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Hybrid Vehicle Fuel Economy without Electrification? – Namikoshi Electronics

Namikochi Electronics' Four-Cylinder Engine Concept Could Deliver the Fuel Economy of a Hybrid Vehicle
Namikochi Electronics’ Four-Cylinder Engine Concept Could Deliver the Fuel Economy of a Hybrid Vehicle

Improving fuel economy can be done in a number of ways, not all of which require electrification.

The internal combustion engine (ICE), although over one hundred years in the making, is woefully inefficient when it comes to converting the stored energy in a fuel into usable energy. Even the best engines are a mere 25-30% efficient, which is why ICE-driven conventional vehicle fuel economy tops out at 40 mpg (miles per gallon). These vehicles, however, can only hold a couple of people, limiting their usefulness for the typical driver. They also are nowhere close to the 54.5 mpg, by 2025, CAFE (Corporate Average Fuel Economy) standard necessary to reduce carbon dioxide emissions.

Vehicle electrification seems like it could be the next best thing to boost fuel economy to meet the 2025 CAFE standard, but even hybrid vehicles top out at 50 mpg. It is closer, and future technological improvements are sure to bump that fuel economy number higher. On the other hand, hybrid vehicle technology also costs more and could possibly be even less cost-effective than a conventional vehicle, given possible battery replacement or hybrid battery conditioning costs.

Namikoshi Electronics, of Japan, figures that a new ICE design might deliver the performance and fuel economy of a hybrid vehicle without the expensive electric motor-generators and NiMH or Li-ion (nickel-metal hydride or lithium-ion) hybrid battery pack. The key to the new four-cylinder engine design looks kind of like a cross between a Subaru boxer engine and the Waissi Engine, but with major improvements in friction-reduction. The typical inline four-cylinder engine, even the Subaru boxer, has a lot of friction points, between the block and crankshaft, crankshaft and connecting rods, and connecting rods and pistons, all of which robs the engine of power and efficiency.

The Namikoshi 1.5 ℓ engine has two pairs of opposing cylinders, all fixed to a single point on the crankshaft. The idea is to reduce all those typical friction points to just one or two. The rest are eliminated simply because the parts are eliminated, and smooth-rolling ball-bearings eliminate the rest. Namikoshi Electronics says the new ICE concept could have the fuel economy of a hybrid vehicle, due to friction- and weight-reduction measures alone, but still has not released any hard data. Looking forward to seeing more on this concept.

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  1. lad2 True enough. There have been a number of ICE designs that seem very promising in reducing fuel consumption, but too late in the game. While I would love to see them eliminated, market forces and public opinion still is not on my side, so ICE-driven vehicles will still dominate for decades. Sad, but true.

  2. There are a lot of IC engine designs; all suffer from the same problem….they burn hydrocarbons in the atmosphere.

    This is another very interesting mechanical engineering experiment that will likely never reach production; nevertheless, it is useful in demonstrating what could have been accomplished had efficiency been a past priority.  Now, it is an obsolete technology and will be displaced in most cases by electric motors.


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