I’ve noticed an interesting tidbit: use the Vue’s automatic climate control and the engine does not shut down when coming to a stop. Kind of defeats the purpose of the hybrid system or the climate control, which ever you decide is more important.
All the writer needed to do here was read his owners manual...
About all that was required was to press the Hybrid A/C button (the "other" snowflake button with the green hybrid "H" next to it) Since the A/C compressor is belt driven on the GM BAS hybrids it obviously cannot operate when the engine is in Auto-Stop. Selecting the Normal A/C snowflake button therefore overrides the Auto-Stop function and essentially nullifies any fuel economy improvement or reduced emissions benefit.
Even though the A/C compressor quits pumping refrigerant when the engine stops in "hybrid" AC mode, the HVAC sytem will continue to deliver cooler air for up to a minute or so- long enough for most red-light events or typical stop & go traffic cycles. While some newer high voltage hybrids get around this issue by using an electrically operated A/C compressor, many older hybrids (eg. 01-03 Prius) and even some current production so-called FULL hybrids (i.e. Ford Escape HEV) still don't- and therefore function in a similar fashion to this Saturn Greenline. (i.e. the engine operates at all times unless A/C is commanded OFF or the "green" A/C mode is selected by the operator)
As far as I'm concerned, any sort of quantative analysis of fuel economy benefit (to whatever level of science) of this hybrid review could certainly be nullified if the writer spent the entire week using "regular" A/C functions as the primary hybrid function of Auto Stop-Start is paramount to any observed FE gains. This is especially true of the BAS/FAS hybrids which lack the ability to launch under full electric power and therefore rely mostly on this feature, hence thier GM classification as "mild" hybrids.
Thus a comment like...
Unlike other hybrid systems that are able to run on battery power at low speeds, the BAS system always requires the engine to be running.
is hardly an "apples to apples" comparison.What you conveniently forget to mention is the BAS technology contributes less than $2000 to the cost of the vehicle, therefore delivering returns on that investment much sooner than any other hybrid. If you desire to save even more fuel and pollute even less (and spend much more $$ to do so) a 2-mode version of the VUE Greenline with full electric launch AND advanced power source "blending" (via an automatic shift from an input split to a compound split configuration) will be available later this year and a "plug-in" capable version coming in 2009.
This writer goes on to state:
Onto the BAS hybrid system incorporated into the Vue. To say that I am not extremely impressed so far would be an understatement. Yes, the specifications say the Vue hybrid is able to achieve an average of 25 per cent better fuel economy than the standard Vue, although I’m not sure how this would actually translate to during my daily commute.
Since the parameters of this commute are not specified by the writer, what seems to be implied here is his daily commute must obviously include long periods of highway, freeway, or steady state driving, with few stops- which also negates most benefits of this hybrid's capabilities. In these conditions the 2.4L Ecotec engine would be performing (and consuming) in a fashion similar to a non-hybrid FWD VUE, with the exception of small portions of electrical assist while under higher engine demand loads due to heavy payloads, mountainous terrain, or when demanding WOT acceleration or passing power .
FYI-The 25% improvement mentioned in some Saturn literature is based on the new "real world" 2008 EPA COMBINED fuel economy test results which lists the non-hybrid FWD 2.4L VUE as 22mpg and the Greenline model achieving 28mpg (again, COMBINED highway & city in US gallons) Early owner responses to the EPA site fueleconomy dot gov appear to corroborate these numbers. Not sure what this writer's FE numbers were,since he failed to publish them in order to support his negative comments.
Since there's no way for ANY hybrid to compensate for poor driving habits, certain environmental conditions OR a serious lack of product knowledge, in this case one could certainly state... "Your mileage my vary!"
JMO
WopOnTour
