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Super Efficient Cars [very large pictures]
http://www.silentpcreview.com/forums/viewtopic.php?f=18&t=46218
Page 4 of 13

Author:  NeilBlanchard [ Tue Jul 08, 2008 1:10 am ]
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Hello,

I see that the Think Ox weighs 1500kg (3300lbs) -- which is very heavy. Too heavy if you ask me...

Author:  klankymen [ Fri Jul 18, 2008 3:12 pm ]
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Hey Neil and Others,

Do you know how fast the Gasoline Generator in the Aptera Typ-1 Everywhere can charge the Batteries? I'm somewhat concerned by the fact that the driving motor has 30kW, but the charging one only generates 10kW... I wonder if it can keep up, or if you have to make little stops along the way to allow for the charger to work.

What else... I'm a bit concerned how a single wheel, RWD car would perform in the snow... sure it's great in california (and would be nice here too, if only we could see some effects of global warming), but I don't know how pleasurable it would be on snowy days.

Let's see, apart from that....
I WANT AN APTERA!!

It's completely revolutionary looking (in a good way, I think), and it's cheap, roomy (for 2 people), and uses one quarter the gasoline of my current car. (I don't even care about the environment when I say that, just my wallet :wink: )

Author:  NeilBlanchard [ Fri Jul 18, 2008 6:55 pm ]
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Hello,

AFAIK, it can keep "ahead" of the electric motor. You can find out more at the Aptera Forum:

http://apteraforum.com/index.php

Author:  aristide1 [ Sat Jul 19, 2008 1:41 pm ]
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http://www.msnbc.msn.com/id/25749580/

Hey what ever happened to the Mobil Economy Run? Was it crushed by stockholders or Dick Cheney?

Author:  AZBrandon [ Sat Jul 19, 2008 9:32 pm ]
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klankymen wrote:
Do you know how fast the Gasoline Generator in the Aptera Typ-1 Everywhere can charge the Batteries? I'm somewhat concerned by the fact that the driving motor has 30kW, but the charging one only generates 10kW... I wonder if it can keep up, or if you have to make little stops along the way to allow for the charger to work.


They're only vaguely related. Just because a Corvette has 400 horsepower doesn't mean you are putting out 400 horsepower when idling or when cruising in 6th gear at 1400rpm on the highway. In fact I know for a fact you're not, it should only take 25 to 50 horsepower for most cars to cruise at reasonable speeds on the highway.

All that extra power is only used when you're accellerating at maximum rate. The Aptera's got a 30kw motor for accelleration up to speed, but only needs the 10kw generator because you use far less power to hold speed than to accellerate.

Author:  klankymen [ Sun Jul 20, 2008 1:51 pm ]
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AZBrandon wrote:
klankymen wrote:
Do you know how fast the Gasoline Generator in the Aptera Typ-1 Everywhere can charge the Batteries? I'm somewhat concerned by the fact that the driving motor has 30kW, but the charging one only generates 10kW... I wonder if it can keep up, or if you have to make little stops along the way to allow for the charger to work.


They're only vaguely related. Just because a Corvette has 400 horsepower doesn't mean you are putting out 400 horsepower when idling or when cruising in 6th gear at 1400rpm on the highway. In fact I know for a fact you're not, it should only take 25 to 50 horsepower for most cars to cruise at reasonable speeds on the highway.

All that extra power is only used when you're accellerating at maximum rate. The Aptera's got a 30kw motor for accelleration up to speed, but only needs the 10kw generator because you use far less power to hold speed than to accellerate.


Thanks.

I knew that you don't always use everything (the Bugatti has a needle telling how many HP you are using at the moment instead of a rev counter), but I wasn't sure how much exactly you would use. I can easily imagine cruising along on a highway at 40hp or so, but at 12? Even for such an aerodynamic car, that's not a lot.

Big ups to the guys if they can do it is my thought.

Author:  sea2stars [ Tue Jul 29, 2008 2:34 pm ]
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Came across this last night, the NmG. About $30k? Hrm.

