F1 Explained: Why are engines limited? Are the rules different for 2018?

Engine penalties have been a divisive issue in recent seasons, with teams struggling for unreliability in the hybrid era often having races wrecked when they take on new power-unit components. McLaren know about this more than most! But what's the deal with the system? Why do we have it, and what's new for 2018? Here are the answers.

WHAT IS THE ENGINE LIMIT?

F1's rules say: "Each driver is permitted to use only a limited number of power unit elements – of which there are six types – during a single season. 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). Should a driver use more than this, a grid penalty will be imposed."

WHY ARE THE LIMITS IN PLACE?

Chiefly, to cut the spiralling costs involved in running an F1 team. Mercedes and Ferrari could probably afford to put a new engine in their car every race, but other teams cannot. This also helps level the playing field, somewhat.

WHY ARE THE PENALTIES SO HARSH?

They were under the previous rule set, which added penalties on top of each other. This led to some pretty farcical situations. At the 2017 Italian Grand Prix many teams chose to use penalties tactically, which led to chaos after qualifying.

Sergio Perez qualified 11th, was given a five-place penalty, but started 10th on the grid. Confused? We all were.

Thankfully, it's a bit simpler now...

SO WHAT ARE THE PENALTIES NOW?

Again, from F1: "The first time a driver uses an additional element over and above the prescribed limits, a ten-place grid penalty will be given. If he then uses other additional elements a five-place penalty (or penalties) is imposed. Use yet a further example of any given element and another ten-place penalty is received – and so on."

So, in essence, drivers who need a fourth element in the season will receive a 10-place grid drop. Need a fifth, or more, and it'll be five, unless you're changing more than one component, which will land you a 10-place penalty.