The F1 power unit explained: six parts and a grid penalty
Six sealed components make up every F1 engine, and in 2026 the FIA tore up the recipe that had stood since 2014.
By Indy GillWatch a driver drop ten grid places on a Saturday with no crash and no red flag, and you're watching the power unit rules bite. Somewhere in a garage a mechanic fitted a fourth turbocharger when the driver's allocation only stretched to three, and the FIA's ledger did the rest.
A modern F1 power unit isn't one engine, it's a family of components, each sealed, each tracked, each counted against a season allowance. Get your head around those parts and the whole strategic subplot of engine penalties, manufacturer rivalries and the 2026 rulebook rewrite starts to make sense.
Why a fan needs to know this at all
The power unit is the reason Honda came back to the grid, the reason Audi arrived for 2026, and the reason a driver can top every practice session and still start twenty places down the order on Sunday. When commentators talk about a team being "in trouble with its pool" or a manufacturer running its final-spec engine, this is the system they mean, and it rewards patience as much as raw horsepower.
Six parts, one job: the 2014 to 2025 recipe
Strip away the branding and the hybrid-era power unit reads like a short parts list. The internal combustion engine is the familiar bit, a 1.6-litre V6 turbo spinning to around 15,000rpm, small enough to fit under a wasp-waisted engine cover but tuned to punch far above that capacity. Bolted to it is the turbocharger, forcing extra air in to make that small block breathe like something twice the size.
Then come the two motors that made this era genuinely different from anything before it. The MGU-K sits on the crankshaft, harvesting energy under braking and firing it straight back in on acceleration, a seamless boost the driver barely has to think about. The MGU-H was the cleverer, stranger cousin, bolted to the turbo shaft rather than the crank. It pulled energy out of the exhaust gases before they'd finished spinning the turbine, using that surplus to spin the turbo up faster and effectively erasing turbo lag. It was also the single most expensive, most patent-protected piece of engineering on the car, which is exactly why it isn't sticking around.
The last two elements don't make power, they manage it. The Energy Store is the battery pack, storing what the MGU-K and MGU-H recover so it can be deployed again a corner or two later. The control electronics are the brain, the box that decides how much energy goes where and when, keeping the whole system from either stalling the engine or cooking the battery. Put all six together well and the numbers were startling for a 1.6-litre unit: over 1000 horsepower combined, at a thermal efficiency road-car engineers would sell a kidney for.
The allocation game: why grid penalties happen
Here's the part that actually shows up on a Saturday timing screen. The FIA doesn't let a team build a fresh engine for every weekend; it homologates a fixed dossier of parts at the start of the year and seals every element that goes into it, so nothing gets quietly rebuilt mid-season. Sporting Regulations Article B8.2.2 sets the baseline pool for a full championship: three ICEs, three turbochargers, three exhaust sets, two energy stores, two control electronics units and two MGU-Ks, with a looser allowance of five for the small ancillary parts. Article B8.2.3 then grants an extra unit of each in the 2026 championship specifically, and to any manufacturer supplying power units for the first time, which is why the numbers you hear quoted trackside sometimes sit one higher than the regulation's own baseline.
Go over that allowance and Article B8.2.8 has a table waiting. The first time a driver introduces an extra unit of any element beyond their pool, it costs ten grid places at that race; every further infringement after that costs five more, and the penalties stack without a cap. A team that's burned through its ICEs and energy stores and then needs a fresh turbocharger too can watch a driver's grid slot unravel by twenty places or more before a wheel has turned in anger, which is precisely the scenario that produces those baffling grid sheets where a genuinely quick car starts from the back.
Article B8.2.9 is the enforcement behind all of it: the FIA physically seals ICE, turbocharger and MGU-K elements after use so nothing can be cranked, let alone rebuilt, between events without the seal being broken under FIA supervision. Break a seal without permission and that component simply can't be used again. It's less romantic than a strategy call on lap 40, but it shapes a season just as decisively; a manufacturer nursing a fragile engine through its final races is fighting this ledger as much as it's fighting the car in front.
2026: no MGU-H, and a very different balance
The 2026 regulations don't tweak this recipe, they rewrite it. The MGU-H is gone entirely, judged too expensive and too disconnected from any road-relevant technology to justify keeping. In its place, the MGU-K takes on a vastly bigger share of the workload, its power output roughly tripled compared with the outgoing unit, so that electrical power supplies something close to half the car's total output rather than the smaller slice it managed before. The internal combustion engine survives largely unchanged in its basic architecture, still a 1.6-litre V6 turbo, but it will burn fully sustainable fuel rather than the blended fuels used through the 2020s, closing off one of the last arguments critics made about hybrid F1's relevance to the road.
Losing the MGU-H changes more than the parts bin. Without it recovering energy from the turbo, engineers have to find another way to keep the turbocharger spinning fast enough to avoid the lag that plagued turbo cars before hybrid recovery existed, and battery deployment strategy becomes a bigger lever on lap time than it's ever been. Expect the first year or two of the new formula to produce power units that behave noticeably differently out of slow corners, with electrical deployment doing more of the visible work and the sound, already softened once by the V6 switch, changing again.
Where you'll actually see this argument play out
Watch for it whenever a team announces it's taking a new-specification engine mid-season; that's a manufacturer judging that a grid penalty now is worth a genuine step in performance for the races that follow. Watch for it in a driver's championship battle too, where a rival's fresher power unit late in the year can matter as much as a wet qualifying session. And when 2026 arrives, watch the exit speeds out of hairpins first; that's where a power unit with no MGU-H and a much bigger battery is going to look and sound like nothing that's raced before it.
For the individual pieces in more depth, the energy store, the MGU-K and the departing MGU-H each get their own explainer, and the grid penalty mechanics sit alongside the engine allocation rules for anyone chasing the full paper trail behind a driver's grid slot.