In 2010 Red Bull won its first of four consecutive world championships – both driver's and constructor's – with Sebastian Vettel behind the wheel and Renault providing the engines. After the series switched from V8 engines to new turbocharged V6s, however, the new Renault engine package fell off the pace, leaving Mercedes to dominate in its stead. The close relationship between Red Bull and Renault has steadily soured over the past couple of years, to the point that the team was preparing to dissolve the partnership early – even though it had no new engine deal to replace it with. And it's had a hard time finding one. Discussions with Mercedes, Ferrari, and Honda – the other three engine suppliers on the grid – have born no fruit, and the prospect of a fifth, independent engine supplier joining the series won't be ready in time for next season.
The question, then, is what engines Red Bull will be running next season. And the answer, at this point, is that we don't know. But the signs are pointing toward another season under Renault power. However they may not be branded as such. As Renault prepares to re-acquire the Lotus team that was once its own and rebrand it in its own image again, the French automaker may not be keen to divide its image. As a result, we could see Red Bull running the same Renault power unit, but badged either as its own (the name "Energy" has been touted) or as an Infiniti engine, referencing Renault's sister brand which has long been the team's title sponsor.
It wouldn't be the first time we would see F1 engines rebadged under another name – even Renault engines specifically. 1998 saw Williams run Renault engines rebadged as Mecachrome, and Benetton run the same package labeled as Playlife. Sauber, for another example, also ran Ferrari engines rebranded under its title sponsor Petronas. Another proposal which Red Bull ultimately rejected could have seen the team running separately developed Ferrari engines but with Alfa Romeo branding.
We may yet see Alfa resurface in some capacity – especially with Sergio Marchionne's backing and Ferrari spinning off into a corporate entity entirely separate from Fiat Chrysler Automobiles. As for Red Bull, its signing on for next year's entry list is far from a guarantee that it will indeed return. But it's a step in the right direction. We'll just have to hold on to see how it materializes in the end, and under whose motivation.