Author:  NeilBlanchard [ Tue Jul 29, 2008 2:56 pm ]
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Hi,

I seen that and it is not very good. It is the Corbin Sparrow, now built by someone else; and it is horrible compared to the Aptera Typ-1e.

Author:  sea2stars [ Tue Jul 29, 2008 4:47 pm ]
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Ah.. I knew I remembered it from somewhere. Yeah.. I had the same feeling. For the same amount, you'll be able to get something with far better range, research and usefulness.

Author:  Agent_N [ Tue Jul 29, 2008 4:48 pm ]
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klankymen wrote:
mr. poopyhead wrote:
20hp seems a LOT more sensible for moving a few people around, than the current standards...
20hp seems a lot more sensible if you want to wait 20 minutes turning into a busy street.


Have you ever looked up the difference between horsepower and torque? Your answer suggest you don't know a thing about either. A twenty horse diesel has plenty of get up and go because it is torque that launches you off the line. Horsepower on the other hand needs to be high if you want high RPM power. A dyno test will show you that horsepower comes on strong at higher RPM's whereas torque kicks in early at lower RPM's. If a diesel engine has 20 horse and 80-100 ft. lb. of torque, it will get you up to speed easily from a stop, just don't try to pass a semi at 65 mph because it will take awhile.

Author:  Agent_N [ Tue Jul 29, 2008 6:34 pm ]
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mattthemuppet wrote:
AFAIK the main problem with diesel hybrids (along with the additional weight of the often iron blocked engine) is that due to their high compression diesels are very hard to stop start, which is the main approach to petrol hybrids like the Prius. I think that diesels emit alot of particulates on start up, though I could be wrong and there are also particulate filters to deal with that.


Actually, diesels are much easier to start in that if they are warmed up they will fire on the first compression stroke after the starter engages. Not only that, but it is easier if the generator/starter is built in to the engine acting as a fly wheel much like the 24 or 48 volt systems that where being tested a couple of years ago. I think the Prius uses a similar system if memory serves me correctly.

Particulates are a problem when the engine is cold, but much less so if it is warm due to the block, head and air temperature being where they are supposed to be rather than being cold.

The engine weight is only a problem when accelerating or when climbing an incline. The high torque diesel engines produce pretty much negate the extra weight of the engine. VW's TDi Diesels are proof of that as they easily get 40+ highway MPG and perhaps even higher if you are easy on the accelerator.

Author:  NeilBlanchard [ Tue Jul 29, 2008 7:22 pm ]
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Hi,

Electric motors develop their maximum torque at 0 RPM -- so they start accelerating much faster than the HP rating would imply.

Author:  spookmineer [ Wed Jul 30, 2008 2:02 pm ]
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HP = torque * RPM * some constant

The constant is not important, but this means the power will increase if RPM goes up while torque stays constant.
If the torque curve is flat, the power curve will be a very steady climbing line.

In most cases, the power curve will reach it maximum at higher RPM than where the torque curve drops down. This is because the power will still increase because of the increasing RPM, when the torque curve falls down (RPM increase compensates for torque decrease for some time).

Author:  sea2stars [ Wed Jul 30, 2008 9:09 pm ]
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17 Electric Cars You Must Know About

Author:  NeilBlanchard [ Thu Jul 31, 2008 2:33 am ]
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Hi y'all,

They left out an important electric car: the Aptera Typ-1e.

Author:  aristide1 [ Sat Aug 02, 2008 10:49 am ]
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From http://www.aptera.com/details.php

Quote:
Diesel or Gasoline? Our first prototype, the Mk-0, was a parallel hybrid Diesel and achieved an average of 230 MPG at a steady state of 55 MPH. This was pure Diesel/mechanical drive with no electric assist. Diesel is attractive for its Carnot efficiency and the increased enthalpy of Diesel fuel vs gasoline. However, diesel contains lots of unburned hydrocarbons and NOX compounds, and it's impossible to get a small Diesel engine certified for emissions in California. Therefore, the typ-h uses a small, water-cooled EFI Gasoline engine with closed loop oxygen feedback and catalytic converter.


