Horse Powertrain and Repsol unveil ultra efficient hybrid engine
The new HORSE H12 Concept engine increases vehicle efficiency while reducing fuel consumption by 40%.
Horse Powertrain and Repsol have developed a next‑generation hybrid engine capable of operating on 100% renewable petrol, marking a significant step in Europe’s efforts to cut transport‑sector emissions. The new HORSE H12 Concept engine increases vehicle efficiency while reducing fuel consumption by 40%, dropping below 3.3 litres per 100 km under WLTP testing.
According to the companies, a medium‑sized car equipped with the engine and powered by Repsol’s fully renewable fuel would emit 1.77 tonnes less CO₂ per year than a comparable vehicle using conventional fuel. The engine reaches a maximum thermal efficiency of 44.2%, achieved through advances in combustion design, a 17:1 compression ratio, next‑generation EGR technology, an optimised turbocharger and a high‑energy ignition system. Improved hybrid transmission management and low‑friction lubricants developed by Repsol further contribute to efficiency gains.
Developed by Horse Technologies in Valladolid and Repsol’s Technology Lab in Madrid, the project has completed its first two prototypes, with a demonstrator vehicle expected in early 2026. Both partners describe the initiative as evidence that European industrial innovation can deliver short‑term CO₂‑reduction solutions alongside electrification and hydrogen technologies.
Repsol supplies renewable diesel at more than 1,500 service stations across Spain and Portugal, making it the largest distributor of renewable fuels in Europe.
