Despite the performance gains achieved by Honda and Renault, the Japanese and the French manufacturer are yet to make inroads when in comes to the reliability and durability of their complex hybrid power units. In our latest review, Balázs Szabó looks back at the power unit useage by the different engine-manufacturers in the 2019 season.

Formula One rewrote the engine regulation for the 2014 season by introducting complex hybrid power units. As the regulation came into force, Mercedes shocked its rivals, Ferrari and Renault with its powerful and reliable product and enjoyed a competitive advantage for a couple of seasons. However, Ferrari has managed to make gains, investing heaviliy into the development of their hybrid power unit.

Renault and Honda which rejoined the sport in 2015 found it particularly hard to get up to speed and keep up with the incredible development pace of the two leading manufacturers. However, as the power unit regulation remained stable, Renault and Honda could make inroads, prompting suggestions that the duo could reach the level of Mercedes.

Renault team boss Cyril Abiteboul went so far as to say that his team has caught up with Ferrari and so has the best power unit along with the Italian outfit.

"According to our measurements, Ferrari and we currently have the most powerful engines in race trim. Then comes Honda and then Mercedes," said Abiteboul, quoted by Auto, Motor und Sport.

In contrast to that bold claim, Mercedes engine boss Andy Cowell suggested that the German engine-maker is on a similar level to that of Renault and Honda while Ferrari enjoys a competitive advantage. "The differences between Honda, Renault and us are minimal. Only Ferrari currently stands out", insists Cowell.

Mercedes with the most reliable products

With the introduction of the hybrid engines, it became rather difficult to assess the quality and competitiveness of a power unit. There is a significant difference in qualifying and race settings and the heavily limited number of units put emphasis on the durability and reliability of the engines.

During the 2019 season, each driver is permitted to use only a limited number of power unit elements – of which there are six types. The limits are three ICE (internal combustion engine), MGU-H (motor generator unit-heat) and TC (turbocharger), and two ES (energy store), CE (control electronics) and MGU-K (motor generator unit-kinetic).

When analysing the power units in terms of durability showed in the 2019 season, it is vital to stress that Ferrari and Mercedes supply six cars with their product while only four cars are driven by Honda and Renault power units.

In terms of internal combustion engine, Ferrari proved the most reliable while Mercedes had a few technical issues mainly on the cars of Valtteri Bottas and Sergio Perez. It is also worth noting that the works Mercedes outfit installed two fresh internal combustion engines in to the car of their Finnish driver to conduct while conducting experiments on engine components and solutions aimed at the 2020 season.

Honda used the highest amount of ICEs during the season. The high amount of engines was partly down to reliability issues which arose around the mid-point of the season and partly down engine experiments after the summer break when Red Bull introduced three new ICEs over the period of four grands prix.

Mercedes stand out with the reliability of their control electronics while that proved to be an Achilles heel for Ferrari and Renault. On the contrary, Mercedes experienced issues of different nature with their turbocharger during the season, prompting them to exceed the limit with Valtteri Bottas, Sergio Perez, Lance Stroll and Robert Kubica.

When it comes to the drivers, only two drivers – Lewis Hamilton and Romain Grosjean - managed to complete the season without taking a penalty for extra power unit components. The most thirsty car belonged to Daniil Kvyat who used a total of 33 power unit components instead of the maximum number of permitted parts of 15.