Posted by Bob Wilson on February 1, 2007, 2:16 pm
> There is/was something about the EPA city tests that the Prius was able
> to take advantage of, that human drivers can not. Is a gross mistake to
> extrapolate the Prius EPA ratings to all other vehicles.
The original EPA test involved:
1) many stops
2) average speed less than 30 mph in city
3) average highway speed ~48 mph
This is the driving profile of 40 years ago in rural, small towns not
served by interstates. These small towns had nearly universal speed
limits of 25 mph and at the city limits, two-lane, 55-60 mph roads. But
over time, population shifts, traffic management and road improvements
changed how we drive.
The hybrid drive excels at in the original scenario. The specific
savings are: (1) auto-stop when coming to a stop, and (2) automatic
switching between ICE and EV power. To achieve simular results, I
modified my commute route to maximize driving in simular to EPA profiles
and it has become easy to replicate the EPA results.
Bob Wilson
Posted by Bill on February 3, 2007, 7:57 pm
>> There is/was something about the EPA city tests that the Prius was able
>> to take advantage of, that human drivers can not. Is a gross mistake to
>> extrapolate the Prius EPA ratings to all other vehicles.
> The original EPA test involved:
> 1) many stops
> 2) average speed less than 30 mph in city
> 3) average highway speed ~48 mph
> This is the driving profile of 40 years ago in rural, small towns not
> served by interstates. These small towns had nearly universal speed
> limits of 25 mph and at the city limits, two-lane, 55-60 mph roads. But
> over time, population shifts, traffic management and road improvements
> changed how we drive.
> The hybrid drive excels at in the original scenario. The specific
> savings are: (1) auto-stop when coming to a stop, and (2) automatic
> switching between ICE and EV power. To achieve simular results, I
> modified my commute route to maximize driving in simular to EPA profiles
> and it has become easy to replicate the EPA results.
> Bob Wilson
In some respect yes, in other respects no. In summer I can meet the highway
figure for any trip longer than 30 miles by driving 55 mph (wind
not-with-standing) but on shorter trips I can't overcome the warm-up penalty
that quickly. I can meet the city figure only after I get out of the
warm-up penalty box and, unfortunately, my commutes to town (3 miles at 55
mph) doesn't get me back on the ice. In the winter, I can't meet either
figure, but I only lose about 10%.
Posted by Bob Wilson on February 4, 2007, 2:41 am
> > The original EPA test involved:
> >
> > 1) many stops
> > 2) average speed less than 30 mph in city
> > 3) average highway speed ~48 mph
> >
> > This is the driving profile of 40 years ago in rural, small towns not
> > served by interstates. These small towns had nearly universal speed
> > limits of 25 mph and at the city limits, two-lane, 55-60 mph roads. But
> > over time, population shifts, traffic management and road improvements
> > changed how we drive.
> >
> > The hybrid drive excels at in the original scenario. The specific
> > savings are: (1) auto-stop when coming to a stop, and (2) automatic
> > switching between ICE and EV power. To achieve simular results, I
> > modified my commute route to maximize driving in simular to EPA profiles
> > and it has become easy to replicate the EPA results.
> >
. . .
>
> In some respect yes, in other respects no. In summer I can meet the highway
> figure for any trip longer than 30 miles by driving 55 mph (wind
> not-with-standing) but on shorter trips I can't overcome the warm-up penalty
> that quickly. I can meet the city figure only after I get out of the
> warm-up penalty box and, unfortunately, my commutes to town (3 miles at 55
> mph) doesn't get me back on the ice. In the winter, I can't meet either
> figure, but I only lose about 10%.
What year or model?
Some of us are working on the problem for the 2001-2003 models:
http://hiwaay.net/~bzwilson/prius/pri_temp.html
Sorry about the poor English. Some was quoted from friends overseas and
I haven't take a lot of time to edit everything down due to other time
constraints.
Bob Wilson
Posted by Bill on February 4, 2007, 2:47 am
>> > The original EPA test involved:
>> >
>> > 1) many stops
>> > 2) average speed less than 30 mph in city
>> > 3) average highway speed ~48 mph
>> >
>> > This is the driving profile of 40 years ago in rural, small towns not
>> > served by interstates. These small towns had nearly universal speed
>> > limits of 25 mph and at the city limits, two-lane, 55-60 mph roads. But
>> > over time, population shifts, traffic management and road improvements
>> > changed how we drive.
