Lexus GS RX400h Hybrid Drive
The RX 400h’s Hybrid Synergy Drive system combines a 3.3-litre V6 petrol engine with a 165bhp front electric motor that has a world’s-best power to weight and volume ratio, a high voltage battery and a generator. A second electric motor at the rear axle gives the vehicle an electric four-wheel drive capability – E-Four – that is automatically engaged when required.
In any journey, the system will operate in different modes in order to maintain the maximum efficiency, with power from the engine, the electric motors or a combination of both. Whenever the vehicle comes to a halt, the engine will automatically be switched off to minimise fuel consumption.
The RX 400h can run on its electric motors alone at start-up and low to mid-range speeds, which cuts exhaust emissions to zero. In normal driving conditions, a power split device will divide output from the engine between driving the wheels and powering the generator, which in turn charges the high-voltage battery. This means the vehicle never has to be off the road to be charged.
Further energy is gained during braking or declaration with the electric motors operating as high output generators to recover kinetic energy that would usually be lost as heat and storing it as electricity in the high-voltage battery.