Why not propane, a cleaner fuel? What would the range for this vehicle be with a single 20 pound bottle? In the summer such bottles are everywhere because of gas grills, the same would happen all year long if such vehicles were on the road. No catalytic converter and all the other nonsense.

Interesting - the photo on the same page shows a Bridgestone RE-92 tire. Very low rolling resistance, worst rain tire I have ever owned. I would never buy this tire again, and if it came standard equipment I would have them removed immediatelty.

If I wanted to stick to extremes that made no sense I would think like someone else around here.

Author:  aristide1 [ Sat Aug 02, 2008 11:16 am ]
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spookmineer wrote:
HP = torque * RPM * some constant

The constant is not important, but this means the power will increase if RPM goes up while torque stays constant.
If the torque curve is flat, the power curve will be a very steady climbing line.

In most cases, the power curve will reach it maximum at higher RPM than where the torque curve drops down. This is because the power will still increase because of the increasing RPM, when the torque curve falls down (RPM increase compensates for torque decrease for some time).


For an ICE the speed range at which peak torque will be determined by several factors; cam timing, port design, etc. If one wants to create a gas engine stump puller that peaks at 2000 rpm they probably can. The diesel engine apparently has other reasons for not reaching high rpms, and I would guess reciprocating weight is an issue. Hot rodders of course see this only as an obstacle to overcome, and they have gone nuts with it.

If a car requires an average of 20 horse power for all types of driving then an engine designed to run at only 1 speed to produce 20 horsepower all the time would be interesting in many ways. Anytime the requirement is lower the energy could be stored and then used when the requirement exceeds 20hp. An ICE designed to run only at one speed can be tuned for very high efficiency and minimal pollution.

On the other hand say if you simply want to augment the electrical power requirements of an electric hybrid car, then a smaller ICE can be used simply to extend the maximum mileage between fill ups. To say 200 to 300 miles? What might be interesting is to have small ICE plug in options. You drive to work (round trip less than 40 miles) and you plug in every night so you can run on that alone. Or you plan to go out of town and plug in one small ICE (think Honda 1500 watt generator size) to go further, and maybe two for a long trip. The engines can continue to run when the vehicle is parked somewhere no plug in source is available, like when you stop for food. Here's a killer, the more your vehicle is not moving the longer the electrical range gets.

Issues not addressed - Home electricity comes from many sources, and many are not as clean as a modern ICE with a CAT, multiple O2 sensors, etc. How many engines like that will it take to match a coal fired power plant?

What about winter? An all electric vehicle? How does one purpose to stay warm? Have you noticed how much power is required for an electric space heater? We're not talking an amp or 2 here. How does one run a rear defroster? Or AC?

Author:  sea2stars [ Sat Aug 02, 2008 11:25 am ]
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Hrmm. From a few quick searches:

- Although Propane burns very cleanly, it gives about a 25% loss of power, and efficiency, compared to gasoline. Unless you use a higher compression engine.
- Below 50F outside air temp, it'll be difficult to start an auto running LP; often need a gasoline start first.
- More expensive per million BTU compared to diesel

Author:  aristide1 [ Sat Aug 02, 2008 11:55 am ]
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sea2stars wrote:
Hrmm. From a few quick searches:

- Although Propane burns very cleanly, it gives about a 25% loss of power, and efficiency, compared to gasoline. Unless you use a higher compression engine.
- Below 50F outside air temp, it'll be difficult to start an auto running LP; often need a gasoline start first.
- More expensive per million BTU compared to diesel


All valid reasons. When you say "more expensive" are we talking fractions?

Author:  sea2stars [ Sat Aug 02, 2008 1:40 pm ]
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Hrmm.. actually, I just looked up current prices and it looks like LP is slightly cheaper than diesel? A gallon of LP provides about 1.5 times less BTUs compared to diesel; I'm not sure on the HP comparison, but the gov states current LP vehicles getting almost similar MPG vs modern gasoline vehicles. Hrmm.. about a $3500 conversion to a gas engine to use LP, although operating costs are lower. Another issue is that LP is more volatile price wise.

