BTCC drops hybrid to mandate 100% sustainable fuel from 2025

Power boost to come solely from turbo as ‘green’ focus switches

The British Touring Car Championship has dropped hybrid and introduced 100% sustainable fuel for the 2025 season.

The Cosworth-developed hybrid was introduced for the 2022 campaign, with restrictions on its usage for the leading contenders in the championship allowing BTCC organiser TOCA to drop its previous success-ballast system.

For 2024, the ‘push-to-pass’ hybrid was augmented by an equivalent power boost from the engine turbo, meaning the increase from usage was effectively doubled to approximately 60bhp.

From 2025, the power boost will remain the same but will come solely from the turbo.

Simultaneously, the BTCC has balanced its ‘green’ credentials with the mandatory usage of 100% sustainable fuel – up from the 20% mixture used this season – as trialled successfully by the Unlimited Motorsport Cupra Leon of Daryl DeLeon at the final two rounds.

TOCA boss Alan Gow told Autosport that the moves came with the full support of the teams.

“We had a teams’ meeting last week,” he said. “Very few regulation changes happen without discussing them first with the teams.

“This year the hybrid was fantastic. The first year with any new technology is always challenging, but after that it was fine [in 2023 and 2024].

“This year, we upped the amount of output combining the hybrid and the turbo and there were no problems at all – we like what it delivered.”

Although the reliability of the hybrid improved significantly since its introduction in 2022, teams were concerned about the cost from running the system, although Gow denied that this played a part in the decision to drop it.

“You can do a lot of things to save money,” he said. “This is merely a change in direction.”

Cosworth will still keep its involvement in the BTCC via its supply of the control electronics system, while the removal of hybrid will reduce the weight of the cars by 55kg.

“Six years ago, when we first announced hybrid, it was a technology still in its relative infancy within motorsport,” said Gow.

“We’ve successfully completed that programme – and really have no more to prove in that respect – whilst others have yet to catch up.

“But, as we’ve now ticked that box we can move further forward with the introduction of fossil-free sustainable fuel, whilst delivering the same performance parameters.”

The sustainable fuel programme “has been going on for three years”, said Gow, who added that all the BTCC engine suppliers have had the latest iteration for the past few months for testing on the dynamometer.

“That’s why we ran it in Daryl’s car for the last two events,” said Gow, “and they’ve done a lot of testing [including two days on track] since then to validate everything we thought we knew about the fuel.

“ATL, who do the fuel systems, have also had it to make sure there are no negative effects on seals, lines and tanks.”

Gow added that the sustainable fuel – named Hiperflo ECO102 R100 – is the direction to head in, especially in the wake of Motorsport UK’s announcement on the same topic this month.

“You can’t do everything, and frankly there’s no need to,” he said. “Our purpose is better suited by focusing on fully sustainable fuel, and the power delivery from the hybrid will be replaced by extra power delivery from the turbo.”

This, in turn, means that hybrid can be abandoned without the prospect of returning to the old pre-2022 days of success ballast.

“That’s what I wanted to avoid,” he said. “The easiest thing to do is whack a load of lead in the car, but we’ve moved on from those days.”