Will We Have a 100-mpg Car Soon?

sentiententity · Post by **sentiententity** » 31 Mar 2008, 21:04

So the following aren't your words then:
[peurile editing] wrote:

Although we can't calculate efficiency ([Energy in/Energy out]x100%) until we know how much the car got out of the mains when the battery was charged, we do know that we are probably not more than doubling it.

Of course they are. And as you can see, there is no efficiency number there, pulled from the air or meticulously-derived with all working shown. (Hint: such a number would look like "efficiency of x%", where 0<x<100). However, I have included the equation for calculating energy efficiency, which may well come in handy later. That was nice of me.

Woolly thinking.
They DO only use one gallon.
That part of the energy to move the vehicle comes from elsewhere doesn't increase the number of gallons used.

Woolly thinking indeed. Just because the energy comes from somewhere else does not mean it can be ignored. We are not making the vehicle more efficient here, so that it can achieve more with the same amount of energy, we are providing another source of energy. This is the important thing. It does not matter whether it is provided as petrol, or diesel, or electricity from a power station, or what. You are providing more energy to start with - and then not counting it all!

What is "true mpg"? It means what it says it means "miles per gallon".

We are trying to compare this car with other (single fuel) cars, whose efficiency is measured in mpg. You are providing another source of energy, which you are not taking account of, so you are claiming ludicrous mpg values. Energetically, what you are doing is the same as fitting a diesel engine in the boot of a petrol-engined car, and then claiming that you have doubled its efficiency (mpg), because you only count petrol that goes in and not diesel. Or think about it another way: pull the Prius' back seat out and use the space for another rack of Li-ion batteries. Do you really think you have improved the efficiency of the car? (As opposed to increased its capacity before having to switch to the petrol engine). Do you think you can meaningfully add another 50 mpg to the claimed mileage?

You don't understand what's happening here and are confusing the whole thing. Which is exactly the problem.
1. There STILL is only one gallon of petrol going in.
2. An electric engine is more efficient than an ICE for the non-petrol part.

More ENERGY is going in. And this is the important thing.

There's no need to be snotty.

On the contrary. Decision makers read this site

Well it seems unlikely that they would be impressed by gratuitous insults from people with such a tenuous grasp of concepts like energy and efficiency.

s.

sentiententity · Post by **sentiententity** » 31 Mar 2008, 21:20

Re. idiocy from Dan McNeil:

From the Car magazine article:

It means you could commute 15 miles each way in a city and have no fuel costs at all, BAR THE OVERNIGHT CHARGE. At Powergen's current price, that's only 21.9p.

Which bit of energy coming out of the wall and into the car are you and Fifthcolumn unable to get your heads round?

s.

Dan McNeil · Post by **Dan McNeil** » 31 Mar 2008, 21:35

senile-entity said:

From the Car magazine article:

Poor old econut, he's all tip and no iceberg.

Listen old chap - all I did was post a link to Auto Express (not Car - still having trouble reading, I see). I've made no fancy and unverifiable claims - that's clearly your area of expertise. That, as well as getting all hot and bothered with the idea of making everybody cycle everywhere, whether they're alive or dead or have only one leg.

I suspect your obsession with efficiency masks an unhealthy hatred of cars. You need to chill out a bit.

JohnB · Post by **JohnB** » 31 Mar 2008, 21:54

Maybe when TSHTF all these hi-tech cars will be parked in their owners gardens being used as greenhouses, because the resources aren't there to maintain them, and the only cars on the road will be Morris Minors and their contemporaries because they can be fixed with a hammer and a few spanners

.

sentiententity · Post by **sentiententity** » 31 Mar 2008, 22:29

with the idea of making everybody cycle everywhere, whether they're alive or dead or have only one leg

You need to stop lying.

I suspect I may have been trolled.

s.

fifthcolumn · Post by **fifthcolumn** » 01 Apr 2008, 11:18

sentiententity wrote:Of course they are. And as you can see, there is no efficiency number there, pulled from the air

So you didn't say "can't be more than double".
That sounds like an efficiency rating pulled from the air to me.

Woolly thinking indeed. Just because the energy comes from somewhere else does not mean it can be ignored.

When you are talking about solving a shortage of liquid fuels YES IT CAN.

We are not making the vehicle more efficient here, so that it can achieve more with the same amount of energy

You haven't even bothered googling "well to wheels" have you?
You're not even worth talking to because you think you can model the world in your head and consider yourself smarter than those who have already done the work. That's dangerous because someone with the ability to make decisions could listen to you.

We are trying to compare this car with other (single fuel) cars, whose efficiency is measured in mpg.

Correct. Note it says miles per GALLON.

Energetically, what you are doing is the same as fitting a diesel engine in the boot of a petrol-engined car, and then claiming that you have doubled its efficiency (mpg), because you only count petrol that goes in and not diesel.

That is exactly the same error as the clowns who misunderstand the EROEI concept.
No. Diesel and Petrol are the same type of energy.
Fossil fuels.

