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| The place that hypermilers try to avoid visiting. |
While most drivers won’t necessarily be that obsessive about their mileage, there can be few that aren’t concerned about the ever increasing prices at the pumps. So these hypermiling tips can apply to everyone, but with one important caveat: a few of the practices may be downright stupid, dangerous or both.
1. Choose the right vehicle
An obvious place to start, although hypermiling skills can be applied to anything with an engine. That said, a single person who’s desperate to reduce their fuel costs would be unwise to buy something like a Chrysler Grand Voyager.
It’s all about choosing the right vehicle for the task, and then specifying the best engine and gearbox combination. Usually, that would mean going for a manual instead of automatic transmission, but in some applications the economy gap between the two has narrowed to almost nothing.
2. Drive less
This applies particularly to short runs, as these don’t give the engine time to warm up sufficiently and will probably involve lots of stop / start driving. Both factors can decimate fuel economy.
For longer journeys, the trick is efficient route planning that minimises the distance travelled while avoiding potential congestion areas.
3. Turn off the engine
Sitting in stationary traffic with the engine running is akin to burning money, so switching it off is an easy way to save cash. Better still, choose a car with an automatic stop / start system, or avoid the problem in the first place by driving at quieter times of the day.
Some avid hypermilers will advocate ‘engine off’ when going downhill, but that can create all sorts of problems. For starters, the lack of power assistance means the steering and brakes will suddenly feel much heavier to use, and there’s a real risk that on a bend the steering lock might engage. The resulting accident won’t be easy to explain to either the police or insurance company, so definitely not recommended.
4. Don’t accelerate
Of course drivers have to accelerate, otherwise they wouldn’t get anywhere. The point is that in order to reduce fuel consumption, it should be done as gently as possible while selecting a higher gear at the earliest opportunity.
Wearing very thin-soled shoes can help with this, as their extra sensitivity gives a better feel for how hard the accelerator pedal is being pressed.
5. Don’t brake
The reason why an increasing number of manufacturers are fitting brake energy recovery systems is because it’s a wasteful activity. Fortunately, it’s also one that can be often avoided with a large dose of smoothness and anticipation.
The secret is to read the road and traffic conditions so that engine braking, aerodynamic drag and friction between the tyres and tarmac alone are used to slow down. Leaving a big gap to the vehicle in front makes this much easier.
A common misconception is that when coasting with the engine on, it helps to select neutral. For the majority of modern fuel injected, ECU-equipped cars, doing that will actually use more fuel, so it’s best to keep an appropriate gear engaged.
Another basic aim is to never come to a complete stop, because that then necessitates a whole load of acceleration to get going again. For some extreme hypermilers, ignoring stop signs is fair game, but that’s something that falls firmly in the ‘unsafe and illegal’ category and so is not worth trying.
6. Stick to the speed limit
Or indeed lower, because it stands to reason that the faster a vehicle is travelling, the more fuel it’s burning. Cruise control is a useful feature to use, as it maintains an optimal throttle opening and prevents speed creep.
However, chugging along at 20 mph below the limit while holding up a huge queue of traffic is really, really annoying.
7. Lose weight
Hauling around the junk that can accumulate over time in the boot of a car costs money, so it pays to get rid of it. For some, even the spare wheel has to go, although that does become an issue in the event of a puncture.
It’s the same story with people. Giving passengers a ride will chip away at economy figures, so being anti-social can have its benefits. Of course, the flip side to that argument is that if three people can be found to car share with, then fuel costs could be split four ways.
Okay, doing that means the hypermiler’s basic ambition of achieving the best possible miles per gallon is unlikely to be accomplished. But it’ll save a huge amount of cash, which surely has to be even better?
8. Inflate those tyres
Under-inflation is a sure way to use more fuel than is necessary, so a basic task for aspiring hypermilers is to regularly check that their tyres are pumped up to the correct pressures as per the vehicle’s handbook.
There are those who go further by running on significantly over-inflated rubber. The logic behind such a tactic is that with more air inside, the contact patch between tyre and road is reduced, thereby decreasing rolling resistance.
However, that idea has two serious flaws. Firstly, less contact means less grip, which will be dangerous, especially in the wet. Secondly, it puts additional strain on the tyre’s carcass, which leads to a greater chance of having a blow-out. So for those reasons, over-inflation can’t be recommended.
9. Get aerodynamic
Wind resistance is significantly reduced by removing things like roof racks and cycle carriers when they’re not needed. Similarly, open windows at anything above low speeds increase drag, therefore they should be kept wound up.
One controversial manoeuvre employed by some hypermilers is drafting, where they’ll sit very close to the rear of something big like a truck. Being there in the slipstream effectively gives them an aerodynamic tow, and consequently their engine doesn’t have to work as hard.
Yes, it’s basically tailgating, which irritates people and is foolish. Plus, the chances are it’s all going to go horribly wrong very quickly when the truck being followed jams on the brakes.
10. Get warm
It’s estimated that using air conditioning can lead to a hefty 10% increase in fuel consumption, which means committed hypermilers will rarely - if ever - have it on.
For those who don’t want the full mobile sauna experience, using the recirculation feature or just turning it off altogether every so often should still make a difference.
Related post:
Top 10: Efficient petrol cars
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