What design change would you make for 100 MPG

<div class='quotetop'>QUOTE(John in LB @ Mar 24 2007, 01:01 PM) [snapback]411516[/snapback]</div>

You can already achieve 100 MPG at speeds between 15-25 mph. What is the target speed(s)?

As for technical changes, here is my short list of Prius mods:

• exhaust energy capture - ammonia absorbsion AC, exhaust to cabin heat-pipe, turbo alternator
• pressurized wheel bearing lubrication
• dry-sump transaxle - all gears and cooling are pump lubricated and cooled
• all pumps including ICE coolant, electrically, demand operated
• fully enclosed and baffled ICE and underbody
• low-drag radiator coolant loop built into hood
• descending front air-dam and side skirts at speeds above 50 mph
• replace all rear view mirrors with cameras
• incorporate antennas in front and rear window glass
• thermoplastic-fiberglass bodies
• driver and passenger, fully articulating, electric seats
• 70+ psi tires on carbon fiber, enclosed wheels, with active, inertial suspension
• smart cruise control
• recessed windshield wipers
• Rain-X dispensor

Bob Wilson

 

I am not a technician but have been following the news and trying to read between the lines.

I predict that Toyota will produce a car, perhaps the next generation Prius which will achieve 100 mpg and they will do do it by increasing the battery size, maybe to three times what it is now. There will be other refinements, but they will not be earthshaking. The car will have an EV switch and maybe five miles range in EV mode. The battery will have the same warranty which we get now.

It will achieve this by increased electrical assist. It will be as close to a Plug in Hybrid as can be done with the present battery technology and still meet the demands of the marketplace. It will meet all of the criteria which were set forth above.

 

I don't think it would be worth 100mpg in typical driving, but I think that a lean burn engine a la 5MT Honda Insights and Civic Hybrids would make for some pretty substantial gains on the open road. The one caveat is that I would not want it if they could not find a way to eliminate the extra NOx emissions. Direct injection capable of a stratified charge might do the trick, or perhaps a clever exhaust treatment. If an Insight w/ lean burn can do 80mph at 55mph a Prius would probably be worth 65mpg, plus or minus due to the added weight and aero drag.

I think a more efficient battery or perhaps an ultracapacitor for electrical energy storage would be worth a solid mileage boost around town.

I hesitate to suggest the use of advanced composites to lighten the car, though that would work well. Problem is that you can't recycle carbon fiber, so I'm not a huge fan. Aluminum, also a la Insight, might be the right kind of compromise.

 

What if you use a small diesel that turns a generator to produce electricity to run the car and the electric motors. A diesel can be very efficient under load at a constant rpm. You could even keep the batteries and allow the engine to shut off when not needed. I am not sure that would yield the 100mpg you ask for but it would probably get very close.

 

<div class='quotetop'>QUOTE(John in LB @ Mar 24 2007, 01:47 PM) [snapback]411543[/snapback]</div>

I wasn't clear. The 100 MPG was going to be via what speed or driving profile? New EPA? Old EPA? One of the European or Japanese standards? City? Highway? Combined? Understanding the driving profile for the 100 MPG dictates the relative merits of each change.

The other, missing question, is the cost of each change. For me, this is the more interesting problem because it leads to "What can an individual do to retrofit one of these systems to their vehicle?"

Bob Wilson

 

Heck, this is easy.

If I have $100k to work with, I'll give you 300 miles of range, astonishing acceleration, and at least 150mpg (of gas equivalent). Would have everything that the Prius has, as we'd just use that glider to start with (well, in reality, the Prius isn't a great glider for this, but we'll pretend for now) And the first prototype could be built in about a month.

I don't suppose what I'm going to say will surprise anybody: Remove the internal combustion engine. Stuff the thing full of Li-Ions (go buy a pack from Tesla to make this part easy) and put an AC Propusion drivetrain in there. Presto. Done. All goals met.

If produced in the quantities of the current Prius, they could sell (educated guess) for about $60k to begin with. And I'll be first in line.

This is not rocket science. This isn't anything that hasn't already been done. As soon as we talk about "improving gas mileage" we're hobbling ourselves to think in terms of having to burn liquid fuel.

OK.... so what did I win?

 

I think you are using old data as far as weight loads. look around the average person no longer weighs 150 pounds better raise it to 200 pounds per. so a load capacity of 800 pounds is more likely plus actual cargo.

as to improvement I would like to see a wind operated generator that would be used while driving with a low resistance motor bearing assembly to recharge the traction batts.




I have an electric vw fox and have experimented with "spinners" hup caps that spin.
I wound a copper coil around them and a magnet mounted on the rim and wired those small neon under car lights up, and at night I power the lights with my spinners themselves. So I know a wind generator could work if designed better than my style of a coil and magnet can work to create juice to operate those small lights.

 

What I would like to see is programmable cruise control to have the computer handle pulse and gliding (I didn't search to see if someone suggested this before, if so, not trying to steal anyones ideas):

Have an entry screen on the MFD with simple commands like:
P 55, 25 (pulse to 55 at 25 mpg)
G 45 (glide to 45)
R (repeat)

Then the computer would know when to spin the ice instead of having to be permanently spinning it above 40, so you could no arrow glide at high mpg or just sit back on an open road in P&G CC mode to take full advantage of the car's abilities. Also, there wouldn't be that brief regen moment that is hard to bypass when going from pulse to glide.

 

Paint the 'sky-facing' body with solar-electric paint and enable car to travel faster on battery only, when charge is sufficient. Is there, perhaps, a way to translate the air flow from normal travel into energy? Guys, remember when you were kids and had those toy cars which got their energy from contacts on the track?

 

I would require that all the passengers of my new car go on a diet and get themselves into a nice healty weight range before riding in it.

The rest of my ideas, and the $25 millon X prize I'll keep for myself.

 

<div class='quotetop'>QUOTE(John in LB @ Mar 24 2007, 01:01 PM) [snapback]411516[/snapback]</div>

Downsize the brakes and fit rear motor-generator(s). A friction brake is an admission of failure.
Use more aluminium or carbon fibre in the suspension, transmission and body.

 

A computer controlled driving system. A central computer timed so that nobody ever has to stop or slow down more than would be optimally efficient. Not a new idea, and probably not cost effective to implement... yet!

Look for other energy losses than aerodynamics. Road friction, static charge, tire compression. If there's a way to recover some of that energy without increasing weight/drag that could help.

A lightning rod to collect ambient static charge...

MarinJohn's idea of a perpetual motion machine would be good too. Make that work, and you'll do well for yourself