Author:  jaganath [ Sat Aug 02, 2008 3:44 pm ]
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they're probably not using propane because the bottle would take up too much internal space; the Typ-1e is not exactly cavernous in its internal dimensions.

Quote:
What about winter? An all electric vehicle? How does one purpose to stay warm? Have you noticed how much power is required for an electric space heater? We're not talking an amp or 2 here. How does one run a rear defroster? Or AC?


These are all problems that the Chevy Volt development team are wrestling with right now. The crucial word there is "space heater", current HVAC systems waste a lot of energy just heating space, when what you really want to do is keep humans warm. so directional air vents to concentrate warm air from the HVAC on the occupants, and not just waste it heating up the whole car, which is just lost to the environment. just about everything on a car can be a lot more efficient than it is now, ie there is a lot of waste going on.

Author:  NeilBlanchard [ Sat Aug 02, 2008 4:14 pm ]
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Hello,

The way the Aptera Typ-1e (an all electric vehicle) heats and cools the interior is with a heat pump. It also has a PV panel to ventilate the interior to help, too.

Author:  aristide1 [ Sat Aug 02, 2008 4:30 pm ]
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But this method is probably cheaper, and it's here now.

http://automobiles.honda.com/civic-gx/refueling.aspx
and
http://www.myphill.com/

Very low cost per gallon. The Phill pump has many tax incentives, so buying it is less of a pain.

http://www.edmunds.com/advice/specialre ... ticle.html

Notice the lack of spontaneous generalizations in my post. 8)

Author:  sea2stars [ Sat Aug 02, 2008 8:20 pm ]
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Neat. Heat pumps are over 100% efficient, although the current generation are only useful down to about 30F. We're currently looking to replace our old oil furnace, after the house is properly insulated, with either a hybrid NG furnace/standard heat pump system or one of these heat pumps good to -15F; already have NG coming into the house.

Author:  aristide1 [ Sun Aug 10, 2008 4:00 pm ]
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http://www.gotohallowell.com/waterheater.html

In my attic during the summer this thing wouldn't even have to run, just sitting in the heat should do it.

The other thing is this heat pump hot water heater should act as an air conditioner if it's placed in the living area of a home. Wouldn't that be a shame? Haha.

Author:  colm [ Sat Aug 16, 2008 1:16 pm ]
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I still long for a 3 main boxer four, conventional ice engine. todays computer aided engineering. wow. As if every last one by every country that made it wasn't a winner. They WANT to run...there is nothing smarter. do the math and only lie to yourself claiming otherwise. (I have indeed argued over this..and NEVER lost).

but with this electric stuff, I would like to try one out for local errands.

Author:  AZBrandon [ Mon Aug 18, 2008 5:05 am ]
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sea2stars wrote:
Neat. Heat pumps are over 100% efficient, although the current generation are only useful down to about 30F. We're currently looking to replace our old oil furnace, after the house is properly insulated, with either a hybrid NG furnace/standard heat pump system or one of these heat pumps good to -15F; already have NG coming into the house.


In short, their claims are bogus. Don't buy ANY type of heating or cooling product without a certification number. In the USA, the ARI is responsible for certifications. Their website is www.ari.org.

Here's an example. The unit I just purchased and am having installed tomorrow in fact has an ARI number of 3068848. This means I can go to their search site here and enter that ARI number and see my equipment listed right there. Double click on the entry and you get a nice PDF you can print with the certification of the model numbers and what all it's ratings are.

Anything that claims it is over 100% efficient is a lie. That kind of BS is perpetual motion machine make-believe. It's easy to drop BIG money on replacing a home heat unit, so I wouldn't want you to drop $8000 or something and find out all you got is a 13 SEER regular old heat pump with a 10KW supplementary heat strip bolted up to it. Go to the website for a REAL heat pump company, like Goodman, or a good FAQ site like this one. If you visit that FAQ site, maybe head straight to the link for AHRI Ratings and read up on the importance of buying certified equipment, not smoke and mirrors.

