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I was thinking about ev from a stoplight and I realized maybe honda is right in not doing EV at that point. The engine might be more efficent to start the car moving that the motor because of the losses in converting to electrical and back to mechanical.

At first glance it appears that using zero gas to get you moving is better than using gas, but maybe over a longer term when the battery needs to regen you are taking a larger hit in mileage. Maybe this larger hit is not noticed because it happens over a longer period.

The HCH II is now just .7 away from the prius and though it may take a small hit in the peak of summer, I think fall will bring the numbers even closer.

Hi Tom:

___Honda unfortunately does not have it right as can be seen in the horrid bumper to bumper traffic numbers achieved by the HCH-I and II in CR’s city test cycle :( Honda has found a relatively inexpensive way to create a hybrid but not without sacrifices … EV mode at the slowest speeds in particular is why an EV is so efficient to begin with. The thermal efficiency of battery to wheels (chemical to mechanical) during acceleration under EV is upwards of 90 + % vs. a standard SI or CI-ICE in the mid 20’s during initial acceleration at an absolute best! During initial light off, the ICE thermal efficiencies are absolutely abysmal with most in the high teens for total chemical (gasoline) to mechanical conversion. Even though a hard Mechanical to EV conversion (braking regen) is only in the 30’s (all of this is off the top of my head so do not quote me), it is the slow and steady charge from an ICE running above 30% efficiency that makes the numbers work out. An electric motor at 0 to low RPM’s puts out an ungodly amount of torque (max at 0 RPM) and the efficiency is so high up the scale as to make acceleration using the ICE extremely painful by comparison.

___A counterpoint to this … An ICE in a FAS is completely out of the equation whereas an electric motor is usually never disconnected as is the case with the Prius I/II with THS/HSD. You can feel a slight drag in Prius II during a Glide whereas in a FAS no matter the vehicle, your distance is truly based upon tire RR, mechanical friction of the various rotating parts still spinning, and aero drag alone.

___When long range OEM EV’s and/or OEM PHEV’s arrive for the consumer to purchase off the showroom floor, you are going to wonder why Honda took the single MGSet path as well as making extensive use of it even today? That second MGSet is what makes the Prius II perform how it can and until Honda either clutches IMA or adds a second MGSet for a pure EV mode along with Regen and ICE starts, they will always be looking at the Prius II’s results from behind the eight ball. The Prius II is not only larger and heavier automobile; it really does achieve 60 mpg in the FTP75, which the HCH-I/II will never achieve in their present design. The Prius II’s ICE is running < 50% of the time during the FTP75 whereas the HCH-I/II are running for far longer period of the total test :( I am talking a strict adherence to the FTP75 test protocol’s, not what you, I, and any number of hypermiler’s do in the real world ;)

___Good Luck

___Wayne

I'm doing my best to narrow that gap :D 59.7 on my last tank and this tank (it will be a while before my next refill) should be a similar number.

yeah if i had to pick between the civic II or the prius II then i'd probaby get the civic, i mean really in the very end its about the mileage and not how complex the system is. But prius II for sure has an advantage of bumper to bumper traffic, when it comes to which car is easier to get through the day with.

Although many have proven otherwise.

I don't have EV at all. Having even a modest EV in bumper-to-bumper traffic would be wonderful to avoid an FE drop.

Otherwise, I'll accept the reports that EV has it's limits.

The great thing about hybrids is it recovers kinetic energy that would otherwise be 100% wasted. Still, the Laws of thermodynamics state you will never recover 100% of that energy. It leads me be conclude that the best hypermiling involves good use of the ICE first, the Assist second.

It leads me be conclude that the best hypermiling involves good use of the ICE first, the Assist second.

Exactly.

i like the idea of cvt letting your engine be at the most efficent rpm, while messing with ratios/assist.

ICE is great just never starting out.

Even when letting the ICE/generator completely recharge the battery, with no regen, the FEH can get >40mpg diving EV. This is 4mpg higher than EPA City and can be had right from the showroom floor before break-in and driver experience. The problem with most FEH drivers is, they believe EV is a wash because they think the ICE will burn more fuel to recharge. This is not only false, but add regen and some thinking, and the FEH can double EPA on short trips using EV.

Improve the battery technology, and we'll see even better FE in Full Hybrids. IMO, Toyota dropped the ball by only offering a V6 first in the Highlander and 400H Hybrids. The market wants FE in SUV's because they can get power all they want from any of the other manufacturers.

GaryG

It leads me be conclude that the best hypermiling involves good use of the ICE first, the Assist second.

True if your have the patience to use hypermiling techniques. But for the average Joe who doesn't know didly about how to drive efficiently, the Prius appears to be more forgiving.