The Lotus E20 (originally known as the Renault R32) is a Formula One racing car designed and produced by the Enstone-based Lotus F1 Team for the 2012 Formula One season. The chassis was designed by James Allison, Naoki Tokunaga, Martin Tolliday, Nick Chester and Dirk de Beer with Renault continuing to supply engines. The E20 was the twentieth Formula One car to be designed at Enstone since 1992, and was named in tribute to the contribution made by the facility and its personnel in their twenty-year history. The car was also the first from Enstone to carry the Lotus name, since the team ceased using the Renault name following their renaming from Lotus Renault GP at the end of 2011. The car, which was launched by the team on its website on 5 February 2012, was driven by 2007 World Drivers' Champion Kimi Räikkönen and reigning GP2 Series champion Romain Grosjean, both of whom returned to Formula One after a two-year absence.

The car made its competitive debut at the 2012 Australian Grand Prix, and in the twenty races of the 2012 season, recorded a race win in Abu Dhabi and nine podium finishes to finish fourth overall in the World Constructors' Championship.

Design

Ride height system The Lotus E20 was planned to feature a "reactive ride height" suspension system — a mechanical device designed to maintain ride height under braking — at the start of the 2012 season. Lotus (and formerly both their immediate predecessors, Lotus Renault GP and Renault F1 Team) had been developing the system since January 2010. The system used hydraulic cylinders located in the brake calipers and suspension push-rods to make minute adjustments to the ride height of the car, thereby keeping the ride height at an optimal level throughout the race and providing stability during braking. This initially had the approval of the FIA, who reversed their position one week later ruling that such systems were in breach of their regulations, on the grounds that the primary function of such a device was improve the aerodynamic performance of cars, and was therefore in violation of Article 3.15 of the technical regulations, which states that "any device that influences the car's aerodynamics must remain immobile in relation to the sprung part of the car". The teams were notified of the FIA's decision on 20 January 2012, and as a consequence, the reactive ride height system did not feature on 2012 cars.

Testing problems The team was forced to withdraw from the second pre-season test in Barcelona when Grosjean complained about a "strange" feeling in the chassis while driving on the opening morning of the test. The team gave no official diagnosis of the problem at the time, but speculation within the media suggested the problem was related to the front suspension and that the problem presented itself at the Circuit de Catalunya because of the higher lateral loads placed on the chassis at the circuit than those experienced at Jerez. James Allison, the team's technical director, later confirmed that the team had identified the problem as being the mounting of the upper front wishbone on the rear suspension arm. Grosjean had been testing the chassis designated E20-02 at the time; the chassis E20-01 was returned to the team's Enstone facility following completion of testing at Jerez. Upon discovering the problem, Lotus initially prepared chassis E20-01 to be transported to Barcelona to complete the test, but simulations revealed that the problem was also present on E20-01, and so the team decided to withdraw from the remainder of the test with immediate effect. The problem was then corrected in time for the team to start the season.

"The Device" The Lotus E20 was one of the only cars on the 2012 grid to use a version of the "double-DRS" system used by Mercedes on the rear wing of the W03 chassis. The wing used the F-duct concept developed by McLaren in 2010, which blew air across the surface of the wing to "stall" it, thereby cancelling out all downforce and drag running over the wing, allowing the car to achieve a higher top speed. The system developed by Mercedes was reported to create an F-duct effect over the front wing when the Drag Reduction System (DRS) flap in the rear wing opened. Opening the flap would expose two vents, which channeled air back through the car and over the front wing, cancelling out the downforce generated by the front wing with the intention of increasing stability in high-speed corners. Lotus initially opposed the system, and filed a formal protest as they believed it to be a moveable aerodynamic device and therefore in violation of Article 3.15 of the sport's technical regulations, the same Article under which the E20's reactive ride-height system had been challenged. The FIA ultimately rejected Lotus's protest, allowing Mercedes to continue using the double-DRS device and paving the way for Lotus to introduce their own version of it.

