It may sound like science fiction, but the concept of a jet turbine engine powering a mainstream car is closer to reality than many realize. Historically, cars equipped with aircraft engines have existed, with more than a dozen documented examples, and Subaru may soon join this exclusive club. Recently, the World Intellectual Property Organization (WIPO) published a filing revealing that Subaru has patented an electric power system and startup control method for a turbine engine, potentially designed for everyday electric vehicles (EVs). Notably, this is not Subaru’s first foray into turbine-powered EVs; a previous patent, filed last year, explored using a turbine engine to extend electric vehicle range.
Subaru’s Turbine Patents Target Extended-Range EVs
The two patents, highlighted by CarBuzz, focus on using a turbine as a steady-state generator rather than a direct propulsion system. In the first patent, Subaru addresses the challenge of long turbine spool-up times, proposing a method to start the engine quickly. By overcoming this limitation, the turbine could efficiently generate electricity to feed an extended-range EV (EREV), potentially offering a more efficient alternative to traditional internal combustion engines.
The second patent tackles another critical issue: ensuring the turbine can start and generate power even if it initially loses energy or cannot reach operating speed as quickly as needed. According to the filing, the system is designed to work symbiotically with the EREV’s batteries. When the high-voltage battery has sufficient charge to drive the vehicle at full power, it can rapidly spin up the turbine via the electric motor-generator. When the high-voltage battery is low, the 12-volt battery can slowly start the turbine, preventing full depletion while still enabling the generator to operate.
Potential Advantages and Challenges
Unlike aircraft turbines that rely on compressed air to start, Subaru’s system uses the existing electric motor in the EREV, simplifying the design. The turbine would be smaller and lighter than conventional jet engines, allowing even the 12-volt battery to reach target speeds. However, the addition of a turbine introduces extra weight, a challenge for any EV. Furthermore, if the vehicle is completely depleted of power, it would require plugging in to restart, as there would be no external airflow to spin the turbine.
Noise management is another consideration. Subaru’s patent suggests starting the turbine at 20,000 rpm using the 12-volt battery and 25,000 rpm using the high-voltage battery. Given the turbine’s small size, engineers could likely insulate it effectively, mitigating potential noise concerns.
While this concept remains a patent and may never make it to production, it represents a bold exploration of how jet turbine technology could enhance EV efficiency. If realized, Subaru’s turbine-powered EREV could redefine the future of its performance-oriented STI lineup, attracting attention for its innovative approach to extending electric range.
