Lotus has unveiled its 2015 challenger, the Mercedes-powered E23 Hybrid.
Lotus finished a lowly eighth in last year's Constructors' Championship but is hopeful that its new car will aid its recovery.
"The E23 Hybrid represents a massive step forward for us," said technical director Nick Chester.
"It’s no secret that we struggled with last year’s car so we’ve targeted every area that caused us an issue. We’ve made strong progress in the wind tunnel as well as in areas such as packaging and cooling.
"We expect the E23 to perform far, far better than its predecessor. In terms of what’s new, obviously a massive change for us is a new Power Unit supplier. We made this change as it looked and looks to be the one area of the car which could bring us the greatest performance gain. It’s not just performance, but reliability and driveability as well as packaging and cooling too."
The car will be raced by Romain Grosjean and Pastor Maldonado.
