Just been reported on our local BBC news that the AA now says that whereas the break even point for a diesel car used to be 14k miles per annum it is now an enormous 40k miles per annum :eek:

They said that Petrol is now the better option.

Does that include the difference in price of buying a diesel over a petrol, or is it purely down to miles done?

I'm guessing that includes the "premium" extra expense of buying a diesel over a petrol model.

Which fails to take into consideration the occasions when a petrol equivalent is not available (like with the Fabia vRS)

As far as I'm concerned, (having already bought our brace of cars) until the difference in fuel price is bigger than the difference in mileage achieved, Diesel still wins.

Just been reported on our local BBC news that the AA now says that whereas the break even point for a diesel car used to be 14k miles per annum it is now an enormous 40k miles per annum :eek:

They said that Petrol is now the better option.

How on earth can they say that.

It's total nonsense and the numbers don't add up

Does that include the difference in price of buying a diesel over a petrol, or is it purely down to miles done?

I would think it would take in the extra cost of buying thediesel car...

for example my car (sporting 1.9 m/jet) costs £700 more than the 1.4 petrol turbo sporting... performance is the same, tax is the same, and the petrol does 40+mpg, and the diesel does 50+ mpg....

that £700 would buy alot of petrol...... makes it quite even, when there is just a 10 mpg diffrence, and petrol is so much cheaper than deisel.... (maybe zolberg can do the maths for us )

Does that include the difference in price of buying a diesel over a petrol, or is it purely down to miles done?

Given that it was the AA I'd like to think that they'd done their sums.

Glad to see I made the right decision with the V6 then!!!

Glad to see I made the right decision with the V6 then!!!

lol

Anybody want to buy my TDi?

I have seen a Monaro VXR I want to buy

well, I've done mine, and based on Sharkrider's figures above, assuming

- 40 mpg for petrol and 50mpg for diesel is constant, of course

- £1.15 for petrol, £1.29 for diesel:

The diesel makes up for the extra £700 somewhere between 53k and 53.5k :eek:

Ah, but its not that simple. What about the extra residual value of the diesel?? What about the difference in servicing and maintenance costs?

I would think it would take in the extra cost of buying thediesel car...

for example my car (sporting 1.9 m/jet) costs £700 more than the 1.4 petrol turbo sporting... performance is the same, tax is the same, and the petrol does 40+mpg, and the diesel does 50+ mpg....

that £700 would buy alot of petrol...... makes it quite even, when there is just a 10 mpg diffrence, and petrol is so much cheaper than deisel.... (maybe zolberg can do the maths for us )

Ok , lets assume all the other costs are roughly the same - servicing , insurance and so on.

On those figures , using diesel at £1.33 and unleaded at £1.18 it would take 53000 miles to claw back the difference.

Ok , not so good for diesel , but diesels *do* still get back some of the extra cost when you sell the car on. If you get £350 more than the petrol when you sell it on then that's just 26500 miles before the diesel is in profit.

Now if you also bear in mind that that's fuel prices *now* and not for the whole life of the car. Obviously it's very difficult to predict what they will be for the next few years , but if we guesstimate an average price of £1.40 for unleaded and £1.55 for diesel then that's 34000 miles to claw back the full £700 or 17000 miles to get back the £350.

Now quite why the AA think you need to do those miles in a single year or whether you do them over two or three is beyond me.

One other thing that I'm sure we will see - the difference in prices between engines are because that's what people are prepared to pay , and not necessarily because a turbo diesel costs £700 more than a turbo petrol engine.

If the perceived savings of diesel cars are lower then people will expect to pay roughly the same as the petrol and manufacturers will have to drop prices.

well, I've done mine, and based on Sharkrider's figures above, assuming

- 40 mpg for petrol and 50mpg for diesel is constant, of course

- £1.15 for petrol, £1.29 for diesel:

The diesel makes up for the extra £700 somewhere between 53k and 53.5k :eek:

See my lengthy reply above why that isn't necessarily the correct answer

or to try and work out future fuel prices why don't we use average rises in both fuels over the last five years and work it out then.

diesel has risen far far quicker and why on earth would it suddenly stop rising at that rate?

if that view is taken then in 5 or 10 years time diesel will be double the price of petrol and not even a consideration.

I've done a few more calculations, based on fuel only.

comparing my 40.89 (average) mpg Ford Focus 1.6, and my 48 (average) mpg Fabia vRS

the Focus becomes cheaper per mile when Diesel is between 17 and 17.5 % more expensive than Petrol

At the moment (round here) we're looking at a 12% difference, so the Fabia's safe - for now !

