Peugeot Electric

bikeboyz · Unread post by **bikeboyz** » 16 Mar 2005, 00:23

Has anybody driven a Peugeot 106 Electric? or any other PSA EV ?

fastandfurryous · Unread post by **fastandfurryous** » 16 Mar 2005, 01:12

Our university site support used to have a peugeot 106 electric van. It was creepy the way it would just move off from stationary in almost complete silence. I don't think it was particularly powerful, as it never seemed to accelerate very quickly, and the bloke who used to drive it was a complete chav, who no doubt drove it foot to the floor.
The stupid thing about electric vehicles is that they are possibly the most ineffeicent power source for a vehicle, and are more polluting than a combustion engine. Before anyone starts shouting "But they don't produce any pollution at all!!" have a gooood think about where the electricity comes from, the effecieny of the national grid, the efficiency of battery chargers... etc etc....

Kowalski · Unread post by **Kowalski** » 16 Mar 2005, 15:27

Power stations are relatively efficient at producing electricity and relatively clean in terms of emissions. Diesel engines are comparable on efficiency, petrol are worse. The advantage of electricity is that the pollution is produced elsewhere, so it looks cleaner when in fact it is worse, it helps with city air quality but causes more CO2 to go into the atmosphere.
Gas is looked upon as a green fuel when in fact an LPG vehicle produces more CO2 than the equivilent diesel, it burns cleaner but you need to burn more of it.
As clean sustainable fuels go, the only sustainable solutions are either nuclear or biofuels. In the UK wind and water power are just a distraction, they can't produce anything like enough power without destroying the land (who wants a wind turbine on the top of every hill?)

fastandfurryous · Unread post by **fastandfurryous** » 16 Mar 2005, 17:46

It's a big problem isn't it.
I still find this rather an interesting calculation to do for an electric vehicle:
Efficiency of Electricity generation ~ 45% (on a good day)
Efficinecy of the national grid - 90% (yes, they loose 10% of their power! most of the grid runs quite warm, up to 60c!)
Efficiency of the battery charger - 75% for a good one.
Efficiency of Lead-acid/Nickel cadmium batterys ~70% (you have to supply a lot more Joules of energy to charge them than you get back)
Efficiency of Electric motors ~ 95%
Thus making an overall thermal efficiency of only 20%. Pretty crap when you consider a diesel engine can be up to 40% efficent (or even more with a modern HDI)
My main pet hate is that Biofuels, such as rapeseed oil and transesterified Bio-diesel still attract exise duty at rates far higher than that of LPG. You only have to look at the attitude of fatty-two-jags during the fuel crisis 4 years ago to have a good idea of the government's attitude.
*steps down from soap-box*

Kowalski · Unread post by **Kowalski** » 16 Mar 2005, 19:05

38% is considered very good efficiency for a thermal power station, only the biggest ones acheive such high efficiency. Car diesel engines offer similar efficiency at full load and only at full load, only larger diesels can be more efficient (think generator sets).
I don't know what the overall efficiency of a diesel car works out at since the engine doesn't manage to run at full load all of the time, in fact it runs at part load the vast majority of the time and at low part loads engine efficiency is poor to say the least, the engine needs fuel to idle with no load, i.e. it can operate at 0% efficiency at times.

jeremy · Unread post by **jeremy** » 16 Mar 2005, 21:56

My understanding was that about 30 years ago a large diesel engine (which I imagined meant ships) could run at up to 48%. All diesels at that time smoked to some extent and of course the smoke is unburnt or badly burnt fuel - so with better injection systems, more available air etc the efficiency should increase considerably.
I don't know what the current efficiency of car engines is supposed to be but clearly it varies as the consumption of similar cars with different running gear varies. (TD and HDi Xantia for example)
Of course conditions of measurement will produce differing answers - part/full throttle etc.
Anyone here a thermodynamics expert?
jeremy

