Efficiency of internal-combustion engine

America s roads more than tripled, General Motors overtook Ford as the world s largest carmaker. And as engineers improved the efficiency of internal combustion engines, the need for more efficient fuel became even more pressing. Adding to the car industry s pressure for a solution to the fuel problem, the U.S. Geological Survey announced—mistakenly—that world petroleum deposits would be depleted in a few years. 

Pure barium metal has few commercial uses because of it reactivity with air and water. Nevertheless, this property makes it useful as a getter or scavenger to remove the last traces of gas from vacuum tubes. Barium metal is used to form alloys with other metals. One alloy is used to make sparkplugs that easily emit electrons when heated, thus improving the efficiency of internal combustion engines. 

An Opel Zanfira powered by a 30-kW fuel cell, which was supplied with hydrogen from a methanol fuel processor, was developed by General Motors [582]. The maximum efficiency of this system amounted to 30%, which considerably exceeded the efficiency of internal combustion engines. One of the development goals was to achieve a gasoline consumption equivalent of 3 L per 100 km [583]. 

In addition to their applications in EVs, ESs can also be used to maximize the efficiency of internal combustion engines (ICEs) in hybrid vehicles (HEVs). For example, 42 V electrical systems were proposed to meet the increased power demands of luxury vehicles, and alternatives to devices such as starter motors will become viable [23]. In a 42 V vehicle, one such an... 

Figure 4.10 Direct thermoelectric generators will compete in efficiency with internal combustion engines when thermoelectric materials with figures of merit ZT of the order of 2 are available at temperatures above 900 K.

Solid-state devices based on stabilized zirconia electrolytes are of considerable significance in the energy industry. In this sense, the elevated ionic conductivity, and mechanical and chemical stabilities of zirconia have been applied in oxygen sensing, for prolonged periods, to monitor the operation of internal combustion engines in automobiles, to raise fuel efficiency and minimize emissions [186],... 

These cars have many benefits. Fuel cells have an efficiency of 50 to 60%, which is about twice as efficient as internal combustion engines. These cells are also safe for the environment because they can produce only water as a by product. Unfortunately, fuel cells are expensive because they contain expensive materials, such as platinum. 

As the efficiencies for internal combustion engines are generally calculated with respect to the lower heating value of the fuel, also for fuel cells the theoretical efficiency can be evaluated using the hydrogen s lower heating value as AH value, in this case Eq. 3.16 becomes ... 

---