Well it seems unlikely that they would be impressed by gratuitous insults from people with such a tenuous grasp of concepts like energy and efficiency.

Decision makers are quite likely to insult people like you who open their mouths without confirming they know what they are talking about and with nothing to back it up.
I consider you to be a dangerous idiot.

sentiententity · Post by **sentiententity** » 01 Apr 2008, 17:51

That sounds like an efficiency rating pulled from the air to me

That's because you don't understand the concept of efficiency. Even though I helpfully included the equation for you. Sigh.

Me:Just because the energy comes from somewhere else does not mean it can be ignored.

Fifthcolumn:When you are talking about solving a shortage of liquid fuels YES IT CAN

We are not just talking about that. Peak Oil will have other effects apart from making it a bit harder to drive the 2 miles to B&Q and back on Saturday. Try reading around the subject, and you will be sure to see this. Also, burning fossil fuels, whether in infernal combustion engines

or power stations, is causing another problem that you may have heard of.

Me:We are not making the vehicle more efficient here, so that it can achieve more with the same amount of energy

You didn't answer this, revealingly, just started throwing insults.

...misunderstand the EROEI concept. No. Diesel and Petrol are the same type of energy. Fossil fuels.

I understand EROEI. Selective editing: why didn't you reply to this:

think about it another way: pull the Prius' back seat out and use the space for another rack of Li-ion batteries. Do you really think you have improved the efficiency of the car? (As opposed to increased its capacity before having to switch to the petrol engine). Do you think you can meaningfully add another 50 mpg to the claimed mileage?

Surely I couldn't make it clearer? Pull out the ICE and run the Prius just off its batteries. Do you have:
(a) a car that gets infinite miles per gallon? or,
(b) an electric car?

I will ignore gratuitous abuse, just ask, re. EROEI: Do you think it is intelligent to, say, build a nuclear power station to provide the steam for melting tar sands?

s.

fifthcolumn · Post by **fifthcolumn** » 01 Apr 2008, 18:22

sentiententity wrote: snip

Conversation closed.

RevdTess · Post by **RevdTess** » 01 Apr 2008, 18:34

Someone needs to convert everything to barrels of oil equivalent or kwh and publish their sums. I for one have no idea even how an electric car charged off the grid compares to a gasoline or diesel car in terms of a) cost per mile or b) energy per mile. Anyone got the numbers or a link?

Vortex · Post by **Vortex** » 01 Apr 2008, 18:39

Err .. I thought I was on PowerSwitch .. somehow I have bumped into a PO.COM thread ....

Bedrock Barney · Post by **Bedrock Barney** » 01 Apr 2008, 20:03

Ha!, exactly what I was thinking. Do we need a Hall of Flames here?

Andy Hunt · Post by **Andy Hunt** » 01 Apr 2008, 21:34

Just goes to show, maybe it is the end of the world after all.

Doooooooooooooooooooooooooom

Bandidoz · Post by **Bandidoz** » 05 Apr 2008, 11:10

Tess wrote:Someone needs to convert everything to barrels of oil equivalent or kwh and publish their sums. I for one have no idea even how an electric car charged off the grid compares to a gasoline or diesel car in terms of a) cost per mile or b) energy per mile. Anyone got the numbers or a link?

Here's a fag-packet approximation:

A litre of petroleum is approximately 10kWh.
The traction used in the Toyota Prius is in the order of 45kW.
So you could summise that driving the Prius for an hour (45kWh) would use the energy equivalent of approximately a gallon.
The Prius can do approximately 60mpg - so that gallon equivalent is roughly 60 miles, and it would roughly take an hour at 60mph.

So taking 45kWh to be the energy equivalent:

a) That's 45 units of electricity (assuming no battery losses) - so at 10p per unit that's ?4.50

b) That's a gallon of petrol, at ?1 per litre that's also ?4.50, assuming the petrol-driven car is 60mpg.

Hope that helps.

Bandidoz · Post by **Bandidoz** » 05 Apr 2008, 11:22

Dan McNeil wrote:clv101 said:

I don't understand this. 100mpg is almost twice 55mpg. How does a different battery pack manage to get almost twice the work out of the same fuel? The engine is the same, the duty cycle can be improved a bit, but I wouldn't have thought anywhere near a doubling.
The standard battery and electric motor can run the car for around 3 miles without using the gasoline motor, after which the battery has run down, causing the gasoline motor to start up to recharge the battery. The lithium battery can power the car for around 30 miles without using the gasoline motor. The clue is in the term MPG ...the car is basically travelling more miles without using gasoline, hence increased MPG.

The drawdown of electric charge should not even be considered to be part of the MPG. Otherwise you could suggest that it has infinite MPG if you just do a 100m trip down the road; which is clearly ridiculous.

I suppose the impact a different battery pack could have is that it may weigh a lot less than the standard model?

Ballard · Post by **Ballard** » 05 Apr 2008, 13:42

You can of course easily quadruple the efficiency of the standard car?

By placing four people inside it.