The French manufacturer - 2015 suppliers to Red Bull and Toro Rosso - suffered their first winless season since 2007 this year, while their total of three podiums was their second-lowest return in over a decade. Lead team Red Bull, meanwhile, finished fourth - the joint-lowest for a Renault-powered squad since 2001.
"Fourth in the championship for Red Bull is no doubt hard to accept and we all share that responsibility," said Renault Sport F1's managing director Cyril Abiteboul.
"At Toro Rosso, the championship position may not be as hoped, but with more than double the points of 2014, it's been a strong year overall for them and we are proud to have worked together to achieve this.
"We have not reached the targets we set for ourselves, but I hope this year will be seen as an aberration to our usual good form.
"At the end of a very challenging season, both on and off track, I would like to thank everyone at Viry-Chatillon for their hard work. At the start of the year when we came under fire it would have been easy to lose motivation, but all have kept their heads down and kept development on track."
Remi Taffin, director of operations at Renault, admitted the 2015 season finale in Abu Dhabi had provided little comfort, with Red Bull's Daniel Ricciardo and Daniil Kvyat their only two points scorers in sixth and 10th respectively.
"We can take some solace from having four cars see the finish, but it is nevertheless a disappointing way to end a tough season," Taffin said. "The final results do not do justice to a phenomenal effort behind the scenes to recover performance and to the spirit we have within the team."
Renault are still in talks to formally take over Lotus and seal a return as a works team, with Abiteboul saying on Friday at Yas Marina that an announcement regarding Renault's future would "very likely" be made this week.