Track testing of the Spark-Renault racing car began this month and has generated fierce debate over its technical credentials. To Chris Vagg, former Brawn and Mercedes AMG F1 engineer, a little caution is not necessarily a bad thing.
“Formula E promoters issued technical regulations for constructors a little earlier in the year. While there is now only one permitted vehicle for the 2014 season – the Spark-Renault – it seems to have stuck to the specifications I saw. And yes, the regulations do seem to be fairly conservative in terms of what is allowed.
For example, according to the regulations, up to two motors are permitted, but they must be placed at the rear of the vehicle and connected to the rear wheels. (The recent Current E graphic appears to show only one motor, though of course there may be some trickery in the packaging.) That rules out any possibility of the front wheels being connected to the powertrain, which vastly reduces the opportunity to capture kinetic energy that is otherwise wasted under braking. And as the front wheels generally do 70% of the work when braking, the Spark-Renault can only recover – at best – 30% of this lost energy.
It seems peculiar decision to make, considering that the cars will face such debilitating range problems in the first year that every driver is expected to use two cars just to make it to the finish line.
However, even if capturing energy from the front wheels were to be allowed in future seasons, actually doing so is easier said than done. There are two obvious ways to go about it, both of which involve major drawbacks:
- Adding a motor in the nose, connected to the front wheels. Fitting a unit into the skinny nose would be particularly difficult, and adding weight in the raised nose cone would immediately create handling problems. There would also be safety concerns – the nose would no longer crumple but rather act as a battering ram in the event of a collision.
- Mounting motors in the wheels, as hub motors. This is still viewed as ‘next generation’ technology however, in that wheel-mounted motors are a more complex solution than conventional chassis-mounted motors and aren’t nearly as widespread. Engineers are also very wary of adding unsprung mass – that is, mass that is not contained within the chassis and therefore not supported by the suspension. There would also be safety concerns in adding mass to the wheels, which can become detached in crashes and in the pit lane – loose, heavier wheels could be rather dangerous.
Does it matter that the cars are not nearly as avant-garde as they could be? Given that all vehicles racing in the first season will be identical, probably not: getting all the cars around the track a second per lap faster wouldn’t gain anyone a competitive advantage.
Setting a somewhat conventional benchmark may also make the sport more accessible and attractive to teams and manufacturers by using existing technology they are familiar with and understand. It’s making sure you walk before you can run.
If the technical parameters were completely unrestricted, the sport would quickly turn into a free for all. Too many options would open up the very real possibility arriving at the grid with a racing car far slower than those of competitors despite huge investment. Just look at F1.
The alternative is to start with conventional tech to prevent too much ridiculous investment, and in time, relax the regulations to encourage greater innovation. That seems to be the approach that Formula E has adopted.
Attracting teams has been a big leap forward for the new series. Racing cars that can be easily made faster will lure eager manufacturers into the second series. The benchmark may be conventional and it may have been set low, but it gives the new sport all the space it needs to develop fast and furiously in the future.”