Comments on: Hybrid Leaders Pass Major Milestones

By: Shines

Shines — Thu, 12 Mar 2009 17:08:15 +0000

This article is about almost 1.5 million hybrid sales. Way to go Ford, GM, Honda, Nissan,Toyota. This is a very positive step in the right direction.
As far as materials, coefficients of drag, and other technologies, the manufacturers have to weigh these against manufacturing costs, current fuel costs, the economy, buyer incentives and even politics to decide which technologies to implement. The original Honda Insight is a perfect example. It got almost 70 MPG yet few people bought it because even though it was relatively efficient it was too small, uncomfortable and poorly styled. So even though we may desire fuel efficiency and function over form, people still want to look good as well as feel good about the cars they own.
The best incentive I can think of to get more people considering greater fuel efficiency is fuel cost. Simple economics work best.

By: rc55

rc55 — Thu, 12 Mar 2009 15:21:56 +0000

Ross,
What science are you using for this statement? No open wheel wells? How do you plan on changing a flat tire??? Or turning the vehicle? And what the hell is Boat-tailed? We all know how efficient a boat is! So the vehicle is too heavy, yet you want to add more weight with a belly pan???? Wheel diameter and especially widths, also have an effect on vehicle stability and traction to the roadway, not just for optimums! If you want optimums, figure out how to use a sphere!
Next time think before you speak, and don't speak for me!!!

By: Lost Prius to wife

Lost Prius to wife — Thu, 12 Mar 2009 15:16:31 +0000

Old Man Crowder, since drag is not linear but exponential, the savings will vary according to speed. For two vehicles of the same weight and power, the vehicle with lower CD when compared to the higher CD vehicle will increase the savings the faster the two vehicles go. In other words, at slow speeds it may be only 2-3% while at much faster speeds it may be 10-15%. Very few cars have CDs lower than .30. Compare this to the original Honda Insight’s .24 and the second and third generation Prius’ .26 and .25. Although I think the new Honda Insight’s CD will be in the .25 ball park, the next closest CD that I can find is .283 for the Corvette coupe. I also believe some of the other new hybrids out soon will also come under the .30 CD mark.

By: Anonymous

Anonymous — Thu, 12 Mar 2009 15:02:47 +0000

Several factors influence fuel consumption. The frontal area of the vehicle requires pushing the air aside. And then speed plays a role, the faster you go, the more force it takes to push that air out of the way. So below about 30 MPH drag plays a smaller role in fuel consumption, but as speed is increased, at some point it becomes the largest contributor to fuel consumption. A really slick car, like the Prius gets some of its 50 MPG due to its low drag.

By: Douglas Hvistendahl

Douglas Hvistendahl — Thu, 12 Mar 2009 15:01:26 +0000

Aerodynamics - depends on how fast you are moving. Not much in cities, quite a bit on the highways.

Take a look at the flow-aire design (search on "zero pollution motors" and follow up the links. Lightweight, uses triple compression & expansion instead of batteries. This PHAV has about the same performance as a PHEV, but the initial cost is roughly half as much. Efficiency is a bit lower.

By: Old Man Crowder

Old Man Crowder — Thu, 12 Mar 2009 13:35:16 +0000

Re: lighter materials — I agree that lighter is better as long as we’re not sacrificing safety. Carbon fibre is often suggested, but producing it requires vast amounts of energy and it cannot be recycled. We’d be trading one set of environmental problems for another.

Re: aerodynamics — How much does this really have on fuel consumption? Are we talking 10-15% or more or something like 2-3%?

By: Ross Nicholson

Ross Nicholson — Thu, 12 Mar 2009 05:00:37 +0000

All of these automobiles are at least twice as heavy as they need to be and none of them are anywhere close to being as aerodynamic as they need to be to carry America into the future. Open wheel wells ruin all of them, every last one, and none are boat-tailed, and most will lack aerodynamic belly pans.

Aerodynamics is a science. Such things as wheel diameter and width have optimums scientifically and economically. "Customer preference" and automotive industry pandering of styling fads cannot be allowed to endanger America's energy future any longer. We mandate miles per gallon (mpg), let Congress mandate maximum coefficients of drag (cd), so all manufacturers can work together on the same page for the benefit of society.