A Simple Theory
When you press the gas pedal, you are spending money. When you hit the brakes, you are wasting money. Therefore, the obvious way to save gas is by keeping your car moving by avoiding unnecessary braking. This does not happen automatically; it takes effort to change your driving habits, but it's worth it.
Now please understand I am not saying you should not use the brakes that your automobile comes equipped with; brakes are a safety feature. But... if you can avoid using them unnecessarily, you will save money. This is indisputable. For more details on how to actually make it happen, read on. But if you stop reading now and just take that idea and apply it in any small way, you will save at least some money on your fuel bill. Oh, and if it seems silly or extreme now, come back and read this again when gas is $8, or $10 a gallon.
I was talking with my friend Helen about how we can all save gas by adjusting our driving habits. I confessed that I understand the concept, but I still have to work on actually changing the way I drive. For it to work, I have to learn to be deliberate about how I drive. She replied with such a profound statement that I have to share it with you.
She said, “In these times, we all need to try to live a lifestyle of conserving.” Smart lady. This is becoming a pervasive concept. These days, it seems everything we do is tempered by the realization that we need to prioritize, strive for efficiency and reduce waste.
She also said, “It makes sense to adjust your driving habits just as surely as you adjust your electricity use and your grocery shopping.” Again, she's right. Almost everyone is thinking about ways to reduce their power bill by hanging laundry, adjusting air conditioner settings, or whatever. You have to drive, so why not examine the way you drive?
My pickup truck used to have bad brakes. If I hit the brakes, the pedal would go to the floor with unpleasant results. So I had to drive slowly and try to keep moving. If I did have to stop, I had to give myself enough time and space to pump the brakes and stop gradually. I realized that if I drove that way all the time, I would surely save gas, but I forgot about it until gas went up to over $4.00 a gallon. It’s time to resurrect a good theory.
Truck drivers who drive the big rigs use the same idea; if you can keep moving, it is a lot easier than stopping and then starting from a dead stop. And it’s cheaper. By a lot.
Here are a few easy ways to increase your miles per gallon:
Slow down. The faster you go, the more it costs to get going and the more you waste when you use the brakes to slow or stop. The couple of minutes you may or may not gain by speeding between red lights are just not worth it. Stopping at five red lights is the same as cruising slowly through five green lights, but a lot cheaper. Better to leave five minutes early (in case you get an extra red light) and enjoy the ride. Your fellow travelers will also appreciate it.
Stay back. You may have noticed that the drivers who follow close to the car in front are constantly flashing the brake lights. If you back off to a proper—and safe—two or three seconds, you don’t have to hit your brakes every time the car in front shows brake lights. You can respond by taking your foot off the gas pedal and slowing naturally. I mean, really--there is no reason to be following close to the car ahead and hitting your brakes if you are on an open highway. Just leave a great big cushion of space around you and you can keep moving. Your roadway companions will also benefit from the added safety margin.
Anticipate. Pay attention to the traffic lights. If the light is red or about to turn yellow, there is no point in racing up to it and slamming on the brakes. If you slow down soon enough, it may turn green and you can keep moving. You save gas two ways when this happens: you don’t have to use the brakes as much, and you also don’t have to start from a dead stop. This can be mildly effective or super-effective, depending on how much effort you put into it. Other roadway users will also be safer if you avoid abrupt driving.
Use these ideas in combination for even more effective gas saving. For example, when you stay back, you increase your field of vision. This allows you to see which lane is moving so you can position yourself in the best lane. It’s kind of silly to lurch back and forth trying to go faster when you are so close to the bus in front of you that you can’t see which lane has a tractor going ten miles per hour. Staying back allows you to be more effective in anticipating which lane will be most likely to keep moving.
Driving a bit slower allows you to back off and increase your vision so you can more effectively anticipate and adjust for other drivers, traffic lights, and things like closed lanes. It all works together.
Practice identifying the aggressive and erratic drivers. These guys will lunge in front of you and take away your safe following distance. If you see them coming early, you can be ready for it and maintain your space cushion, which is what allows you to keep moving.
OK, so maybe this is obvious. But it does work. When you are serious about actually saving gas instead of lamenting, all you have to do is change your habits. That's the hard part. I am actually doing this, but sometimes I forget. It only works when you are deliberate about it. I read somewhere that it takes 21 days to create or break a habit.
My recommendation: make it a game. Enlist the help of your passengers to remind you. Assign points--five points for a smooth stop, ten points if you manage to keep going by slowing down early. Watch for other drivers who speed up to red lights and jam on the brakes. Remind yourself how silly that looks. Assign them penalty points.
If you make it a game, it helps to keep your mind engaged in the task of driving. And if you are deliberate about your driving, you will be successful at saving gas. Soon you will have made it a habit and it will be easier. Then you will wonder how you ever thought it was appropriate to drive so abruptly in the first place.
I have been teaching this to new drivers and they will definitely benefit from learning it early. They will have a habit of driving to save from the beginning. Then they don't have to change bad habits. I also point out that the $60 they pay for the driving lesson can be recovered in a couple of months of smooth driving. A free driving lesson!
