Why 'power unit', not 'engine'
Since 2014, F1 cars are propelled by hybrid systems: a 1.6-liter turbocharged V6 internal-combustion engine plus electrical machinery that recovers, stores and redeploys energy. The complete package — engine, motor-generator, battery, turbo and control electronics — is the 'power unit'.
The 2026 regulations rebalanced it dramatically: electrical power roughly triples to ~350 kW, making the split between combustion and electric power close to 50/50. The MGU-H (turbo energy recovery) was dropped to cut cost and complexity.
Sustainable fuel
From 2026 all cars run 100% sustainable 'drop-in' fuel — synthesized without adding new fossil carbon, and usable in principle by ordinary road cars. This was the headline demand that attracted Audi, Honda's return, and Ford's partnership with Red Bull.
Fuel-flow limits, not displacement, cap engine power. Efficiency is the competition: F1 engines exceed 50% thermal efficiency, the highest of any production-adjacent combustion engine ever built.
Managing the battery
Drivers and their engineers manage electrical deployment lap by lap: harvest under braking, deploy on the straights that matter. With half the power now electric, energy management is as decisive as raw horsepower — running out of battery mid-straight is the new running out of breath.
The 2026 rules add a 'manual override' mode giving attacking cars extra electrical deployment when close behind a rival — the spiritual successor to DRS.
Reliability and penalties
Each driver gets a limited allocation of power-unit components per season; exceeding it triggers grid penalties. This is why you'll see teams strategically take a 'penalty weekend' at a track where overtaking is easy, banking a fresh engine for the run home.
Manufacturers — Ferrari, Mercedes, Honda, Red Bull Ford, Audi — supply themselves and customer teams, and a winter of engine development can reorder the entire grid.