Energy-efficient driving

[1] Simple things such as keeping tires properly inflated, having a vehicle well-maintained and avoiding idling can dramatically improve fuel efficiency.

While up to 95% of the efficiency limits at city speeds are intrinsic to the construction of the vehicle,[6] wide variety of techniques contribute to energy-efficient driving.

[7] Improper wheel alignment and high engine oil kinematic viscosity also reduce fuel efficiency.

Drivers can increase fuel efficiency by minimizing transported mass, i.e. the number of people or the amount of cargo, tools, and equipment carried in the vehicle.

Removing common unnecessary accessories such as roof racks, brush guards, wind deflectors (or "spoilers", when designed for downforce and not enhanced flow separation), running boards, and push bars, as well as using narrower and lower profile tires will improve fuel efficiency by reducing weight, aerodynamic drag, and rolling resistance.

At higher speeds, wind resistance plays an increasing role in reducing fuel economy in automobiles.

[14] Individual drivers can improve their fuel efficiency and that of others by avoiding roads and times where traffic slows to below 45 mph (72 km/h).

So a fuel-efficient strategy is to anticipate what is happening ahead, and drive in such a way so as to minimize acceleration and braking, and maximize coasting time.

At medium speeds, the driver has more time to choose whether to accelerate, coast or decelerate in order to maximize overall fuel efficiency.

By allowing their vehicle to slow down early and coast, they will give time for the light to turn green before they arrive, preventing energy loss from having to stop.

Due to stop and go traffic, driving during rush hours is fuel inefficient and produces more toxic fumes.

An example is Maine Revised Statutes Title 29-A, Chapter 19, §2064[21] "An operator, when traveling on a downgrade, may not coast with the gears of the vehicle in neutral".

Similarly, anticipation of road features such as traffic lights can reduce the need for excessive braking and acceleration.

Drivers should also anticipate the behaviour of pedestrians or animals in the vicinity, so they can react to a developing situation involving them appropriately.

Using air conditioning requires the generation of up to 5 hp (3.7 kW) of extra power to maintain a given speed.

[citation needed] A/C systems cycle on and off, or vary their output, as required by the occupants so they rarely run at full power continuously.

Switching off the A/C and rolling down the windows may prevent this loss of energy, though it will increase drag, so that cost savings may be less than is generally anticipated.

[25] All vehicles in the United States built since 1996 are equipped with OBD-II on-board diagnostics and most models will have knock sensors that will automatically adjust the timing if and when pinging is detected, so low octane fuel can be used in an engine designed for high octane, with some reduction in efficiency and performance.

[26] This driving strategy has been found and experienced by drivers to save fuel for a long time, and some experiments also validated its fuel-saving ability.

The pulse-and-glide strategy is proven to be an efficient control design in both car-following [26] and free-driving scenarios,[28] with up to 20% fuel saving.

This efficiently obtained kinetic energy is then used in the glide phase to overcome rolling resistance and aerodynamic drag.

Such a failure is due to signals, stop signs, and considerations for other traffic; all of these factors interfering with the pulse and glide technique.

Shifting gears and/or restarting the engine increase the time required for an avoidance maneuver that involves acceleration.

However it is also likely that an operator skilled in maximising efficiency through anticipation of other road users and traffic signals will be more aware of their surroundings and consequently safer.

Artificial intelligence (AI) and machine learning (ML) models have been applied to the relationship between fuel consumption and driving behavior.

The main factors representing and influencing driving behavior include velocity, acceleration, gear, road parameters, weather, etc.

[39] Enthusiasts known as hypermilers[3] develop and practice driving techniques to increase fuel efficiency and reduce consumption.