So close and yet so hot

[Saguaro]

It's just the way I roll; it's the game I play.
[/quote]

I'm with you Tony. I've been driving without A/C here in Phoenix, Arizona the last month and I've been able to keep my mileage signifigantly higher (59.0 MPG). In fact, my last fill-up was July 2nd, over a month ago. I have never gone that long between fillups before. I'm going for my first 60 MPG tank so I can't blow it now by turning on the A/C! It helps when the outside temperature is 90 degrees at 8:00 am at startup - I get to stealth mode real quick.

My wife thinks I'm crazy for driving with the windows down (especially when it's 115 in the afternoon) but I don't care! I'm still trying to figure the car out and see what it's capable of. Phoenix is actually pretty ideal for the Prius - relatively flat terrain, mild temperatures (most of the year).

I love my Prius!

[TonyPSchaefer]

Wow, Hobbit. I had that exact thought on my way home tonight. Mainly because of this thread and the discussion of battery heat. I was wondering why the battery vent is in the cabin whereas in the classic it's on the outside. Right? I mean, I assume that's what the vent on the side of the classic is for.

The actual thought I had was to connect a shop-vac hose from the far-right dash vent straight back to the battery vent. But that's a little too extreme for me. Let me know how it works out for you though.

When wanting to cool the pack, would it be prudent to roll the back passenger window down all the way to get the most air possible into that vent?

[inside reference: you've inspired me to make my own wooden gazebo reinforcements. I'll test them next weekend]

[paulccullen]

<div class='quotetop'>QUOTE(paulccullen @ Aug 3 2007, 07:58 AM) [snapback]489916[/snapback]</div>

OK, I admit, I play that "how high can I get the MPH" game too[/b]

Um. TYPO. I meant MPG.

I'm wondering if "hypermilers" are annoying other drivers and giving the Prius a bad image as a slow pokey car. In order to get 60+MPG you'd have to be moving and accelerating *really* slowly. Fortunately Al Gore III may have counteracted that image a little.

I drive at the ambient traffic speed (and use the A/C when it's warm), and manage to get *only* 50-51MPG (less in winter)

But Tony's comparison to arcade games is a good one. We all get a little obsessive/compulsive over things...

[usbseawolf2000]

I experienced the same behavior last Thurs trip back home. It was 95 deg outside (according to MFD) and I couldn't glide. This was after 25 miles drive. I had the same thought as Tony so I turned the AC on and pointed the passenger side vent upward to the roof. After a few minutes, I was able to glide. When I got home, MPG for that 44 miles commute was 66.6 MPG. It was a record for me.

[hobbit]

..."you'd have to be moving and accelerating really slowly"
Completely incorrect. One in fact wants to be reasonably brisk on
the acceleration side to run the engine efficiently. What might be
a little different is the optimal *timing* of when you do it, i.e.
leaving more of a gap ahead before deciding to do your "burn". This
may give the impression of "pokey" to people who just don't understand,
but quite normal acceleration with the right timing and duration
still yields satisfyingly high MPG. Deceleration is also when the
significant gains happen if one does so smoothly and from reasonably
far out, to maximize regenerative recovery -- which given how far
too many people have conditioned themselves to drive, may also be
thought of as "pokey" but loses absolutely nothing in terms of time
spent at a red light.
.
But steady-state speeds are entirely normal and on par with everyone
else around, except perhaps on freeways where a nominal travel rate
of 60-65 yields good MPG performance and the clowns doing 85 might
view that as "slow". But it's certainly not just hybrids doing that;
consider trucks, RVs, rattletrap farmer pickups, and people who want
to avoid that v^3-proportional MPG hit. So don't call it "pokey" in
a blanket fashion until you really understand what's going on.
.
_H*

[bwilson4web]

<div class='quotetop'>QUOTE(hobbit @ Aug 3 2007, 09:36 PM) [snapback]490307[/snapback]</div>

. . .
I've been thinking how absolutely stupid it is that the interior of
the car picks up so much heat, while the engine block tends to stay
fairly cool even on a hot day. We want the exact *opposite*, and it
would be lovely if there was a way to pick up all that cabin heat
before it becomes cabin heat and send it all to the engine coolant.
Year-round EBH users wouldn't need to plug it in on hot days.
Unfortunately, it would involve a fairly complex pickup structure,
or maybe some sort of black rubber mat with water channels you'd
throw over the whole car and hook into the cooling system somehow..
.
[/b]

I've been thinking along the same lines and how a foam and fiberglass hood and trunk lid might accomplish this goal. It would be easy enough to make a foam and glass fiber mold and then build up a composite structure.

My thinking is a clear, thermal plastic could be vacuum formed over the mold for the outer surface. Then a layer of pipes/channels built up followed by a carbon fiber and foam structure to mechanically hold the assembly. Making it look pretty would be a challenge but it should capture a lot of solar heat.

