Is Renault Formula One's most under-appreciated brand?

The story of Formula One’s power unit war has been more or less consistent since the hybrid formula debuted in 2014 – Mercedes first, everyone else second.

Honda occupies a special ‘other’ category in this race – its troubled power unit has never really presented a threat to any other. However, as Fernando Alonso continues to tell the media and presumably wakes up screaming to himself every night, if you’re not a Mercedes driver, you’re only a bit player in any case.

If you’re not first, you’re last, if you will.

But Formula One power units are incredible bits of technology, and the very fact that some of the most significant car manufacturers in the world can’t master the mandated hybrid V6 turbocharged formula is testament to their complexity

Thermal efficiency, after languishing for so long in the general automotive world at between 25 and 30 per cent – that is, as much as three-quarters of the fuel’s energy is wasted as heat – is now at around 50 per cent in a Formula One engine, and there’s no sign that even the class-leading and catchily-titled Mercedes PU106C has hit the development ceiling.

While the Silver Arrows has forged ahead undaunted Ferrari has also impressed by turning its underwhelming 2014 offering into the race-winning 2015 power unit and potential-laden 2016 package.

But Renault has long been the dark horse of the power war. It’s V8 engines pre-2014 were well optimised, but its first hybrid turbo offering was only so-so. Pre-season testing showed it to be worryingly unreliable, but fixes ahead of the season-opening Australian Grand Prix had Daniel Ricciardo temporarily on the podium before his car was disqualified for breaking fuel flow rules.

No matter, because tweaks throughout the season ensured Red Bull Racing was in the best position to capitalise on any misfortune to befall the runaway Mercedes team, and indeed it did so in Canada, Hungary, and Belgium that season.

But in 2015 it took a dramatic step backwards, and the strained relationship between the once-great Red Bull Racing-Renault partnership was pushed beyond its tolerance.

Red Bull Racing, eager to mark 2014 down as a blip after four year-strong run of double championships, demanded Renault work double-time to close the gap to Mercedes, and it did the same. The result was a Renault power unit that wasn’t properly tested bolted into a chassis that was poorly balanced.

Pushed by Red Bull management’s public slating of the company – who could forget Red Bull supremo Dietrich Mateschitz’s claim that Renault “destroyed our enjoyment and motivation” of Formula One? – both parties agreed to terminate their contract for 2016. The former was to decide on whether it would withdraw from the sport, the latter was to negotiate with Mercedes for an engine.

Renault decided to buy Lotus and redouble its efforts, but Red Bull was denied by every other power unit manufacturer. This left it on the brink of a forced withdrawal from the sport until a deal could be brokered with Renault – provided that the Austrian team be prevented from further public outbursts against the French company.

Red Bull Racing’s solution was to badge its power units TAG Heuer, eliminating the need to acknowledge its continuing partnership with Renault after the ugliness of the previous year and leaving Renault to worry about the PR of only its own struggling team.

At no stage did either party expect the 2016 currently taking shape. Not only was Renault’s off-season power unit development more fruitful than anticipated, it’s B-spec upgrade tested in Barcelona and due for debut in Monaco purportedly carries with it a 0.5-second gain in lap time – roughly the current gap to Mercedes.

If Renault’s predictions turn out to be true – and judging by Daniel Ricciardo, Kevin Magnussen, and Esteban Ocon’s reviews of the power unit after last week’s in-season test there’s every chance they will – how will that go down with Red Bull Racing, which may suddenly find itself in regular contention for wins?

“I have to pay compliment to our TAG Heuer engine partners who have done a great job in making progress,” said RBR team principal Christian Horner ahead of this weekend’s race.

That’d be about right.

For three of Red Bull Racing’s four championship-winning seasons Renault took a back seat to team title sponsor Infiniti, reaping little recognition for its efforts – indeed Red Bull often celebrated victories *despite* what it claimed was an underpowered engine.

In 2014 and 2015 Renault received only hate from its partner to such a degree that it considered leaving Formula One.

Now in 2016, when it looks to finally bounce back and return to the top step, TAG Heuer will take Renault’s spotlight.

After powering Red Bull Racing to 51 victories, the men and women at Viry-Châtillon could be forgiven for feeling their relentless toil has been under-appreciated.

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