How the Hüttlin Spherical Engine Operates

It seems that with every new hybrid release or update, there's always a minor tweak or enhancement that gives just a slight edge over competitors—enough for marketing to boast about. These incremental improvements are often celebrated, but there's no harm in recognizing that even small contributions to environmental impact and energy conservation can make a real difference.

While such small milestones have been lauded over the years, a German engineer and his Swiss team have been working diligently since before hybrids evolved from being seen as a threat to becoming trendy, and later, mainstream. The result is something truly groundbreaking—an innovation in hybrid technology that no one would have predicted. It's a stroke of genius that the most significant advancement in hybrid tech in years, with roots that go far beyond the current hybrid drivetrain, emerged just when the industry was ready for a fresh burst of innovation.

The Hüttlin engine made its debut at the Geneva Motor Show in March 2011, displayed among other eco-friendly technologies, attracting notable attention due to its unique spherical aluminum design. Let's indulge Dr. Hüttlin and the Innomot AG team, suspending disbelief for a moment and assuming that this design is indeed the most efficient for its purpose. Though the shiny spherical shape might appear unconventional, the science behind it is robust, and the performance statistics are impressive.

The Hüttlin Spherical Engine (also known as the "kugelmotor") offers many advantages of electric vehicles while avoiding some common challenges, such as the limitations of charging infrastructure and the dreaded "range anxiety." This is the widespread fear that a vehicle’s battery will run out of charge before the driver can find a charging station, leaving them stranded. In addition, the typical benefits of hybrid vehicles—like lighter weight, fuel efficiency, and a lower environmental impact—have been enhanced. The Hüttlin Spherical Engine holds promise to elevate hybrid technology, potentially overcoming range limitations and helping electric vehicles gain broader acceptance.

What is a range extender (in automotive terms)?

The Hüttlin Spherical Engine might look a bit out of place rolling around in the engine bay on its own, but don't worry: it was designed as part of a larger system, not as a standalone power unit.

A "range extender" is essentially what separates a hybrid vehicle from a fully electric vehicle. It’s the additional power source that allows a hybrid to exceed the limitations of an electric vehicle’s range. Since range is a primary concern that hinders the widespread adoption of electric cars, this distinction plays a significant role in how these two types of vehicles are viewed.

Finding a reliable range extender isn't as simple as flipping through the pages of men's magazines. In the early hybrid models, the range extender was typically an efficient gasoline engine that aided the electric motor, and the design was much like a conventional engine: an electric generator powered a shaft that set the engine's components in motion, triggering the fuel-burning cycle. Many hybrids still operate this way, though different manufacturers may prioritize aspects like "normality" over efficiency, with the drivetrain engineered to favor one power source over the other. While hybrid technology has evolved significantly in recent years, the basic configurations haven't changed much.

However, now various types of motors are being developed to push the limits of hybrid performance. Some range extenders operate at a consistent pace, while others kick in only when the electric motor requires additional support. Some designs remain fairly traditional, drawing from established automotive technology, while others, as we've seen... well, they're a bit more unconventional.

Dr. Hüttlin and his team introduced a novel design that challenges the established principles of engine construction. Instead of adhering to the standard mechanics (such as the typical shaft and generator configuration), he aimed for a sleek and functional design—one that is largely self-contained and generates its own power. His approach reflects the belief that a range extender shouldn't waste the hybrid's resources; it should be lightweight, compact, efficient, and as affordable as possible. While this isn't a new concept, it inspired him to reconsider the design and perhaps revisit the drawing board.

Reevaluate that concept after reading the next page... and the Hüttlin Spherical Engine may start to seem much less whimsical and significantly more elegant.

Get This Ball Rolling

The Hüttlin is intended to enhance the electrical power of a hybrid car, but for simplicity’s sake, let's assume it’s a standalone engine. In practice, the power it generates is directed according to the hybrid's specific power-sharing system, but for understanding how the motor itself produces power, where it goes afterward is of little concern. Describing this process is complex enough.

Here’s the basic information: The prototype Hüttlin that has been showcased generates about 104 horsepower, but unlike a conventional gasoline engine, Dr. Hüttlin claims the design can easily be scaled to meet various power demands. While modern cars typically use liquid cooling, the kugelmotor can also be adapted for air-cooled configurations. It's made with just a fraction of the parts in a traditional engine—around 60 components in the Hüttlin versus about 250 in a standard four-piston engine. This design helps achieve better efficiency and economy since fewer parts need to be produced and assembled. As a result, the Hüttlin achieves more than 30 percent efficiency—meaning less than 70 percent of the power it generates is lost to heat, noise, and friction, resulting in lower fuel consumption and fewer harmful emissions. In comparison, traditional engines achieve only about 20 percent efficiency. Keep that in mind the next time you fill up.

Now, things get more complicated: The engine's movement, known as "three-dimensional kinematics," includes gasoline combustion and a four-piston setup, but after that, it’s like stepping onto another planet. The engine itself is a head-scratcher—a shiny silver ball with pipes sticking out. It resembles Spaceship Earth at Epcot... but how does this sphere contain what everyone says is inside? Inside the lightweight aluminum globe are smaller kugels running along tracks within the pistons, all mounted on the same bearing inside the rotor, which spins within the outer shell. As the rotor spins, the pistons move in opposition, and the kugels slide along their tracks, causing the rotor to spin. Got it? (The fact that the basic components share names with traditional engine parts only adds to the confusion.)

Along the way, some coils and magnets generate power, which is then transferred outside the sphere to a set of batteries. These batteries act as temporary storage, moving the power along the drivetrain as needed. The power is sent to another motor that directly drives the wheels, bypassing the traditional drivetrain. Innomot AG claims that this setup is more efficient.

Dr. Hüttlin has mentioned that developing the kugelmotor took him and his team several decades to perfect, but he anticipates seeing it in production vehicles within the next 2 to 5 years. The patents for the technology were filed in December 2010, adding to Dr. Hüttlin's extensive portfolio of over 150 patents. Innomot AG intends to license this technology, so the Hüttlin could soon be a key component in the engine bays of various hybrid vehicles.