Williams will not use KERS at Albert Park.

The Williams F1 team will not use a potentially race winning new technology at the Australian Grand Prix on March 29.

It has decided against starting the 2009 season with the promising, but unproven, Kinetic Energy Recovery System which is now allowed under the latest Formula One regulations.

It can give a potential benefit of up to 80 horsepower in short bursts but the KERS systems are heavy and, so far, not proven.

Williams is not the only team with doubts about KERS as even BMW- Sauber, which has one of the most advanced of the new systems, has yet to decide if it will use its KERS at Albert Park.

McLaren-Mercedes is almost certain to use the new system, which would likely force Ferrari to also fire up with the new system to ensure a level-pegging start to the '09 championship battle.

"The situation here is that we are working to bring the technology to the car but we are not going to race it in Melbourne," a Williams spokesman said yesterday.

"We will introduce KERS as and when we have a system that can improve performance."

BMW-Sauber has done a lot of work on its system this week in Bahrain but one of its drivers, Nick Heidfeld, told the Herald Sun yesterday that it was not confirmed for the AGP.

I'm very interested myself to find out how many teams use it. We have not decided," Heidfeld said.

"So far Mercedes is the only team to say they use it."

Heidfeld said KERS could provide a winning edge at some tracks but would be a potential handicap, because of its weight, at others.

"Some circuits it suits more than others. Here in Bahrain it seems to suit the circuit.

"Melbourne will be a circuit in the middle. It's not ideal but it's not as bad as, say, Monaco."

Heidfeld also said it is relatively easy to adapt to driving with KERS, which gives a turbocharger-style surge of extra power for up to six seconds. It is triggered by a button on the steering wheel.

"It's not hard to get used to, but its very interesting, like normally with new things coming up," he said.

"There are a lot of things to learn and explore. It's good fun to find out how it is. We are still developing and it's not perfect, but we are hoping it will be perfect and give us an advantage over a non-KERS car."

BMW-Sauber uses an electrical KERS system for its energy storage while Williams is using a compact flywheel which spins at very high speeds.

Other teams are believed to be using some form of hydraulic system.

There have been problems, with a BMW mechanic being electrocuted during early trials last year. He was taken to hospital but not badly injured.

The KERS package is part of a raft of rule changes for the 2009 season which includes new wings, slick racing tyres and fewer aerodynamic body parts. The objective is to allow closer racing and more passing.

Williams said it believes there is more chance of improving its results this year with improvements outside KERS, which is why it has delayed its introduction beyond the AGP.

"The rationale for this is that the greatest performance opportunities are currently in the weight distribution, balance and optimising set- up for the slick tyre. This is where we focus initially," the Williams spokesman said.

"As we are developing our own motor and our own energy storage system, it will take longer and be higher risk, but our approach offers a higher potential reward.

"It also means that the work we are doing for our Formula One programme is accelerating the introduction of this technology for other applications.

"In the medium term, this may prove to be the biggest contribution of KERS as the FIA and Williams hoped from the outset of the initiative.

Naturally, the date for the introduction of our system to the car will be kept under review."

What is KERS?

A Kinetic Energy Recovery System is designed to harness the energy normally lost as heat when a Formula One car brakes from high speed.

Similar systems are already in use in some hybrid road cars, including the Toyota Prius and Honda Civic, to re-charge their on-board electric batteries.

In F1 cars, the energy is recovered and stored, to be released in short bursts as extra horsepower for acceleration.

KERS is part of a package of technical changes for the 2009 season to improve racing and boost the amount of overtaking.

There are a variety of KERS systems in the grand prix world and, although teams are very secretive about their design and operation, they use either electrical, flywheel or hydraulic systems to store the energy. It is released when the driver hits a button on the steering wheel.

KERS delivers an estimated extra 80 horsepower for up to six seconds, but the penalty is extra weight which could add as much as 50 kilograms to a car.