car can transfer electricity directly from the generator to the motor and be driven for ten cents per mile – about thirty miles per gallon.
The range of a serial hybrid car depends on the size of the diesel engine, the capacity of the fuel tank, and the quantity of batteries, to name a few key factors, but 300+ miles is more than feasible. The tradeoffs between range, weight, and price are infinite. Will a major automaker announce a serial hybrid car tomorrow at the Detroit International Auto Show 2007? And if so, will it be the real deal? Because the serial hybrid car is waiting to be built – inexpensively – and sold by the millions around the world.
Later, with in-wheel motors and on-board reforming capacity, if advantageous, fuel cell systems could replace the diesel/battery systems on the same chassis and drivetrain. It takes time to green a newly industrialized planet, but evolution and creation are wonderful things.