Safe Speed Forums

Given the current high fuel prices, how can people drive more economically?

A few suggestions:

• Avoiding frequent stopping and starting and maintaining a reasonably steady pace is important. It isn't necessary to drive excessively slowly - cruising at 40 may not save any fuel as against cruising at 50. In most cars you won't find much fuel penalty from cruising at 70 on the motorway, but above that the consumption does tend to decline fairly rapidly. Having said that, 80 on the motorway will still be much better than grinding through heavy urban traffic.
  
  
• Avoid harsh acceleration, but aim to accelerate reasonably briskly up to your desired cruising speed and then consider a block upchange from third to fifth.
  
  
• Don't leave the car unnecessarily in low gears, but letting the engine labour at very low revs in high gears isn't generally a good idea either.
  
  
• Modern fuel-injection engines will cut off the fuel completely with the foot off the gas, so aim to just drift down long downgrades with no accelerator pressure.
  
  
• Good anticipation to avoid the need for heavy braking and then accelerating again always helps - if you think the lights may soon change to green, there's no point in rushing up to them and then stopping.
  
  
• When stopped for more than a few seconds at traffic lights, put the handbrake on and the gears in neutral - don't ride the clutch.
  
  
• In general, smoothness is more important in saving fuel than slowness as such.

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

I am in a fairly fortunate posistion of not having to drive much, my commute is half a mile and town isn't that far away. As fuel gets more expensive I just drive less what with only having a finite amount of money. I have pollitical reasons too for buying too much petrol, Mr Brown will blink first...

Anyway I have also dramaticaly altered my driving style and seen town driving, which is all 5 miles or less to the shops go from 33mpg to a knats under 40 on the last tank full and my motorway trip to my family go from 34 to 45.4 . It's mostly down to what Peter has mentioned, just rolling along using plenty of forward planning. I am driving alot slower. My car doesn't tell me how much it is using so it only comes to light when I fill up, so I can't really tell how much effect speed has on thirst. On my last trip to Shropshire my speed was 20 mph slower than normal, but oddly it was one of my quickest journies. There just seemed to be less traffic.

Are people driving differently now? Less, slower? What effect of KSI's? Something else I thought of today is.... the anti car lobbies have long wanted high fuel prices and basicly want to tax/charge us off the road. Now this is happening, but it is having an effect of the ecomony. Do the anit car lobbies still want us off the road regardless of the effect on the economy or do they concede that the economy needs personal transport?

The day I feel compelled to start driving in an "economical" way is the day I will hang up my keys. If fuel was double what it is now I would still drive the same.

If you need to save money buy one of the cheap jack sh*t minis that are on the market. You can even lease them for less than £100 a month and will only cost you about £36 a year in tax.

To take you up on your last point anti-car lobbies are what they say.... anti-car. Since they are also, from what I have seen, anti motorcycle (even though some of these get more than 100 mpg) they are opposed to personal powered transportation full-stop.

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Speed camera policy Kills

It must be nice to have such deep pockets as you.

However it is a fact of life that the current level of fuel prices are causing problems for many people and they can alleviate those problems to some extent by driving in a more economical manner. If you anticipate things better this need not result in any slower times from A to B in real-world journeys.

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

Got any tips on how to reduce my mortgage?

If I find any, I'll let YOU know!

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

Thanks for those Peter. I was aware of most of them, but had thought that accelerating very gently rather than briskly was the way to economise (I'm not arguing, I'm just saying thanks for correcting me! )

I try to put these things into practice sometimes, just to see how little fuel I can use, and it does make a huge difference. Mind you, the last time I did it, 40 miles on an effectively empty M4 at 65mph was far from stimulating (it was the small hours...even the M4 becomes empty then! )

BTW Peter, in your first bullet point, I think you may have intended to say "consumption does tend to rise fairly rapidly" instead of "decline" (though I'm sure it's obvious to everyone what you meant).

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Paul Smith: a legend.

