American inventor Herns Louis has come up with an interesting way to reduce inefficiencies inherent in regular dual-fuel motors. His H-motor design features two cylinder banks, each running on a single fuel source – so the left can be tuned for power and efficiency on gasoline, and the right can be tuned for CNG.

Dual fuel engines are nothing new; my first car nearly 20 years ago was a canary yellow Holden Kingswood that ran either Liquid Petroleum Gas (LPG) or petrol, and I'd happily fill up the LPG tank for less than seven dollars. Happier times!

But engines designed to run on multiple fuel sources are compromised; they must be tuned to suit one fuel or the other, or something in between, and this can end up leading to significant power and efficiency losses.

That's the thinking behind Eco-Motive's new engine, which inventor Herns Louis is calling "the world's first dual-fuel 'H' power plant."

This engine design, which Louis says can be adapted to run with "any internal combustion engine with an even number of cylinders," is actually effectively two engines, because each bank of cylinders is set up to run solely on a single fuel source.

Thus, the left bank can be tuned to maximize power and efficiency for petrol, and be fed from the petrol tank, and the right bank can be tuned for Compressed Natural Gas (CNG) and run from the CNG tank.

Each side is controlled by an engine selector gearbox, which connects to the main transmission. The driver chooses which engine is running with a switch, and there's one fuel filler cap on either side of the car, which … could get a bit annoying.

There's no mention of running both sides of the H-engine concurrently for maximum power, so any efficiency gains will have to be significant to offset the weight penalty of an extra cylinder bank.

We're not sure we agree with Louis that the H-motor is "a leap forward that is as revolutionary as Henry Ford's adoption of the assembly line," but it's certainly an interesting idea.

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