# Strategies for Reducing Automobile Fuel Consumption
## 3 Vehicle Design and Technology
### Other Technologies Related to Fuel Economy  
The entire planet is linked by a massive transportation infrastructure, which is largely based on the use of the internal combustion engine (ICE). It would take decades and tremendous financial expense to replace ICEs, so it is probable that they continue to be the central powertrain technology used for road transportation all over the world in the coming years. [PERSON] [41] indicated the obstacles still faced by current alternatives to ICEs, such as _electric vehicles_ (EVs) powered by _batteries_. _Currently, electric_ batteries have high cost, weight, and other limitations. Furthermore, they are expected to be charged using energy obtained from renewable sources, such as wind and solar. Nevertheless, these sources still represent a small fraction of the world's energy supply. The reduction of fuel consumption in road transportation needs to be addressed by a mix of solutions, involving battery and hybrid electric vehicles (BEVs and HEVs), fuel cell electric vehicles (FCEVs), and conventional vehicles (ICEs), depending on the consumer, the country, and the specific application considered. Energy consumption during _fuel production and transportation_ is closely related to fuel economy. In this sense, the life cycle assessment (tank-to-wheels) is an adequate measure of fuel performance. The selection of the feedstock and the fuel production pathways have a great impact on the overall energy efficiency of road vehicles. BEVs have a higher in-use energy efficiency as compared to HEVs; BEVs can convert 70-90% of the energy stored in the battery into movement, whereas the theoretical peak efficiency of HEVs is only 40%. Some of the in-use efficiency advantages of BEVs over HEVs are offset by the conversion losses occurring during electricity generation from fossil fuels and by losses during transmission and charging. Collectively, this can add up to around 60% of the total energy use. Another factor affecting the energy efficiency of BEVs is the electricity consumption of _auxiliary systems_, like heating and air conditioning. To provide energy for A/C systems, BEVs must use energy from the battery, while HEVs can make use of waste heat from the engine. Energy consumption varies across different electric vehicle sizes, and the average BEV is heavier than the average HEV. The extra weight of BEVs, imputable to the weight of the battery and the associated secondary weight required to strengthen the vehicle body, reduces the energy advantage of EVs over HEVs in terms of energy consumption. The reduced mass of vehicle components, obtained by replacing existing materials with lighter ones, must be balanced with the energy expenses during vehicle production. On the other side, it seems that road transportation will always have some energy externalities, even if all ICEs were replaced by EVs. Although the energy efficiency of electric motors is far larger than ICEs, the energy required to produce electrical energy for EVs is far higher than that required to produce fossil fuels. Moreover, the production of batteries is an energy-demanding activity. The reduction of the mass of EVs would contribute to lower energy required per km. Additionally, the recycling of batteries is also an energetic and environmental task to be solved. _Modern control systems_, characterized by their adaptability, are important in increasing a vehicle's efficiency, especially in managing the engagement of engine cylinders. Some manufacturers have pioneered the _Cylinder on Demand_ technology, aiming to improve fuel efficiency through selective cylinder deactivation. Concurrently, _Dynamic Skip Fire_ systems have been introduced. This innovative approach intelligently deactivates distinct cylinders based on immediate operational demands, thus ensuring proficient torque delivery while maintaining optimal noise, vibration, and harshness levels (i.e., NVH levels). Such cylinder deactivation strategies introduce unprecedented versatility and precision, promoting holistic enhancements in vehicular performance.