Is there really such a thing as efficient driving? Emphatically, yes, there is. And with gas prices significantly above four dollars per gallon, and rising, you need to know about efficient driving. What is the difference between efficient and inefficient driving? At least a 30% difference in miles per gallon (mpg) is the industry accepted figure. And the figure can be much higher depending on the level of rigor that you apply to your efficient driving (and just how inefficient your driving was in the first place). With gas at 4 dollars per gallon a 30% increase in miles per gallon is equivalent to a $1.20 reduction in the price of your gas. Who wouldn't want that type of saving? Read on to find out how you can achieve that, and more.
As always, knowledge is power. To achieve your gas saving, you will need to have an appreciation of the operation of your engine. Not a particularly detailed understanding, just the basics, but this will help you drive more economically. Surprisingly, many motorists do not know or want to know even the most basic facts about their cars. And unsurprisingly, the motor and oil industries do not want to disrupt this ignorance. If consumers do not appreciate the detailed operation of the products and services they buy it is considerably easier to increase prices and charge a premium for simple products. Accordingly, car manuals are impenetrable and oil companies like to convey the impression that gas formulation is an enormously scientific subject only to be contemplated by white coated scientists. Much of the value of a car purchase is in its servicing and maintenance after purchase and the motor and oil companies want to maximize their profit after you have driven away from the lot with your new car.
With that preamble lets try to remove a little of the cultivated ignorance about the operation of your car. (Just a little, don't worry!) Essentially an engine operates by mixing gas and air and creating a sequence of explosions from the resulting mixture and harnessing mechanical energy released by the exploding gases. This is achieved in the cylinders of your engine. Each cylinder operates as a controlled gas and air mixing, compressing, and exploding vessel. The explosion transfers energy to the piston and from there the energy goes to the transmission and wheels of your car. The important aspect to appreciate is that the volume of the cylinder is fixed. To a good approximation, each cycle within the cylinder consumes the same amount of gas, so your gas consumption, to a first approximation is proportional to the engine's revolutions. So, to drive economically you need to keep your revolutions (revs) as low as possible. What does this mean in terms of your driving? Well, generally it means accelerate very slowly, keep the revs down. Change up in the gears (if you are driving a manual transmission as early as possible). You won't have a racy drive to work; but you will reduce the amount of gas and cash which is burned in the process.
That covers getting and keeping your car in motion. The next thing to know about and appreciate is stopping. There are two ways to slow a car. 'Engine braking' in which you use the engine to slow the car and the car's braking system. From the point of view of fuel efficiency both are bad! When you slow the car down using either the engine or the brakes you are converting the motion of the car (which cost you gas to obtain) into heat; so ideally you want to minimize all forms of braking. Obviously you cannot stop braking entirely, but you will want to be economical, so brake gently and if possible use general friction rather than braking to slow the car down. Ideally, you should coast to a stop - not using the brakes or engine braking - but the safety aficionados often frown on this practice because it inhibits your ability to speed away from trouble should the need arise and it isn't easy to be constantly shifting your car in and out of neutral in busy driving situations. (It will save you gas, though).
So, accelerating and braking then are best carried out in moderation, as though there is an egg between your foot and the pedal, as no doubt your father mentioned when you were learning to drive. Your father was quite correct; the benefits in terms of fuel consumption are substantial. There are additional benefits. You will find that your tires, clutch, brakes and transmission all last longer when you drive in the smooth manner advocated by the egg metaphor.
In addition to driving smoothly, and knowing the underlying reason for doing so, there are some additional simple steps which can significantly improve your fuel economy. Remove excess weight from your car. If you have a bag of cement left over from an old building project in the trunk or even a few additional boxes of car supplies you are paying to accelerate and decelerate them from place to place in additional gas consumption. Remove the excess baggage and you will see your fuel economy improve.
Similarly, if you use heavy duty electrical equipment, such as the air conditioning and deicer, be prepared to pay a cost in terms of reduced fuel economy. Make sure that you inflate your tires to the correct pressure because under inflated tires increase the drag that your engine needs to work against to move you forward.
There you have it. No racing starts, no precipitous stops, gentle acceleration and deceleration, no excess baggage, correctly inflated tires, and sensible use of your electrical accessories. These can be worth well over a dollar per gallon to you in increased fuel economy. Not only will you be helping your bank balance by learning and applying these techniques you will be helping your country with its balance of payments and you will be helping the planet too. Happy, economical, driving to you!