Bob Wilson

[MaxLegroom]

<div class='quotetop'>QUOTE(paulccullen @ Aug 4 2007, 11:35 AM) [snapback]490510[/snapback]</div>

Um. TYPO. I meant MPG.

I'm wondering if "hypermilers" are annoying other drivers and giving the Prius a bad image as a slow pokey car. In order to get 60+MPG you'd have to be moving and accelerating *really* slowly. Fortunately Al Gore III may have counteracted that image a little.

I drive at the ambient traffic speed (and use the A/C when it's warm), and manage to get *only* 50-51MPG (less in winter)

But Tony's comparison to arcade games is a good one. We all get a little obsessive/compulsive over things...
[/b]

Some hypermilers may indeed be annoying to other drivers. Right now, I've an average of 61mpg on the current tank. I didn't get it by moving really slowly, but a lot of my driving was in Sandbridge in Virginia Beach, and I seemed to be moving between recharging and EV a lot. Thing is, I didn't lose much of the average I had there driving across Norfolk, Portsmouth and Suffolk. Actually, at the end, someone in a Neon coupe wanted to show his buddies how fast he was by burning the 35th St. offramp, only to find himself stopped at the next light, which is where I caught up to him. When he blasted off from the light, I glued the Prius to his rear bumper, kept with him through the next corner, and pulled next to him at the next stop sign. He (and his buddies) slinked off to the left, and as I glided into my parking space, the MFD read an average of 61.0mpg. While the last is actually unusual for me with the Prius, once in a while, an opportunity too good to pass up shows itself. A more usual style is for me to drop back a bit. Between gliding up to lights and keeping an eye open I usually am passing other traffic in the city.

I use the A/C all the time. Just because I came back from Kuwait six months ago doesn't mean I like the heat, and my Prius is black.

Tony is spot on with the arcade analogy. It is like playing a video game. The Prius even steers like one, especially compared with my old Sebring, which had steering that talked more than a Hollywood insider.

[jdenenberg]

<div class='quotetop'>QUOTE(Danny Hamilton @ Aug 3 2007, 11:16 AM) [snapback]489921[/snapback]</div>

Ok, so:

Some people have moved some of their acceleration off of gasoline and on to "the grid" (Plug-In Prius)
Some people have moved some of their ICE warm up off of gasoline and on to "the grid" (EBH)

In both instances people are finding that "the grid" is a more efficient and cheaper source for the energy.
[/b]

Danny,

The Grid may be cheaper, but it is not more efficient. The typical efficiency of electric power is about 25% from the fuel to the home. Then you have to take into account the efficiency of the using appliance.

There are two reasons for the price differential. First is that the utility has the benefit of "economy of scale". The second is that you are sidestepping "road use" taxes (may be a temporary situation).

Just keep these factors in mind when considering the use of generated electricity to replace direct use of gasoline/diesel fuel in transportation.

Jeffd

[Danny Hamilton]

<div class='quotetop'>QUOTE(jdenenberg @ Aug 8 2007, 09:47 AM) [snapback]492371[/snapback]</div>

The Grid may be cheaper, but it is not more efficient.
[/b]

I haven't seen any studies yet. How efficient is the Prius from fuel to battery?

There is also the matter of what is meant by efficiency.

As one example, although it would be a bit redundant in my original comment, efficient might mean "most efficient use of my money", in which case use of the grid is a more efficient "pocketbook to battery" path than use of gasoline.

[JackDodge]

<div class='quotetop'>QUOTE(TonyPSchaefer @ Aug 3 2007, 08:40 PM) [snapback]490237[/snapback]</div>

No prob.

Does anyone know the UV rating on the windows?
Sounds odd, I know, but since I work due South of where I live, the sun is ALWAYS to my left in the morning and ALWAYS to my left when I'm coming home. And to make matters worse, it's almost ALWAYS in that gap between the visor and the door jam.

I have been working under the impression that there's at least some level of UV protection in the window. No facts, just optimistic hoping. Even when I row down the windows, I normally don't put down the driver's window because - if you've met me you know - I'm extremely white and burn easily. During the course of a one-hour drive, five times a week (10 hours of sun time total per week), I'm sure that I would either sunburn or at least have an oddly dark left side of my face.
[/b]

There is some UV protection, sure, but not enough for my preferences. I have the sun on my side of the car going to the office and on the way home so I got tinting and it seems to make a significant difference. They keep the office building at 65 during the summer so when I get in the car to go home, I just luxuriate in the heat for the first ten minutes and then turn on the A/C. I've not had the heat problem that you describe so perhaps the tinting helps? Thanks for the insight though, I'll remember that if I ever get a strange issue with MPG when it's hot outside.