The conclusion of the 2014 season marked the end of a challenging but ultimately productive year for Renault Sport F1. Sweeping changes to engine regulations ahead of the season presented the team at Viry-Chatillon with a fresh and unique set of challenges.

"We've had a baptism of fire this year," says Renault Sport F1 Managing Director Cyril Abiteboul. "F1 set itself incredibly high standards with the new engine regulations. We endured a difficult testing period and first few races, but it's a testament to the sport, and the people who dedicate their lives to it, that all its engine manufacturers managed to deliver technologies compliant with the regulations and standards required by Formula One. No one would have expected such a level of competitiveness after pre-season testing.

"As far as we are concerned, everyone at Viry and our partners - technical and teams - put a huge amount of effort into taking such important strides over a short period of time. We reassessed our goals and made a series of tweaks to gradually regain the reliability and performance we expect of ourselves. Three wins and so many points are the result of our non-stop hard work."

Since the opening race in Melbourne significant gains have been made in energy recovery and Power Unit efficiency, allowing drivers maximum power output for longer periods. In fact Renault teams were approximately 5% more efficient in Abu Dhabi than they were at the start of the season, a significant improvement in a sport more used to the concept of marginal gains. This equates to a time gain of some half a second.

Speeds and performance were also enhanced. For example, at the Italian Grand Prix, lap times were consistent with those of 2013 despite using a third less fuel per lap. And while overtaking another car during the race, Daniel Ricciardo reached 362.1kph, smashing the previous year's top speed by an impressive 20kph. Sao Paulo's qualifying session also witnessed some of the fastest lap times ever recorded there as a result of the Power Unit's architecture being particularly well adapted to the circuit's characteristics.

Huge improvements were similarly made in reliability. After a shaky start, the Renault Energy F1-2014 Power Unit covered more than 90,000 on-track kilometres over the course of the season between the four Renault Sport F1 teams. This equates to an average of 11,250km per driver - or more than 37 race distances. In fact, Daniil Kvyat sits third in the list of total distance covered by an individual driver since the start of the 2014 season, while one single Power Unit has covered more than 4,300km.

"Highlighting one single element as the source of our improvement would be impossible," Abiteboul explains. "Instead, it's the development of multiple parts that has resulted in a much-improved PU to the one that began pre-season testing last January.

"Components have been modified to make them more robust; chassis teams have learnt a great deal about integration and cooling; engine and energy management control advances have enhanced driveability and efficiency; and the ‘knocking' sensation caused by cylinder pressure has been neutralised thanks to the help of our official fuel partner, Total. Together, these elements have undoubtedly impacted on results."

That more robust and competitive package soon saw Renault-powered Red Bull emerge as the greatest threat to Mercedes, whom it was able to ambush on a number of occasions! Indeed, three wins for Daniel Ricciardo - the only driver other than Lewis Hamilton and Nico Rosberg to win in 2014 - and five further podium results helped the team claim a comfortable second place in the constructors' championship, while the Australian also finished third in the drivers' title race.

"It's true that second in the constructors' championship is not our usual target, but the result demonstrates that we never stopped pushing hard and constantly improved. Obviously we have a huge job list ahead of next season, but also a clear direction and focus, as well as the determination to challenge for more wins in 2015.

"Mercedes has set the bar extremely high, most notably in terms of how their Power Unit and chassis teams have seamlessly worked together. We would like to congratulate them on a job well done, no doubt the result of years of determination and hard work at Brackley and Brixworth. We also wish to extend our thanks to our partner Total. Their relentless efforts in developing fuels and lubricants contributed to our overall performance this season.

"We are extremely motivated by the prospect of another season of competition, just as we are determined that the Energy F1 should join the illustrious list of title-winning Renault engines."