I invite you to notice that all the practices I have recommended above have the additional benefit of increased safety, calmness and respect for others. Times are tough. We don’t need to make it worse by hating and hurting each other on the road. If we gradually change our collective driving habits, there will be excellent side effects.
To save gas and stress, try to keep moving. Drive like your brakes are bad and you cannot make sudden stops. It takes conscious effort to make it a habit.
Smooth out your driving by slowing down a bit and backing off a bit. Pay attention to the road and be deliberate about anticipating things that will make you slow down or stop, especially traffic lights. If you know you will have to stop, slow down early and let friction do its thing. Realize that cruising slowly through 5 green lights takes the same amount of time as speeding up and then braking at 5 red lights. Exactly the same.
Look ahead and respond early to developing situations. Take your foot off the gas pedal as soon as you see anything suspicious, such as cars merging ahead or brake lights flashing. Pay attention to the driving style of the other drivers. Identify and avoid erratic drivers. Watch and learn from the guys who drive the big rigs.
Leave five minutes earlier and enjoy the ride. The reduced anxiety and increased safety will benefit everyone.
I used to drive the church van. I would go to church, pick up the van and then pick up all the people and take them to church. After church, I delivered them home and brought the van back to church. This was a big seventeen-passenger van with an old flatulent engine. My Sunday drive was costing $15 in gas. The church paid for it, but I wanted to do better, so I tried to adjust my driving to see if it would have any effect.
I was surprised to find that when I made a deliberate attempt to watch my driving (slower acceleration and smoother stops), I burned $9 in gas. That’s right—in one day I saved $6 worth of gas. And I continued this strategy for week after week with the same results. It was really effective.
Now, I don’t drive a gigantic vehicle and I don’t drive that much every day, but even with my modest Corolla I know I am doing better. You can, too.
The Physics- Just for Fun- And Why it Works
It costs money to create momentum. When you hit the brakes, you are converting that movement into useless heat energy which is dissipated off the brake pads into the surrounding air.
Remember that energy is conserved; none is lost or gained, but it changes forms. Energy tends to convert from useful and available forms to disorganized and unavailable forms (Second Law of Thermodynamics). Here is a partial explanation of physical events that occur when you accelerate and then brake:
Gasoline is a fossil fuel. The thermal energy from the sun helped the organic matter to grow and other physical forces caused it to turn into the oil that gasoline is manufactured from. Because of its molecular structure, gasoline contains potential energy.
You put that gas into your car and when you hit the gas pedal, the gas is injected into the the cylinders of the engine and it burns up in controlled explosions. The energy stored in the gasoline is converted to heat energy (thermal energy) and when it explodes in the cylinder, it pushes the pistons. This converts the heat of the explosion into the downward motion of the piston. The gasoline started as stored energy. Then you turned it into heat energy (burning it in the cylinder), and now it has become kinetic energy, the energy of motion.
A series of machines take that piston movement and convert it into spinning and twisting motions through the crankshaft to the transmission, the drive shaft to the axles, and on to the wheels.
The wheels spin. Because the car is held to the ground by gravity, there is friction so the tires do not really spin right away; instead, they push against the road and convert the energy of the wheels to forward motion. Of course, first the inertia of the car must be overcome, so if the car is standing still, this takes extra energy. (Remember an object at rest tends to stay at rest unless acted upon by an outside force.)
Now the car is moving. When you hit the brakes, the brake pads clench the spinning disc. The intense friction causes the disc to stop spinning and your car stops. What happens to the energy you put into the system by burning that gas in the cylinder? The brake pads have absorbed the thermal energy of the friction. Now the brake pads cool down and the air around them becomes a tiny bit hotter.
You have converted ancient insolation (the rays of the sun hitting the earth) into useless heat energy which nobody can ever use again. The air and the road surface will absorb it.
When you drive, friction is always working against you. The reason you have to keep pushing the gas pedal even on a level road is that friction is always taking away the motion energy of your car. So you might as well let friction do its job and slow your car down for you instead of hitting the brakes.
One Last Word and a Warning
I am not suggesting you don’t use your brakes. I always teach student drivers to drive defensively by covering the brake. After all, how can you stop if your foot is on the gas pedal?
Also, sometimes you will be successful at getting a green light by slowing down as you approach a red light. All the cars in the other lanes are stopped (because they raced up to the red light and slammed on their brakes, Duh.) and you get to sail right past them into the intersection. YAY!
WATCH OUT! At this moment, you are in great danger. The other drivers who are stopped have the ability to look and be sure there are no cars entering the intersection. They have been sitting there and know what’s going on there. You have not been sitting there. You don’t know who is approaching the intersection from other roads. Your green light is not a guarantee of safety! Please slow down and take a look as you approach and enter the intersection. You know that dangerous drivers who purposefully go through red lights do not care who they kill and they certainly do not slow down to go through the red light.
Please approach all intersections with caution, and most especially when you have a fresh green light and you are going full speed into an intersection you have not scanned.