Save cash on fuel

EDITED – See end of text for latest figures!

Since getting my old Audi A4 (1996 Saloon) I have covered over 6000 miles in under 3 months.

I drive over 100 miles a day – and that works out as an average of 76.1 miles a day including my none driving days!

That also works out at £8.04 a day on average…. and 659.8 miles per fill up.

So… I have the perfect chance to try several ways to save fuel.

I didn’t want to do anything over the top. I wanted to make slight changes to see what would happen. The type of changes you could do quite easily without altering your driving style so much.

Firstly I did a few journeys at my normal style. I’m no racer – I keep up with the traffic and drive as the traffic around me drives – so pretty average.

The table below shows a few statistics on my trips. I purchased the car with 113816 miles on the clock – so that is why the first line shows 0mpg – I hadn’t got anything to judge it against.

By the 27/08/09 I had covered 638 miles filling up with 57.63 litres – I had covered those 638 miles at 50.33mpg – a good starting point, as when I chose the car I was looking for 50mpg or more at the very least.

The next entry and I only got 47.03mpg! I knew why though. I was a bit heavier on the throttle and harder on the brakes. I even went around a track which gave the impact of driving the car like a “boy racer” – although that was only for 3 miles…. ONLY 3 miles like an idiot racer and it hammered my economy.

The following fill up gave me 55.66mph – and that was by far gentler driving… but nothing major!

I still drove at the same speeds on the roads as I had done on the previous tests, but this time I didn’t floor the throttle to get to those speeds, and I didn’t use harsh braking to slow down.

I simply put enough throttle down to get the car moving, then as it gathered speed I’d change up a gear – but a little earlier than usual. The time it took to get up to my usual top speeds was a little slower, but it was there that most of the fuel savings took place.

When it came to driving I simply left a bigger gap between me and the car ahead. If I saw the cars ahead start to slow I would come off of the throttle straight away instead of catching up and having to brake.

This way I wasn’t wasting fuel by braking and accelerating all the time – I was just using the throttle to keep me gently at my cruising speed – which was the same cruising speed I had used from the beginning of the test.

As you can see – between harsh driving and gentle driving I had a change in mpg of 8.63 mpg… or 299 miles per tank – at the time that was £6.84 per tank saved. For me that is over £350 a year… which  covers MoT & Tax.

The thing is, the journey to and from work is not taking any longer. Just driving calmly, pre-empting what other cars were doing, having a feather weight foot rather than a lead one… it all added up.

I use the iPhone App – Road Trip to measure all of this. Since using it I have taken a greater interest in my economy – I even have all my expenses set up on it so I can see the true daily cost of my car once insurance, fuel, tax, MoT, services etc are taken into account. Currently it costs £12.21 a day – which is less than half the price of a return train ticket for my work!

Annoyingly the M3 then had months of road works – and the reduced speed took the car out of an economic cruise, so I lost the high mileage economy for a while. Still, I managed to keep the average up over 50mpg.

Yellow: Price per Litre / White: MPG / Blue: Average

I am now trying to hone my driving style to reduce the fuel cost even more. I mentioned that I would simply come off of the throttle if I was catching up with traffic. If I caught up too fast (nothing dangerous)  then I was using the brake. This isn’t the best way to save fuel…. You see modern cars that are aiming at giving better economy are now using engine braking to help save fuel. One way you can do this with older cars is to come off of the throttle, put the clutch in so the revs drop off, then slowly let the clutch out again. The speed of the car will then try to spin the engine revs back up again, and as this happens the energy used to spin the engine up is lost in speed. I am finding I can slow down quite smoothly this way – and in fact don’t need to use the brake unless I am coming to a dead stop, or if there is an event that requires faster stopping.

I also don’t sit on the clutch at traffic lights or on hills. I go into neutral and put the hand brake on. It doesn’t seem like much, but it all adds up. Correctly servicing the car, keeping the tyres to the correct pressure (an important safety check in its own right) – it’s all important in the fight to save fuel bills – and none of it is difficult to achieve.

It’s all about being calm – and it is true to a point, driving faster doesn’t get you there any quicker – but driving there with a bit more thought will save a lot of money.

UPDATE!

Even though I spent some time stuck in traffic due to a huge problem on the M27, the results from clutch braking are showing through. I have just returned my best MPG to date at 56.18mpg – giving my daily running cost (including all bills etc) of just over 15 pence!). If I carried on driving hard, that would go up to £1.15!!! That’s a heck of a difference.