"The freedom provided by the motor vehicle is not universally applauded, however: there are those who resent the loss of state control over individual choice that the car represents. Such people rarely admit their prejudices openly; instead, they make false or exaggerated claims about the adverse effects of road transport in order to justify calls for higher taxation or restrictions on mobility." (Conservative Way Forward: Stop The War Against Drivers)

I've seen this in several places - I think the idea is to get to your desired cruising speed reasonably quickly.


That's where cruise control comes into its own, of course.


Yes, mpg declines, so of course consumption rises

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

My car is still reliable but has just about finished depreciating (it isn't costing me £100/ month and I don't do leasing) so fuel is easily the biggest cost, and one which I can economise on to some extent. One could easily get through £3k/yr in unleaded @£1.14/litre. I don't really want to have to alter my driving style to "economy mode" either, but I have pay for my own fuel and needs must.

I have a modern (new) diesel MPV and an old (early 1990s) petrol car.

I'm sad to say that the diesel just uses less fuel the slower I drive it. It does about 35MPG at 80, 37MPG at 70, nearly 40MPG at 60, and so on. I haven't found the speed at which it stops getting more economical but I think it's probably a constant 30 or thereabouts. Trouble is, it's pretty much impossible to do a constant 30 anywhere these days (well, not without being incredibly selfish and dangerous anyway)! I once got 45MPG following a timid relative along an NSL A road for about 80 miles at 40-50.

I think the reason that accelerating moderately rather then gently tends to give better fuel consumption (at least in petrol cars) is because the throttle plate is open further and the volumetric efficiency of the engine is better because the cylinders are filling better. Full throttle is very thirsty because most engine management systems give excess fuel when the throttle is wide open.

The petrol car definitely has an optimum speed of about 50MPH. Any slower than that and it doesn't like 5th gear. Keeping it in top gear makes much more difference than the diesel.

Although I take the point about over-run fuel cut-off, I fid that the most economical way on gently rolling constant speed roads is to let the car run away a little on the downhill bits rather than lift off completely and then use that momentum up the hills - slowing down on the hills so that the engine isn't working hard against gradient AND wind resistance. The diesel has a fuel computer and kicking it into neutral on a long downhill is significantly worse than lifting off (because it uses fuel whilst idling when I put it in neutral). Lifting off the throttle completely and leaving it in gear as long as possible before declutching helps for this reason too (even if it's not as safe as being in a lower gear and using the engine as a brake).

Finally, (and pretty obviously), all the usual things - remove roof racks / cycle racks etc, keep tyres as hard as allowed in the handbook (I use the "full load" setting even when empty), minimise the use of aircon, don't cart loads of junk that you don't need around in the car all the time. etc etc.

I drive as efficiently as I can.

Other tips include:
- Preempting traffic lights (although it's not as fun as when I cycled and would zoom past cars).
- Approaching roundabouts in 2nd gear, fine tuning the speed to find a gap, almost like merging with a slip way.
- When cruising at say 60mph, keep your accelerator at the same level while going up hills and let the car naturally slow down and later speed up.
- Get off the gas earlier and gradually slow down for things - some less intelligent drivers will get annoyed despite the fact you often catch up with traffic or arrive just as it's going and thus saving in fuel. (Careful they may not be going the same way as you and have every right to be annoyed if you've delayed them).
- Pull in and park going forward and a place where you can drive out forward. I park on a back road 15 minutes walk from my school for these reasons and it has no parking restrictions . Most people park near the school and have to move their cars and pay more in fuel and the odd parking ticket. I still have people to walk with to where I park though.

Someone once told me to think of the BRAKE as the pedal that used the most fuel.

-which was one of the best economy driving tips I ever got!

economical driving is harder than point & squirt - recall Mr. Clarkson in his 800 mile trip on a single tank - he said if every driver drove with this level of concentration, there would never be a road accident!

Anyway, all good tips; my personal mantra is smooth, as real smoothness covers all of the bases. I mentally listen to the Santana / Rob Thomas track as I drive! It's good for setting the summertime mood too!

