What to criticize about a hybrid engine with 100% renewable fuel?

Horse and Repsol present a hybrid engine running on 100% renewable gasoline, ensuring a significant reduction in CO2 emissions.

Horse Powertrain and Repsol have introduced the HORSE H12 Concept, a next-generation hybrid engine designed to combine high energy efficiency with low emissions, while utilizing 100% renewable gasoline. According to standardized WLTP tests in Europe, this engine reduces the consumption of an average vehicle by nearly 40%, bringing it down to less than 3.3 l/100 km, which concretely illustrates the positive impact of hybrid solutions and renewable fuels on mobility.

The combination of this engine with fully renewable fuel technology also significantly decreases CO2 emissions. A vehicle equipped with the HORSE H12 Concept and averaging 12,500 kilometers per year would emit 1.77 tons of CO₂ less than an equivalent vehicle with a traditional engine. These results demonstrate that innovation in hybrid engines and alternative fuels can achieve tangible gains today, in addition to electrification and other low-carbon technologies.

Electric-only is no longer the sole future solution

The HORSE H12 Concept is based on an evolution of the HR12 engine and incorporates major innovations in combustion and energy management, including a high compression ratio, an optimized exhaust gas recirculation system, and a next-generation turbocharger. The combination of these technologies allows for a maximum thermal efficiency of 44.2%, while reducing internal friction through lubricants developed by Repsol. These enhancements, integrated into an optimized hybrid transmission, illustrate the European industry’s ability to produce concrete solutions to reduce emissions in the short term.

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Innovation

• 17/02/2026 14:17

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The project, conducted from Valladolid and the Repsol technological laboratory in Madrid, has already produced its first two prototypes and validated the engine’s performance. The first demonstration vehicle will be unveiled at the beginning of 2026, marking a decisive step towards the industrial production of highly efficient hybrid engines. For the teams at Horse Technologies and Repsol, this initiative proves that a technologically neutral approach, combining high-performing engines and renewable fuels, can contribute today to the transition to carbon-neutral mobility while preparing Europe for a low-carbon and innovative future.

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