One person pointed out that this may wear the clutch out more… BUT… I am using less brakes and less fuel – which more than makes up for any additional clutch wear. Also. the clutch is gently slipping within a small speed & rev range, so the wear is much less than you would get when changing gear. So clutch wear is a mute point here.

Eco Less-Unfriendly Cars

Jumping on the electric bandwagon….

I love cars. I am a petrol head and love big gas guzzling motors and the sounds they give off…. but I also like the idea of greener vehicles. We are seeing some high performance green vehicles now, so I’m not worried about all new eco-cars being slow city-cars. I’ll miss the sound and look of a V8 engine – but at least the performance will still be available in “eco” cars, where as a while a go that was not an option.

Being a throbbing engine with great sounds isn’t all important in a car really – The performance that comes from it is the important thing – the rest is just window dressing.

For performance the electric motor is like an on switch – Internal combustion won’t stand up to what electricity offers. No matter how fast you are going, you can pretty much put your foot down and accelerate as quickly from 30mph to 60mph or 70mph to 100mph  as you did 0mph to 30mph.

Electrical power is evenly distributed – there is no power band compared to a petrol or diesel engine. Sure… a chromed up V8 looks and sounds great and raw, but there are better performance options.

What gets me is the question of “Why are we trying to develop so many different alternate fuels for cars now?”

Too many choices – we’ll end up with so many different cars and a poor infrastructure to support them all. We should settle on one energy and then we can concentrate on.

With one common charge type the the only issue would be where the electricity is produced from. I don’t mean one common electric engine – I mean a common fuel and filling procedure – like we have so many petrol engines, but they all fill up the same way on the same fuel. Some motors may be faster, more economical, higher torque etc… but they are all fuelled and filled the same way. It would be easier to make  supporting infrastructure of “petrol” stations that way.

Before anyone moans about the fact that the power stations to give us the electricity aren’t very green, then I’d point you at the fact that a petrol engine is only about 30% efficient – and diesel is only about 45%. Yeah, big deal if it can do 75mpg… it’s still only 30% efficient, and as such it is still wasting energy. Add to that the wastage and energy used to drill, transport and refine that oil and that is a real waste of resources.

Real “eco-friendliness” should be measured from cradle to grave. From the moment the oil is found to the moment it goes in the car – the production process of the car, the energy used to make the car and refine the components… etc…THAT’S how to measure it.

Due to the very nature of the electric motor they have less moving parts and have higher efficiency – and the more horsepower they put out, the more efficient they are! over 125bhp and a NEME electric motor is over 90% efficient! The electric motor can get more out of the energy provided – at least twice as much more.

The motors are available NOW – so we could switch over… and yes, the ways we produce the electricity still need to be improved, but that’s no big deal because however we produce the electricity, the cars will be able to take it and operate.

As power stations improve – natural energy, solar, wind, wave – whatever – then the already efficient electric cars will get even more efficient (cradle to grave). However the electricity is supplied or produced, the cars would already be on the road to take that electricity.

Changing the way the electricity is produced won’t effect the car – but having different “eco-fuels” in development is pretty much a waste of effort and future resources that would be better spent on figuring out better ways to produce the electricity at the root – at the power stations.

As the motors develop we can even replace the petrol engines in cars that are already on the road. That’s a pretty green option as it wouldn’t need a new car to be built! Brabus has added their touch to the Tesla by adding a sound track! Check it out here! If the Brabus sound track is any good you could have your ’67 Mustang with an electric motor that gives a higher performance than the petrol V8, but still sounds as good!

World travel might be an issue with the different voltage levels – but the cars could be built with adapters and changers to accept whatever is plugged into them. It’s no problem.

Batteries and power storage is the problem at the moment – but people like Tesla are getting around it, so even that isn’t such a problem anymore.

Motor racing is helping out now as well. In Formula 1 there is a kinetic braking system (KERS) that uses braking energy and turns it back into propulsive energy. We need motor sports and recreation to keep pushing and developing these things. Cutting down on motor activities will just take the pressure off of the industries to give us the greener ways!

Remember though, and this was pointed out to me by the great Robert Llewellyn – no car can be called “Eco Friendly“, simply because the act of building one and the infrastructure to support it will effect the environment – BUT we can build “Eco Less-Unfriendly” cars.

For a petrol head, I’m actually looking forward to an electric future.