Renault have become the first team to say they will definitely use their new energy storage and power boost system (Kers) at the year's first race.
The technology stores energy that would have been wasted while braking and allows drivers a boost of an extra 80bhp for seven seconds each lap.
BMW were the first to say theirs was ready - but did not say whether they would use it in Australia on 29 March.
The systems, similar to those in hybrid road cars, are optional in 2009.
The systems will give teams that use them an advantage when it comes to overtaking due to the extra power available.
But because of the weight of the Kers and the difficulty of packaging it brings compromises.
McLaren and Ferrari have also not said whether they will use Kers in Australia.
Williams, Toyota, Red Bull, Toro Rosso, Force India and Brawn GP will definitely not use it.
Brawn, recent pace-setters in pre-season testing, would have to fundamentally redesign their car to fit a Kers system - which they are unlikely to do.
BMW team boss Mario Theissen said their Kers was "race-ready" but added: "Now it is just a matter of weighing the pros and cons."
BMW will decide whether to fit Kers to their cars in Melbourne, Australia, where practice starts on 27 March, after evaluating a complex set of parameters determining whether it will give them an overall performance advantage.
"On the positive side, the drivers would have an extra 82 horsepower at their disposal for 6.6 seconds per lap," said Theissen.
"However, the system adds weight to the car and this has an impact on the car's weight distribution and tyre wear.
"We will make a decision on a driver-by-driver, circuit-by-circuit basis."
Kers could also be a bigger disadvantage for taller, heavier drivers such as BMW's Robert Kubica in comparison to their smaller, lighter rivals, such as the Pole's team-mate Nick Heidfeld.
Theissen stated: "The minimum weight of 605kg stipulated for the cars in the regulations includes the driver.
"The difference between the actual weight and minimum weight is levelled out by positioning ballast around the car to optimum effect.
"Traditionally, this means that a heavier driver has been at a disadvantage as he has had less ballast to balance out the car. Using the Kers will further reduce - by the weight of the system - the amount of ballast available.
"In order to prevent F1 from becoming a jockeys' competition, we are pushing for an increase of the minimum weight in the future."
Kers is not mandatory this season but it has been introduced as an option to try to introduce sustainability to F1 and in an attempt to accelerate the development of such systems in road cars.
BMW is one of the road-car manufacturers that already employs such systems in its range and they have been F1's most enthusiastic advocates of the system.
BMW vetoed attempts by other teams to delay the introduction of Kers by at least a year because of the cost of developing it in a global recession.
Theissen told BBC Sport that the first fruits of BMW's work on Kers in F1 would be seen in its road cars as early as next year.
He said developing Kers for F1 had been a "huge challenge".
He added: "When I look back at how far we have come in such a short space of time, it really is very impressive. Here, Formula 1 has taken on the role of technology accelerator for series production cars of the future."
The F1 team of Toyota, which is the market leader in so-called "hybrid" road cars using similar systems, have already stated that they will not be using Kers at the start of the season.
The new Brawn team, which has set the pace in pre-season testing since confirming its survival less than two weeks ago, has no plans to use Kers in 2009.
Source:
http://news.bbc.co.uk