Beginning in 2026, Formula One will adopt a radically revised power unit architecture. F1Technical’s senior writer Balazs Szabo analyses how track characteristics might influence the performance of the various power units.
The internal combustion engine remains a 1.6-litre turbocharged V6, but the MGU-H — the component responsible for harvesting energy from the turbo — will be eliminated.
In its place, the MGU-K will take on a significantly expanded role, with electrical output increasing to 350 kW, nearly double the current figure. This shift places far greater emphasis on kinetic energy recovery under braking, making the driving phase distribution of each circuit a critical factor in power unit performance.
Circuits with long braking zones and frequent deceleration events — such as Monaco, Singapore, and Hungary — will offer more consistent energy harvesting opportunities.
However, tracks dominated by full-throttle running and minimal braking — such as Monza, Jeddah, and Spa — may present challenges in maintaining battery charge levels. Without the MGU-H to supplement harvesting from the turbo, teams will need to optimise MGU-K deployment and recovery strategies with greater precision.
Additionally, the 2026 regulations mandate the use of 100% sustainable fuels and introduce tighter constraints on fuel flow and energy deployment windows. This will further amplify the strategic complexity at circuits with variable throttle profiles, where energy harvesting and deployment must be balanced against fuel efficiency and thermal management.
What does the data reveal about the current circuits?
The driving phase data from 2025 – provided by F1DataAnalysis – not only reflects the diversity of the current calendar but also foreshadows the strategic and technical challenges teams will face under the 2026 power unit regulations.
As the sport transitions to a more electrified and sustainable era, the ability to harvest and deploy energy efficiently — especially at circuits with limited braking — will become a decisive factor in race performance and power unit competitiveness.
The breakdown of driving phases — braking, neutral, partial throttle, and full throttle — across the 2025 Formula One calendar offers a look into the mechanical and aerodynamic demands of each circuit. These percentages not only reflect the character of each track but also influence setup direction, energy recovery strategies, and tyre degradation profiles.
At the top of the full-throttle spectrum are the Italian and Saudi Arabian Grands Prix, with 77.6% and 76.1% of lap time spent at maximum throttle, respectively.
These figures underscore the high-speed nature of Monza and Jeddah, both of which feature extended straights and flowing corner sequences that allow sustained acceleration.
In Monza’s case, the low-downforce setup and minimal cornering load make it the most power-sensitive venue on the calendar. Jeddah, while technically a street circuit, behaves more like a high-speed track, with rapid directional changes and minimal braking zones.
Conversely, Monaco sits at the opposite end of the spectrum, with just 44.0% of lap time spent at full throttle and a braking phase that accounts for 20.8% — the highest of any circuit. This reflects the circuit’s stop-start nature, tight corner radius, and low average speed. The high proportion of braking and neutral phases at Monaco places extreme demands on brake cooling and energy recovery systems, while also limiting opportunities for aerodynamic efficiency.
Other circuits with relatively low full-throttle percentages include Mexico City, Singapore, and Hungary. These tracks feature complex corner sequences and short straights, which reduce the time spent at wide-open throttle and increase the importance of mechanical grip and traction. Singapore, in particular, combines high braking demand with a long race duration, making it one of the most physically and technically challenging events of the season.
Midfield circuits such as Bahrain, São Paulo, and Texas offer a more balanced distribution. These tracks typically feature a mix of high-speed sections and technical complexes, resulting in full-throttle usage in the 60–70% range. This balance allows teams to explore hybrid setup philosophies, blending aerodynamic efficiency with mechanical compliance.
From a strategic perspective, circuits with high full-throttle percentages tend to favour lower downforce setups, aggressive ERS deployment, and reduced tyre stress, particularly on the rear axle.
In contrast, tracks with high braking and partial-throttle phases demand robust brake management, precise throttle modulation, and greater emphasis on traction zones. These characteristics directly influence tyre compound selection, pit stop windows, and energy recovery calibration.
