This article is a travel topic
Hypermiling is when the driver of a vehicle is careful to minimize the use of fuel and gain the most possible distance on a given amount of fuel. The 21st century has seen a drastic increase in fuel prices in most countries, leading many motorists to want to hypermile while driving. Hypermiling can be performed with any vehicle, regardless of its fuel efficiency, though it is easier with an automatic transmission. The typical hypermiler can realistically expect a 10-20% increase in fuel economy, though some of the most extreme hypermilers have reported getting 2-3 times the vehicle's rated level. Such extreme hypermiling is considered to be unsafe, very likely breaks traffic laws, and should be avoided.
Some hypermiling techniques increase safety; others can be dangerous and should be avoided. This article compares various hypermiling techniques that have been used and whether or not they are worthwhile.
The basic principle behind hypermiling is that you attempt to move the vehicle as much as possible without using the pedals, and minimize the gas pedal's use altogether. On a flat surface, a vehicle with automatic transmission will move at slow speeds when a foot is on neither on the gas or brakes. Fuel is also wasted during braking, because fuel has already been used to give the vehicle the momentum it needs to move a certain speed and distance, but that has been lost when the vehicle has not been moved.
Hypermiling takes a lot of alertness behind the wheel. Paying attention to every moment of your driving and not driving on mental autopilot is important.
Be patient and relax
Keep in mind that the object is not to race other vehicles on the road or to reach your destination as fast as you can, but to maximize your fuel savings. You may have to sacrifice a few extra minutes on your journey here and there. If you must arrive at your destination by a certain time, allow extra travel time for that.
Obey the speed limit
Higher speed driving uses increased amounts of fuel. Particularly if your speed exceeds 60 mph/100 kph, you are increasing the amount of fuel you use to travel a mile/kilometer. Exceeding the speed limit also increases the likelihood that a sudden stop may be required when traffic or road conditions require slower driving.
Use cruise control
Cruise control holds the vehicle at the same speed as best as it can (except when the vehicle is going down a steep hill). When driving without cruise control, and attempting to maintain a steady speed, you will find yourself driving above the speed at times and below it at others because it is hard to get the foot to stay in one position on the pedal for a long time. But cruise control can do just that for you, thereby making the best possible fuel efficiency.
Cruise control is useful when traveling along a road where frequent starting and stopping will not be necessary for a period of time, and where the speed will still the same. It should be disengaged while climbing a steep hill, since this process uses increased amounts of fuel. In most vehicles, cruise control does not work at speeds under 25 mph/40 kph.
It is unsafe to use cruise control when the ground is wet or icy.
Anticipate red and green lights
This is easier to do if you are familiar with your route. If you are approaching a light that is red, try not to come to a complete stop at the light if you know it'll soon turn green. Rather, try to slow down the car gradually, so when the light turns green, you can speed up at this point from a moving rather than a stopped position. This is not always possible, but you can increase the likelihood of this happening by knowing the patterns along a regular route.
If the light is green when you are a significant distance behind, there is a good chance it'll be red by the time you reach it. If you believe it will be red, this is a good time to quit using the gas and reach the light on momentum, using the brakes as necessary.
When a vehicle is going downhill, there is usually no reason at all to use the gas pedal. Let the gravity do the work. Use the brakes only when necessary to control the vehicle, avoid exceeding the speed limit, avoid tailgating, and for other safety issues.
Make gradual starts from a stopped position
More fuel is needed to start moving a vehicle from a stopped position due to inertia. It takes more energy (and therefore more fuel) to fight the inertia that is keeping a vehicle from accelerating to a high speed from a stopped position. It takes less such energy to increase the speed minimally. So when you slowly increase a vehicle's speed, you are reducing the amount of fuel required.
Make gradual stops
When you press on the brakes, fuel that is used for vehicle momentum already is wasted and will not accomplish any movement of the vehicle. In order to prevent this from happening, it is a good idea to take your foot off the gas pedal well in advance of a stop and let the vehicle slow down gradually.
Knowing a route is very helpful in accomplishing this. This way, you can predict the lights, traffic conditions, and other details of the patterns.
But if you have never driven somewhere before, stare ahead and try to best anticipate what is coming up.
Turn off engine while idling off roadway
You should not turn off the engine while stopped at a light (see below). But while waiting in a vehicle in a parking space for one reason or another, it is recommended that you turn off the engine. Many believe fuel can be saved by allowing a vehicle to idle rather than turning it off and restarting it. That was true with cars in the past. But today's cars use more fuel idling for just 10 seconds than when started. So if you must wait for 10 seconds of longer in a parking space, unless you badly need the AC or heat to stay comfortable, turn the engine off.
What not to do
Keep AC off in hot weather
In older vehicles, running the air conditioning would increase fuel consumption. This is not true nowadays. Modern vehicles use the same amount of fuel whether the AC is on or off. The consequences of driving with the AC off in hot weather are that the windows of the vehicle will likely be open, thereby increasing drag, and decreasing fuel economy, and that since you will be extremely hot, your alertness will be compromised, thereby reducing your concentration on the hypermiling. It is not worth suffering from the heat over a myth that you may you will save fuel.
Run red lights or stop signs to avoid making a stop
This is illegal and extremely dangerous. Even if the area where you are has little traffic, and running one will not likely result in you violating someone else's right of way, there may still be a vehicle you may not notice coming out of a spot you cannot see. And there may also be a police officer hiding somewhere waiting for the next motorist to commit such a violation.
Turn the engine off while stopped at a red light
If you turn on the engine the moment the light turns green, it'll take several seconds before you actually are able to start moving the vehicle. Meanwhile, vehicles behind you will be pressuring you to go. There will be so much pressure that you will need to slam on the gas, thereby defeating the purpose of having turned off the engine altogether.
Turn the engine off while moving
This is moderatly dangerous! When the engine is off, the vehicle lessens its ability to steer and brake, functions that are commonly needed in a split-second's notice while driving, and the reduction of the ability to use these functions could lead to an accident. Besides, modern vehicles use minimal amounts of fuel to start, so the savings is not tremendously high. It may also be noted that during the lifetime of the vehicle the extra wear on the starter can cause failure.
You win some, you lose some
Be aware that you may not always be successful when attempting these techniques. You may get better as you practice them more often, but even if you become a pro, you will never be perfect. Don't be discouraged be occasional or even regular failures. Even if you are only occasionally successful, those occasions in which you are can translate into the savings of a tank of gas over the course of several months you are not even aware of.
And remember, safety is of prime importance, and it is never worth compromising safety over a few drops of fuel. An accident will probably cost you a lot more than a tank of fuel, and could even cost you your life.