Hybrid Ratings

Last Updated: Mon. 4/18/2005
 

Some people will lead you to believe that all hybrids are equal, misrepresenting them simply by not providing detail.  Don't allow that to happen. 

The following is an example of how points could be awarded based on merit, by clearly identifying useful the abilities a hybrid provides.  Just add up the values that apply to the hybrid you are analyzing.  (Note that some topics are mutually exclusive, like emissions & cooling.)  Or just use it as a guide to help raise awareness about the differences in design among the various hybrids.
 

Point Value

Topic

Detail

0 Engine Shutoff

Since this is available on a small number of traditional vehicles (those that do not offer any thrust at all from an electric motor), it shouldn't be considered a hybrid feature.

0 Cylinder Deactivation

Since this is available on a small number of traditional vehicles (those that do not offer any thrust at all from an electric motor), it shouldn't be considered a hybrid feature.

1 SULEV

This emission rating is the new baseline for clean vehicles, both traditional & hybrid, since a large number of vehicles (Car, Pickups, and SUVs) already deliver the less clean ULEV rating.  For a hybrid to be considered a benefit to smog reduction, it must achieve SULEV.

2 PZEV

This emission rating is actually SULEV with one additional type of pollution reduction, the elimination of evaporative emissions.  This is not a type of that comes out of the vehicle's tailpipe from the engine; instead, it comes from the gas tank.

1 Mild electric cooling

Limited A/C and Window-Defrosting using only electricity.

2 Full electric cooling

Full A/C and Window-Defrosting using only electricity, absolutely no mechanical assistance from the engine to drive a condenser.

1 1-25 MPH stealth

This level of electric-only driving is beneficial during stop & slow traffic, common for those having to endure a daily commute with very heavy congestion on the highway.

1 30-40 MPH stealth

This level of electric-only driving is beneficial in city & suburb type roads.

1 45-55 MPH stealth

This level of electric-only driving is beneficial on residential thruways and on local highways.

1 60-75 MPH stealth

This level of electric-only driving is beneficial on fast, constant, high-speed type driving on roads like freeways, beltways, and expressways.

1 Create & Consume

The ability to both create & consume electricity simultaneously is a significant benefit for extending the life of the battery-pack (by using electricity from the generator instead) and a benefit for ensuring that an ample supply will always be available (by using surplus electricity for recharging).  The ability is possible due to having a power-split-device and 2 motor/generators; not all hybrids do.

 

This unique approach to judging merit does not ignore MPG; instead, it focuses attention on those abilities that provide increased efficiency.  The reason for this is that far too many people only base worth on reports of MPG alone, rather than looking closely at the what the design itself actually provides.  This is very important since data can easily be misrepresented by giving you the impression that it applies to all real-world conditions you will actually encounter when it really only identifies a particular type of driving under certain conditions.

 

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