Hybrid hydraulic drive is half the weight

Permo-Drive, the Australian company that has developed a fuel-saving hybrid hydraulic drive system, has produced a new version which is almost half the weight and considerably smaller than first-generation prototypes. The company calims that its technology can reduce vehicle fuel consumption by 30% or more.

Permo-Drive`s "regenerative drive system" (RDS) captures energy normally wasted during braking and stores it hydraulically, releasing it back into the vehicle`s driveline when additional power is needed. It is similar to the technology developed by the Isle of Man company, Ifield.

The new version weighs around 150kg, 136kg less than the first generation RDS. When fully charged, it can generate power equivalent to a 254kW (340hp) engine with 1,350Nm of torque. A prototype will be ready for testing towards the end of this year, and commercial production is planned to begin in 2005.

Recent tests on a US Army vehicle equipped with the original RDS showed a 27% improvement in fuel economy, a 36% boost to rapid acceleration, and a 60% improvement in deceleration, compared to engine braking. Tests in Australia are said to have yielded fuel economy gains of 33% or more.

During braking, energy is captured by a flow of oil from a low-pressure tank to a high-pressure accumulator. During acceleration, a processor controls the release of oil to enhance fuel economy and reduce emissions.