The inherent deficiencies of a current internal combustion engine are well known as the basic technology has not changed in 120 years.

For example, ambient air enters the power cylinders, and that air contains dirt which causes wear and contaminates lubricating oil. Similarly, the fuel which enters the power cylinders dissolves lubricating oil, which also causes wear. The optimal mix of air to fuel is called the stoichiometric ratio, however it is impossible to maintain that ratio as the fuel introduced to a conventional engine constantly varies but the volume of air is fixed.  Similarly, when fuel is ignited in the cylinder, combustion is irregular, with a considerable percentage of the fuel never burning. In addition, ¾ of the fuel energy is converted to heat, which must be discharged or the engine will fail, which means ¾ of ones fuel bill is wasted money.

In the quest for higher efficiency and less pollution, a number of alternative powertrains are being considered, however each has its inherent limitations.

In particular, the electric and electric hybrid have garnered the public’s attention although virtually each independent manufacturer has failed now that the “electric rush” is over.

Is the electric vehicle a viable alternative? A global lithium shortage is currently gathering strength, leading the world’s largest vehicle manufacturer to label electric alternatives, including hybrids, as nothing more than “hype”. Electric vehicles are limited by their ability to store energy, and so are limited to niche markets.

hybrid carsAccording to the USA National Research Council, the real health and environmental costs of making electric cars can be 20 percent greater than conventional cars. The study concludes that emissions from operating and building electric cars in 2005 cost about 0.20 cents to 15 cents per vehicle mile traveled. In comparison, gasoline-powered cars cost about 0.34 cents to 5.04 cents per vehicle mile traveled.

In respect to hybrid performance, the Toyota Prius is rated at 50MPG and requires a complete battery change-out every 100,000 miles for $4-5,000. By comparison the VW Polo diesel with the same size motor is rated at 74MPG and is designed to last 250,000 miles.  California may be the Prius capital of the world, but the rest of the world is generally driving diesel, which lasts longer and is more economical.

In respect to electric vehicles, the Tesla purportedly has a 244 mile range. In real world conditions however, using a radio, heater for the cold weather, wipers for the rain, four passengers, stop & go traffic, highway on-ramp acceleration, a few hills, cold batteries, and a rear window defroster then the range quickly drops to 20 miles or less, making the stated range  grossly overstated according to former engineers and company employees.  That is followed by a lengthy battery recharge.

Regardless of the manufacturer, electric will never be a universal replacement for the conventional engine because inherently a battery will never pack enough energy to power anything but niche vehicles. Could an electric 20 ton truck haul its load through the Rockies or the Alps for 1000 miles in competition with an internal combustion engine? It wouldn’t travel 100 meters before running out of battery power.  A ZED powered heavy truck however would retain all the power and range of a conventional engine.

John M. DeCicco holds professorial appointments at the University of Michigan Energy Institute and School of Natural Resources and Environment and is quite clear, “…. electric drive is not the disruptive technology that many green groups and EV buffs proclaim. Putting a battery-based powertrain into a vehicle still defined by a 19th century mobility vision doesn’t make it a 21st century innovation. It just makes it a more costly car and a less capable one at that. Although a small niche will certainly exist, the low volume of EV sales speaks in high volume of its poor business case overall.   EVs do reduce oil use and emissions. However, they are a costly way of doing so, and it’s a myth that getting EVs on the road sooner rather than later is crucial for quickly cutting carbon. The most cost-effective path forward is ongoing fuel economy improvement of gasoline and diesel vehicles….. ”

Another alternative is the electric hybrid, which begs the question “why”. The answer is that an internal combustion engine cannot operate under 800 RPM, and is extremely inefficient until it reaches its most efficient rotational operating speed (typically low load at 2000-2200RPM), delivering very poor fuel economy and considerable pollution.  The electric motor however has a power curve which reaches its highest point at “0”RPM so it is very efficient at low rotational and vehicle speed. As such, it allows an integration of the two power curves, which improves fuel economy and lowers pollution.

In comparison, the ZED engine has a power curve that is virtually identical to an electric motor, as well as the ability to maintain that power up to 6,000RPM like a conventional engine.  As a result it displaces both the internal combustion engine and the electric motor of a hybrid with one ZED engine. The more compact and simple ZED design is far more robust, much lighter and less costly than a hybrid.

For current news and comment on different powertrain technologies, see the “Industry” news section of this web site.