Kowalski · Unread post by **Kowalski** » 16 Mar 2005, 22:02

You only need a small amount to fuel to produce a lot of smoke, smoking isnt really a cause of poor fuel economy unless its pretty bad. The laws of physics don't change but design of engines does improve.
Check this link out,
http://www.bath.ac.uk/~ccsshb/12cyl/
This is the most powerful diesel engine in the world, it's thermal efficiency is about 50% which is pretty competitive.
Large diesel engines can be more efficient than smaller ones because the surface area to volume ratio decreases as the engine gets bigger, so less energy is lost as heat through conduction into the metal engine components.
At 50% efficiency its more efficent than a typical coal or gas fired power station. Why don't they use such engines to generate electricity, using gas?

mbunting · Unread post by **mbunting** » 16 Mar 2005, 23:13

Well, in my mind, it's much easier to change a polluting powerstation for a low pollution one ( such as nuclear / wind / solar / hydro / geothermal ), and within the space of a year to 18 months dramatically reduce pollution, than it is to make loads of fossil fuel cars more efficient overnight.
Of course, you do have to convince people to dump fossil fuels in favour of all-electric.

yangreen · Unread post by **yangreen** » 17 Mar 2005, 02:16

And there's the problem. I've never got excited over the sound of an electric car. Granted, I really don't understand why the sound of a V8 screaming lifts the hairs on the back of the neck but it does! An electric motor will never give that thrill.
Oh I noticed that in the budget, fuel tax was frozen. Not brave enough to increase it just before the election!
As for engine produced national electricity, imagine the gearing to get 102rpm up to a high enough speed to generate enough electricity! It must have one hell of a starter motor...

fastandfurryous · Unread post by **fastandfurryous** » 17 Mar 2005, 03:00

Actually, Modern Gas fired electricity generation can achieve between 50% and 55% thermal effeciency. This is due to them being a "hybrid" generating station. Gas is burned to power a gas turbine engine, thereby generating electricity. The thermal effeciency of this process is poor, Maybe about 30% at best. The clever bit is if you use the "waste" heat from this process to raise steam, and then operate steam turbines, as in every other coal/oil/nuclear power station. This process (which we are quite good at) can be up to 40% efficient, so as an overall efficency, you are looking at over 50%.
When you combine these modern stations with the old generation of coal/oil/nuclear stations still running all over the UK, at an effeciency of between 35% and 40%, this is where I came up with the estimate of 45% efficiency as an average (ish!)
Reciprocating piston engines are rarely used for base load elecricity, as you have the problems of huge mechanical complexity, and frequent maintainence. Turbines are much more reliable, have far fewer moving parts (Only one really.. the rotor!), and don't need oil changes every few hundred running hours.
I once calculated the overall thermal efficiency of a car, relating the Load (Wind load, Rolling resistance, etc.) to the fuel map of the engine. For "average" useage... (some round town, some motorway) I think it came out at about 30% overall efficency in the end, although there were a lot of assumptions made. One thing that was noticeable was that even on part load, a diesel engine is still surprisingly thermally efficient.
The real reason we don't have green energy at the moment is because too many companies are making too much money out of fossil fuels, Governments only ever think in terms of the next election, and at the moment, the technology is still too expensive. (plus all the NIMBY crews..)

gardenpeas · Unread post by **gardenpeas** » 17 Mar 2005, 03:24

around coventry the university and royal mail use pug vans you can't hear the things coming not good for us students who don't look just listen think they come with better brakes

bikeboyz · Unread post by **bikeboyz** » 17 Mar 2005, 04:15

I was really just thinking of a "something different" run around more than anything. More web reading though shows Peugeot wont sell you one, unless you are a company - then you have to lease the battery. Electric mopeds seem ok no same speed as a petrol engine, but dont fancy it. Citroen Berlingo vans apparently can be bought by anybody... another lovely odd PSA COAPUIAB!

fastandfurryous · Unread post by **fastandfurryous** » 17 Mar 2005, 04:49

COAPUIAB?

bikeboyz · Unread post by **bikeboyz** » 17 Mar 2005, 04:55

Couldn't organise a P*** up in a brewery.