Most fuel efficient car?

Kelter

I know some may say this belongs in the Motors section, but I really think its fits better here.

I will be changing my car in the next few months and am in the happy position of being free to change it to whatever car I like. My main criteria is that it be the MOST fuel efficient car on the market. I've been considering some of the choses available - hybrid, flexifuel, small diesel, but was just wondering if someone has really done the work on this before?

So if is a diesel Corsa, I'm happy, or a Prius, I'm happy...

but if its a Smart Roadster... I'm really really happy

Kali

Audi A2 1.2TDI.

Kelter

Thats cool. Cheers, but I can't find a single one available.

gonk

Nissan Micra 1.5 diesel should get in excess of 60mpg - doesn't seem to be listed on Nissan Ireland website, may only be available second hand.

alias no.9

Citroen C2 1.4HDi

5.1l/100km or 55.3mpg urban
3.6l/100km or 78.4mpg extra urban
4.1l/100km or 68.8mpg combined

Fabritzo

Seat Arosa Diesel?

Honda are launching a civic hybrid soon, it should be impressive.
The Punto diesel might be woth a look too

Do-more

alias no.9 wrote:

Citroen C2 1.4HDi

5.1l/100km or 55.3mpg urban
3.6l/100km or 78.4mpg extra urban
4.1l/100km or 68.8mpg combined

VW Lupo diesel beats that, there was a version called the 3 litre as it only used 3 litres of diesel/100km (about 85mpg) don't know it was ever available in Ireland just Germany probably. Lupo no longer available new however, replaced by Fox which is only available here with petrol engines.

CJhaughey

VW Polo Dune 1.4TDI 70 PS ,comes in at 60.1 mpg which is not bad.

Do-more

Here's a chart I found showing MPG and CO2 emmissions for current new cars

http://www.vcacarfueldata.org.uk/information/how-to-use-the-data-tables.asp#petrol

So your choice is down to a Toyota Prius hybrid or a Citroen C1 Diesel depending on the criteria you use...

CJhaughey

That Lupo 3L was economical but talk about miserly in terms of equipment and spec, it had no power steering, or anything that might cause more engine load.
I guess thats why it didn't sell well.
The Polo is a much more refined car by comparison.

mike65

I'd stay well clear of the Prius, extra engineering, more to go wrong in later life. High price (€29,580) dispite the government VRT drop.

Mike.

bonkey

Kelter wrote:

but if its a Smart Roadster... I'm really really happy

Even if it had won...they've discontinued it. Although I think some English or Welsh crew has bought the rights to it off them and will continue producing it, or some veriant of it.

What a car.

jc

Do-more

bonkey wrote:

Even if it had won...they've discontinued it. Although I think some English or Welsh crew has bought the rights to it off them and will continue producing it, or some veriant of it.

What a car.

jc

You could probably pick up a 2nd hand one pretty cheap out at Merlin they have a liquidation sale of the assets of Parkwest Autopoint on Tuesday, no reserves!

http://www.merlincarauctions.ie/contentv3/index.cfm?fuseaction=page&pageID=9145

Scroll down for the '03 Smart with 5,500mls.

Nukem

Came across this from Mayo Energy

http://www.mayoenergy.ie/Home2/EnergyTips/PDFFile,2561,en.pdf

road_high

Any of the Daihatsus are very good on fuel. My ma had a Charade before and it was very economical indeed. And they're super reliable- don't why they're shunned by Irish buyers.
I've a diesel VW Bora diesel and I get 50 mpg consistently. Any of the VW diesels would be similiar.
The Prius is overhyped and not especially economical, 35-40 mpg. It's just in the States where it's popular this kind of mpg is brilliant.

krinpit

This seems like the place to post this question:

I'm currently comparing a 1.6 Petrol Bora or a 1.9 SDI Bora for mainly rushhour city driving. One weekend a month, there would be a 400 miles round trip.

Forgetting about the price of car and tax/insurance etc, would a diesel always be more efficient than a petrol, given the scenario?

luapenak

subaru vivio.
suzuki alto.

Capt'n Midnight

mike65 wrote:

I'd stay well clear of the Prius, extra engineering, more to go wrong in later life. High price (€29,580) dispite the government VRT drop.

Mike.

Also it takes a lot more energy and resources to build and recycle it so a lot more CO2 over it's life. Also firemen have been electrocuted in the past when cutting the battery cables.

Capt'n Midnight

krinpit wrote:

Forgetting about the price of car and tax/insurance etc, would a diesel always be more efficient than a petrol, given the scenario?

Yes.
A diesel engine weighs more than a petrol engine of the same power and uses a bigger battery. Otherwise the weights of the car and fuel system are more or less the same. So petrol has the slight edge on Kerb weight.

The main difference between diesel and petrol is in the way the fuel is burnt. For a petrol engine it's isometric, one bang and the fuel is burnt before the piston can move very far.
For a diesel engine it's isobaric, the fuel is burnt more evenly as the piston moves.
It doesn't seem to be much of a difference but you just don't see that many petrol engined trucks, coaches, ships or locomotives.


http://imartinez.etsin.upm.es/bk3/c17/Power.htm

{petrol} Typical energy efficiencies are low, 25% to 35% when running at nominal power, and much lower at partial load, but the engine is light, very powerful and responsive (accelerates very quickly), and not as expensive as diesels

The 35% is when the engine is at full power, for example when you are accelerating up a hill. During normal driving the efficiency is lower because you are sucking more unneeded air into the engine, diesels do the same but since they rev slower there isn't as much drag on them.

{Diesel} It is the reference engine from 50 kW to 50 MW, due to the fuel used (cheaper and safer than gasoline) and the higher efficiency.
...
Typical energy efficiencies are from 30% to 54% (based on the lower heating value of the fuel)

Note the 54% is for engines at the 50MW range.

Energy and exergy efficiencies of 36% and 50% respectively have been reached with prototype Stirling engines of up to 10 kW, the main problems being the regenerator loss of efficiency at high speeds (>30 Hz, i.e. >1800 rpm), the radiant heat looses at high temperature (>1000 K), incomplete exchange of gas between the hot and cold zones, and leaking at high pressure (>5 MPa).

Stirling engines may take off if the engineering problems are solved. Their many advantage is that you can use just about any fuel - it doesn't need to be a clean dust free fluid. Note the stirling engine can reach Diesel / steam turbine efficiencies at much lower powers.

Lennoxschips

Nice list here:
http://www.autoweek.nl/carbasetopindex.php?cache=no

You can search the database for a Top 100 list for lowest fuel use "laagste brandstofgebruik". You can select a year of production under "jaar". You can also specify the engine type "diesel" or "benzine" (petrol) under brandstof. It would appear that the two most economical cars, the VW Lupo 3L and the Audi A2 1.2 Diesel are no longer in production.

You can also select a price range, but that's only the list price when new, so not much use for older cars as some types depreciate faster than others, but good as a guide.

Lennoxschips

This Polo is a nice one. More fuel efficient than a Toyota Aygo, if the numbers are to be believed.