(Edited to fix broken links)

Author:  jaganath [ Mon Aug 18, 2008 9:10 am ]
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Quote:
Anything that claims it is over 100% efficient is a lie. That kind of BS is perpetual motion machine make-believe


sea2stars just expressed himself in a confusing way. heat pumps are over 100% efficient in the sense that for a given input X of work, they can move 4X of heat (for example). to avoid the misunderstanding that this has caused, performance of heat pumps is usually expressed in terms of the COP (coefficient of performance):

http://en.wikipedia.org/wiki/Heat_pump#CoP_and_Lift

Quote:
When comparing the performance of heat pumps, it is best to avoid the word "efficiency" which has a very specific thermodynamic definition. The term coefficient of performance (COP) is used to describe the ratio of useful heat movement to work input.

Author:  sea2stars [ Mon Aug 18, 2008 3:58 pm ]
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*nod* We're probably just going with a natural gas furnace. The Hallowell system is just too new, although a few of the big boys are working on similar systems. Thanks for the clarification jaganath.

Author:  NeilBlanchard [ Mon Sep 08, 2008 10:00 am ]
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Hello y'all,

I want to try to list steps that car makers could/should take to improve the fuel efficiency. The most obvious would be to mold the plastic on the front of the vehicle to be smooth and round, with grill openings that are sized (and placed) only as required to cool the engine. Similar to the original VW Passat (though it could be "rounder" in the horizontal direction):
Image
...or the original Ford Taurus (ditto with the squared off front shape leaving room for improvement):
Image

:arrow: Sealing all the seams and joints (with gaskets or backing flanges) in the high pressure areas of the vehicle.

:arrow: Smooth & aerodynamic underside.

:arrow: Tire pressure monitor.

:arrow: Average & "instant" MPG displays, that are on all the time. (The xD uses the same display for the odometer, the two trip odometers, average MPG, instant MPG -- way too many things on one display! You have to toggle through them with a button that could not be a bigger pain to press...)

:arrow: Fully ducted cooling system, with the intake down low on the front, and the exhaust in a low pressure zone; minimizing the size of the radiator and the reducing the drag as much as possible.

:arrow: Throttle control that maintains even throttle in a user-set speed range, with minimal throttle increases to maintain the speed in that range.

:arrow: Higher gearing with 6-7 speeds (smaller engines need more gears to work efficiently); or CVT transmissions.

:arrow: Video cameras and screens in place of side mirrors.

:arrow: Efficient and effective fresh air flow through the vehicle, with intakes on a high pressure area, and exhaust vent(s) out the back of the vehicle into the low pressure wake zone, to reduce drag as much as possible.

:arrow: Automatic engine shut off and start up; at least with CVT (or automatic) transmissions -- and possibly with standard shifts, based on having both the clutch and the brake applied?

:arrow: Lean burn in low vacuum conditions.

:arrow: Store hot coolant in a vacuum insulated tank, to speed up warm-up time; a la what the Prius does.

:arrow: Coat all the window glass to exclude as much heat as possible.

:arrow: Make A/C on the defrost setting optional.

:arrow: Tighten up wheel openings, and always use aerodynamically designed wheels/covers, with rear wheel skirts (at least optional).

:arrow: Make roof racks removable. Years ago, I saw a "papoose" add-on storage system that locked onto the back of the car, with a single caster wheel to support the weight -- it tucked completely into the air flow behind the car; and it would be a great way to add storage space when needed; that did not affect how you drove very much.

:arrow: For new 4-cylinder engine designs, the crankshaft could be split with a hydraulic coupling that can automatically disengage two cylinders completely; saving all the pumping and friction losses, for situations when 2 cylinders are enough to provide the required torque to move the vehicle.

:arrow: Or, make every vehicle with a plug-in electric w/ serial hybrid ICE drive train.

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