Two days after the 2012 Hungarian Grand Prix, the teams unanimously agreed to ban the use of double-DRS systems for the 2013 season. Nevertheless, Lotus continued their development of a double-DRS system, which they referred to as "The Device", and anticipated its introduction at the Belgian Grand Prix, one month later. However, heavy rain in the first two practice sessions at the Spa-Francorchamps circuit delayed The Device's introduction. The team's plans were further put on hold after Grosjean was banned from taking part in the Italian Grand Prix for his role in a multi-car pile-up at the start of the Belgian Grand Prix. Grosjean was replaced by the team's testing and reserve driver, Jérôme d'Ambrosio, but d'Ambrosio's inexperience with the 2012-specification of cars and the low-downforce nature of the Monza circuit — which meant that any gain a double-DRS system had to offer would be negated — prompted the team to delay The Device's introduction even further, naming the Japanese Grand Prix in early October as their planned point of introduction. The team used the double-DRS system as planned during Friday practice, but shelved it until the third round of Young Driver Tests in November after being unhappy with their progress. Räikkönen admitted that using the system made finding the proper setup for the car much more difficult than without it. By comparison, Red Bull Racing introduced their own variant on the system at the Singapore and Japanese Grands Prix, which was credited with aiding Sebastian Vettel in securing two race wins.

By the end of the season and in spite its extensive development programme, "The Device" was never raced. However, the concept was carried over to the Lotus E20's successor, the E21, with the team pledging to continue development throughout the 2013 season. The system was finally raced for the first time at the 2013 British Grand Prix, when it was fitted on Räikkönen's car; the team opted not to use it on the sister car of Grosjean so as to evaluate its performance relative to the older specification of car.

Coandă-effect exhaust With the double-DRS "Device" shelved for the foreseeable future, the team instead turned their attention to the exhaust, introducing a Coandă-effect system for the Korean Grand Prix. The system, also used by McLaren and Ferrari, used the curved shape of the bodywork at the rear of the car to guide the flow of exhaust gases, creating a low-pressure area over the car's diffuser. The team had previously considered launching the car with a Coandă-effect system, but opted to start the season with a conventional exhaust layout as they felt it was more important to start the season with a car that they knew was competitive rather than attempt to understand both the car and the complex properties of the Coandă effect at the same time.

Season review The Lotus E20 showed its potential early in the season when Grosjean qualified third for the Australian Grand Prix. However, the team would go on to experience a difficult season in which they never quite made the most of the car's potential, let down by poor race management and frequent entanglements in on-track incidents. Despite predictions that the team would be competing for race wins — if not the Drivers' and Constructors' Championships' — as early as April, the team would remain winless by October.

Grosjean's strong performance in qualifying for the race in Australia came to nothing when he made contact with Pastor Maldonado on the second lap and retired on the spot. Räikkönen, who had struggled in qualifying and started the race from seventeenth place, made the best of a bad situation to finish the race seventh. The team fared little better in the next race in Malaysia; both Grosjean and Räikkönen qualified comfortably inside the top ten, but Grosjean made contact with Michael Schumacher on the first lap and slipped down the order before spinning off, while Räikkönen was given a grid penalty for an unscheduled gearbox change and had to fight to recover to fifth. The team's troubles continued in China; once again, both drivers qualified inside the top ten, but Räikkönen's race was compromised by poor tyre management and he lost eleven positions in a single lap. Grosjean, on the other hand, managed a clean race and was rewarded with his first points in Formula One.

The Bahrain Grand Prix represented a breakthrough for the team, with both Räikkönen and Grosjean finishing the race on the podium behind race winner Sebastian Vettel. Both drivers had challenged Vettel for the lead over the course of the race, and while neither managed to catch the reigning World Champion, it was an encouraging sign for team, and one that they would back up at the next race in Spain, with Räikkönen scoring his second consecutive podium after attempting a daring strategy in which he tried to force race winner Pastor Maldonado and Fernando Alonso to drive beyond the life expectancy of their tyres. Räikkönen ran out of laps before Maldonado and Alonso ran out of grip, and the 2007 World Champion finished third, with Grosjean fourth.

The team's fortunes came crashing back down to earth in Monaco when Grosjean was at the centre of a first-lap accident that put himself, Maldonado, Kamui Kobayashi and Pedro de la Rosa out of the race. Räikkönen, meanwhile, struggled after losing valuable track time during Friday practice, as he was unhappy with parts introduced onto the car for the race. He qualified eighth and went on to finish the race ninth. The team's poor form in Monaco proved to be an exception, rather than the rule, as Grosjean went on to finish the Canadian Grand Prix in second place after race leaders Alonso and Vettel fell victim to the ultra-sensitive Pirelli tyres; Grosjean later admitted that he had not thought a podium was possible until he found himself running second with three laps left to run. Räikkönen, on the other hand, missed out on a spot in the top ten on the grid, and so had to work his way up from twelfth to eighth. Grosjean was in contention for his maiden race win in Valencia after an alternator failure forced race leader Sebastian Vettel to retire. Grosjean kept pace with new race leader Fernando Alonso, only to fall victim to the same alternator failure seven laps later. Räikkönen, meanwhile, took advantage of this to finish the race second behind Alonso.