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

Indeed .. the smoother the driving style = the less fuel used. We also find repair bills and tyre replacements are more cost effective as well by keeping things smooth and COAST -led of course

I've made it down from Durham and well into France on one tank full before now

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Take with a chuckle or a grain of salt
Drive without COAST and it's all your own fault!

A SMILE is a curve that sets everything straight (P Diller).

A Smiley Per post
FINES USfor our COAST!

Approach love and cooking with reckless abandon - but driving with a smile and a COAST calm mind.

Of course, the fact that you don't want to slow down then speed up again if you can avoid it is a good excuse to straight-line certain roundabouts without slowing down (other traffic permitting)....

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Paul Smith: a legend.

"The freedom provided by the motor vehicle is not universally applauded, however: there are those who resent the loss of state control over individual choice that the car represents. Such people rarely admit their prejudices openly; instead, they make false or exaggerated claims about the adverse effects of road transport in order to justify calls for higher taxation or restrictions on mobility." (Conservative Way Forward: Stop The War Against Drivers)

Hmmm. I guess that might depend largely on WHAT the driver was concentrating on!

I actually feel completely the opposite to be honest. I think that it's hard to drive as safely and as economically as possible simultaneously. For a start, for optimum safety in town you'd pretty much always want to be a gear lower that the one you'd select for maximum economy. Then, when trying to go for maximum economy, there is a huge temptation not to loose your momentum which can sometimes result in tailgating and / or obstructing. Maximum economy driving also provides a dis-incentive to stop at "give-way" signs...

Then, of course, there's the constant watching of the instantaneous consumption on the trip computer and the fuel gauge which, when combined with the constant attention that our mates in the scamera vans require us to pay to the speedo and the rapidly changing speed limits must leave very little time for watching the road!

Filled up yesterday and have now got the Civic up to 41.2 MPG around town doing sub 6 mile journies with the air conditioning on

This new driving style is taking alittle adjusting to, but it's coming along nicely. I think I am COASTing better/more effectivly now, but there does seem to be less traffic about which makes flowing driving much easier.

Re brakes being the most fuel using part of the vehicle... I read in BIKE I think that a sports bike brakes are 500 hp

Just because I'm not a fellow "anti camera" traveller, you don't have to automatically disagree with everything I post.

Clarkson was on about the fact that to truly drive smoothly and economically (and safely) you have to give all of your attention to the road - short distance to avoid costly harsh braking, long distance to plan your track to ensure smooth progression, behind you both short and long distance as every manouever must be planned and executed carefully so as not to incur harsh acceleration or braking. This compared to the 7% to 15% of concentration usually given to the driving task.

Anyway, Clarkson IS one of the safespeed fellow travellers, I'm only reporting what he said, Look for the clip on youtube if you don't believe me.

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

I used to be on a car forum where it was often reported that to achieve maximum MPG you would need to drive with...

Air Con Off
During the day so as to not use your headlights
and with Sound System off.

Are these things true? And if so does that mean the use of Cruise Control has a similar negative effect on MPG?

My understanding is that the Air Con will always use quite a bit more fuel. Anything else that uses power will put a load on the engine but not use a significant amount of fuel. But I wonder if it's possible that with all electronics apart from the spark plug off, the engine set up will generate and waste some power.

Also you might wanna push or hill start the car to avoid using the starter motor .

I've read on here before that opening the windows to cool down is better at low speeds, and using an air conditioner is better at higher speeds.

All electrical devices will use power, and that power comes from the fuel.

Modern cars I am told can vary the loading of the alternator (by varying the voltage on the field coil?) so, for example, when flooring it up hill the alternator will turn off.
Presumably this can also turn the alternator off/down when the battery gets near to being full?

I am thinking that a cranking handle/mechanism would only save energy if it was lighter than the starter motor. I'm not sure how true that is though.

If the government wanted us to save fuel you'd think they would tell us these tips...

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Andrew.