DERV per 1000 miles @ 50mpg = 20 gal = 90 lts @ 1.32 (todays price here) = £118/1000 miles

Petrol per 1000 miles @ 40 mpg = 25 gal = 112 lt at 1.19 = £ 133 per 1000 miles

fuel cost saving of £15 per 1000 miles for DERV

DERV car costs say £1000 more than petrol car but if both depreciate at the same rate you will get some of that back.

If £16,000 DERV car halves in value = £8000

if £15,000 Petrol cat halves in value = £7500

So car has cost an extra £500.

£500 divided by £15/1000 miles = 33,000 miles to recover additional cost of purchase.

Even IF you don't get any of the additional cost of buying the DERV car back (which is unlikely) yje break even point would be 66,000 miles or 22,000 year over 3 years.

If you want to get picky you could factor in interest on the additional £1,000 or difference in servicing costs but this will likely average its self out.

What you can't put a price on is the sheer (in my opinion) improved "driveabiliy" of the DERV:)

or to try and work out future fuel prices why don't we use average rises in both fuels over the last five years and work it out then.

diesel has risen far far quicker and why on earth would it suddenly stop rising at that rate?

if that view is taken then in 5 or 10 years time diesel will be double the price of petrol and not even a consideration.

Ah.... but 5 or so years ago diesel was actually cheaper than petrol. If production capacities level out with demand (and the laws of supply and demand usually work) then there is reason to expect at least parity in future prices

Ah.... but 5 or so years ago diesel was actually cheaper than petrol.

er, thats my point exactly :confused:

er, thats my point exactly :confused:

agreed but second sentence of my reply question wether the current price difference will be maintained.

Ah, but its not that simple. What about the extra residual value of the diesel?? What about the difference in servicing and maintenance costs?

Well, petrol cars have far fewer needs for a fuel filter change than a diesel and other than sparkplugs & HT leads (which if half decent should last for ages) I cannot think of any additional costs for a petrol service over a diesel?

Furthermore, you mention the residuals . . . which presumably were originally mainly to do with the desireability of a "more economical" diesel. As has been calculated, if this is no longer the case, perhaps the residuals of derv cars is about to plummet relative to the petrol models?

Ah.... but 5 or so years ago diesel was actually cheaper than petrol.

Nope , it was slightly more expensive than unleaded (2p) back when I got my first Octy and that wass just over 5 years ago

It would be interesting to see what the basis of the figures is. For instance, you'd assume they use the EC combined economy figure, and how many drivers get that sort of economy? Is it easier to drive a TD hard and get good economy compared to a petrol?

Also, iirc, the service intervals on diesels used to be shorter than petrols so why have they equalised? Better technology or pandering to the fleet market?

Nope , it was slightly more expensive than unleaded (2p) back when I got my first Octy and that wass just over 5 years ago

That's because diesel carries 2p more tax a litre than petrol

or to try and work out future fuel prices why don't we use average rises in both fuels over the last five years and work it out then.

diesel has risen far far quicker and why on earth would it suddenly stop rising at that rate?

if that view is taken then in 5 or 10 years time diesel will be double the price of petrol and not even a consideration.

No derv is only more at the moment because more people want it and they have not changed the cracking towers over. If enough refineries build dierv producer not petrol primary stacks more derv would be around and prices would reduce. Then with less people using derv as petrol is cheaper the price of derv will reduce further.

TBH when the price of oil goes up and the price of petrol doesn't change but derv does, you kind of know the fuel companies are playing silly buggers IMHO.

It would be interesting to see what the basis of the figures is. For instance, you'd assume they use the EC combined economy figure, and how many drivers get that sort of economy? Is it easier to drive a TD hard and get good economy compared to a petrol?

Also, iirc, the service intervals on diesels used to be shorter than petrols so why have they equalised? Better technology or pandering to the fleet market?

I can only speak for myself , and I do get (or slightly beat) the combined figure.

Also in my experience , I find that diesel economy doesn't suffer as badly when pressing on as a petrol car would do.

As for the servicing - I'm getting 18-19k between services on my octavia. A lot of manufacturers have pretty standard 12.5k service intervals on both types of engines.

At the end of the day there isn't a single right answer for everyone.

**some** diesels are now as expensive to run as petrol equivalents - a friend bought a Kia Carens a few years back and the petrol claimed about 34mpg and the diesel was only 38 which is a very small difference.

With the 11% diesel surcharge (an artificial gap introduced by fuel companies) they basically would be the same to run per mile , with no way of recouping the extra cost of the oil burner.

I'm also thinking that the 40 mpg from a petrol is at the decidedly good end of economy for a such a car and the 50mpg quite poor for a diesel.