What the sporting regulations say:

  • Unless he drives for more than one team, each driver may use no more than three power units during a championship season. The only exception is where the power unit is provided by a manufacturer or supplier taking part in its first championship season, in which case up to four may be used by a driver.
  • The power unit is deemed to consist of six separate elements: the internal combustion engine (ICE), the motor generator unit-kinetic (MGU-K), the motor generator unit-heat (MGU-H), the energy store (ES), turbocharger (TC) and control electronics (CE).
  • Each driver is permitted to use only three ICE, MGU-H and TC, and only two ES, CE and MGU-K during a championship season and any combination of them may be fitted to a car at any one time. Should a driver use more than that during the course of a season, a grid penalty will be imposed.
  • 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.
  • During any single event, if a driver introduces more than one of a power unit element that is subject to a grid penalty, only the last element fitted may be used at subsequent events without further penalty.
  • If a driver is replaced at any time during the season his replacement will be deemed to be the original driver for the purposes of assessing power unit usage.
  • Teams may only use homologated power units.

What the technical regulations say:

  • The internal combustion engine of a Formula One car must 1.6-litres in capacity and rev-limited to 15,000rpm.
  • The engine must also have six cylinders arranged in a 90-degree formation, with two inlet and two exhaust valves per cylinder and a single turbocharger.
  • Engines exhaust systems must have a single tailpipe for the turbine and either one or two tailpipes for the wastegate.
  • Fuel flow to the engine is limited to 100 kilograms/hour.
  • The use of any device, other than the engine and one MGU-K, to propel the car, is not permitted.
  • The overall weight of the power unit must be a minimum of 145kg. The Energy Store must be installed wholly within the survival cell and must weigh between 20kg and 25kg.
  • The crankcase and cylinder block of the engine must be made of cast or wrought aluminium alloys – the use of composite materials is not allowed. The crankshaft and camshafts must be made from an iron-based alloy, pistons from an aluminium alloy and valves from alloys based on iron, nickel, cobalt or titanium.
  • The MGU-H must be solely mechanically linked to the exhaust turbine of the pressure charging system. The MGU-K must be solely and permanently mechanically linked to the powertrain before the main clutch.
  • A maximum of 4MJ per lap can be transferred from the ES to the MGU-K (and then in turn to the drivetrain).
  • A maximum of 2MJ per lap can be transferred from the MGU-K to the ES.
  • An unlimited amount of energy can be transferred between the MGU-H and the ES and/or MGU-K.
  • With the exception of cars starting a race from the pit lane, the MGU-K may only be used during a race start once the car has reached 100km/h.