Inventor Hilberg Karoliussen
The Hilberg Engine

How was Hilberg Karoliussen, resident in the small port of Arendal on Norway’s southern coast, able to crack the code?

The answer lies in a combination of special personal qualities and many years of experience from the Norwegian petroleum sector and the Swedish car industry.

Karoliussen has 12 patents to his name, including several related to the oil industry. As early as the 1980s, he came up with the concept of a new type of crankshaft when designing a vibration-free compressor for large industrial plants. He developed this further to meet the need for a powerful vibrator to stress-test piping systems on oil platforms. Nevertheless, it was not until much later that he produced the first detailed drawing of what has become the revolutionary crankshaft in the Hilberg Engine.

After studying efforts to overcome the challenges of variable compression by the car industry, Karoliussen observed a common denominator – it was trying to modify 19th-century technology instead of designing an engine from the ground up.

He agreed with the view of the motor manufacturers that it would be impossible to meet the EU’s radical emission-reduction demands with the existing technological approach. In 2016, he realised that his crankshaft offered the solution to the basic problem with the internal combustion (IC) engine after the Euro 6 directive – combining efficiency with lower emissions.

Karoliussen quickly developed digital models which were eventually 3D-printed at a reduced scale before the first working metal prototype was produced in great secrecy. This functioned entirely as predicted in digital simulations. Tests also showed that the solution was extremely quiet.

He had designed an engine with almost no moving parts, which was much smaller and lighter than existing types and at least 30 per cent more efficient.
Developing the Hilberg Engine demonstrates our unique understanding as a company of the dynamic interaction between requirement and solution, and our ability to think along radically different lines about existing technology.

Century of technological stagnation over

In 1920, motor fuel was not standardised and octane ratings unknown. This meant each engine had to be fine-tuned after refuelling to achieve the right compression. British engine pioneer Sir Harry Ralph Ricardo grasped that this problem could be overcome with variable compression. He built an engine where the driver could mechanically raise or lower the crankshaft as and when required.

Although a drawback of this solution was that the engine became heavy, the principle had nevertheless been demonstrated and was ready for the kind of evolution all engine principles undergo. But another possible solution to the compression problem was available, which brought the development of variable compression to a halt.

Standardised motor fuel, with an octane rating tailored to different models, became the universal answer to one of the major challenges facing the IC engine. In other words, the need for variable compression disappeared and this area of engine technology stood still for decade after decade. It was the fuel which evolved down to the present day. The 20th century has few, if any, more obvious cases of technological stagnation than the failure to develop compression capability in IC engines.

Changes nevertheless occurred to supply and demand for motor fuel during the last century. The 1973 oil crisis emphasised the need to develop more economic engines which got more out of the fuel. But it was the Euro 6 directive which really gave the industry a pressing need – without an answer. The mechanical solutions attempted were either unstable or too heavy.

Their common denominator was that they all started from existing engines. Extensions to connection rods, different tilting or hydraulic systems – all these approaches failed because they did nothing fundamental with the engine’s design. In principle, this had remained unchanged since the 19th century. The result was mechanically complex engine systems with many components and insoluble problems.

Out with the old

Karoliussen opted for the opposite strategy and designed a new engine principle involving very few moving parts and a new type of crankshaft.
Scarcely numbering more than pistons and shaft, these moving parts act as counterweights and balance each other so that the engine is virtually vibration-free. Its weight has also been greatly reduced, and it is more efficient than existing types. This engine is the first to utilise both a variable compression ratio and double expansion.

Karoliussen has not improved existing designs, but created a new type of IC engine from the ground up. The few existing multifuel car engines – which can run on various types of fuel – all make comprises which increase weight and reduce efficiency. But multifuel operation is a natural consequence of the unique Hilberg Engine solution – without any compromises.