>> >
>> > The hybrid drive excels at in the original scenario. The specific
>> > savings are: (1) auto-stop when coming to a stop, and (2) automatic
>> > switching between ICE and EV power. To achieve simular results, I
>> > modified my commute route to maximize driving in simular to EPA
>> > profiles
>> > and it has become easy to replicate the EPA results.
>> >
> . . .
>>
>> In some respect yes, in other respects no. In summer I can meet the
>> highway
>> figure for any trip longer than 30 miles by driving 55 mph (wind
>> not-with-standing) but on shorter trips I can't overcome the warm-up
>> penalty
>> that quickly. I can meet the city figure only after I get out of the
>> warm-up penalty box and, unfortunately, my commutes to town (3 miles at
>> 55
>> mph) doesn't get me back on the ice. In the winter, I can't meet either
>> figure, but I only lose about 10%.
> What year or model?
2005 L6
> Some of us are working on the problem for the 2001-2003 models:
> http://hiwaay.net/~bzwilson/prius/pri_temp.html
> Sorry about the poor English. Some was quoted from friends overseas and
> I haven't take a lot of time to edit everything down due to other time
> constraints.
> Bob Wilson
Posted by on January 4, 2007, 7:50 pm
> EPA Lowers Prius Mileage Estimate
> Feds' Findings Confirm Consumer Complaints
> By Joe Benton
> ConsumerAffairs.Com
> December 19, 2006
> Prius owners concerned about poor mileage in their hybrids have been
> belittled, ridiculed and misled as they searched for some reason why
> their little cars continually came up short in fuel mileage.
> Prius consumers have listened while dealers and technicians offered
> sometimes outlandish explanations of why their own fuel mileage
> calculations were wrong and why Toyota claims for the Prius were
> correct.
> Other Prius owners even accused the complainers of disloyalty to the
> hybrid movement.
> Toyota claimed the little hybrid would get 60 miles per gallon in city
> traffic, not just the 45 many consumers were experiencing.
> One Prius owner told ConsumerAffairs.Com that her Toyota technician
> went so far as to explain how the onboard computer in the Prius took
> into account of head winds along with other sophisticated
> calculations.
> Now it turns out that most of the hybrid owners questioning Toyota's
> mileage claims for the Prius were right on target while Toyota was
> wrong, at least according to the Environmental Protection Agency's new
> mileage estimates.
> The facts seem to be that the Prius gets 45 miles to a gallon on
> average in the city. That is the new word according to the EPA.
> The government fuel economy estimate also confirms
> ConsumerAffairs.Com's road test of the Prius in July. That test drive
> concluded that the Prius got 45.2 miles per gallon in vigorous city
> driving.
> Just this last October, the very same EPA that now says the Prius gets
> roughly 45 miles to a gallon praised the little car for topping the
> government mileage list with 60 miles per gallon in the city and 51
> miles per gallon on the highway despite protests from many Prius
> owners saying that just wasn't so.
> The Prius did not come close to 60 miles per gallon in the
> ConsumerAffairs.Com test either.
> So now the troubling question for Toyota is this: Will the Prius with
> its new and more reliable mileage rating still be a hit with
> consumers? Will the little car that is now rated at 45 miles per
> gallon in the city be as popular as the same car that was believed to
> get 60 miles per gallon around town?
> A Toyota spokeswoman said her company expects customers to understand
> that the technology in the Prius hasn't changed, and company marketing
> for the popular hybrid will not be revised.
> The desire for fuel economy is the reason most consumers plunk down
> big bucks for a Prius or one of the other gas-electric hybrids that
> are consuming a fast-growing slice of the American auto market.
> Now that the EPA has washed most of the fiction from its fuel mileage
> numbers, will the hybrid market suffer?
> http://www.consumeraffairs.com/news04/2006/12/priius_epa.html
Can't do much about spilled milk, so I would think a lot of future Prius
buyers will be pleasantly surprised how much more they get than the EPA
sticker. Unfortunately, buyers of traditional cars won't be so lucky.
Here in Agawam MA one can get a ticket for letting their car idle for 5
minutes or more. I suppose something like this would be hard to enforce but
the gist of it brings to everyone's attention how wasteful it is to do
otherwise. I think the Prius is exempt from this ruling ;)
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> to take advantage of, that human drivers can not. Is a gross mistake to
> extrapolate the Prius EPA ratings to all other vehicles.