Tank to wheel

TAR tee TDM toe TPES TSA TTW IPCC Third Assessment Report Tons of coal equivalent Transport demand management Tons of oil equivalent Total primary energy supply Temperature swing adsorption Tank-to-wheel... 

Tank to wheel efficiency Flydrogen loading type - approx. 60% (LHV), approx. 51% (HHV) Gasoline loading type - approx. 48% (LHV), approx. 45% (HHV) System Power generation efficiency over 40% (HHV) total efficiency over 80% (HHV) durability over 40,000 hours... 

For fuel cell hybrid vehicles, today s vehicle (tank-to-wheel) efficiency is 50 percent, but the well-to-tank efficiency is low. Toyota has set a target of 42 percent total well-to-wheel efficiency (which is three times higher than that of current gasoline vehicles). To achieve this goal, fuel cell vehicle efficiency must be over 60 percent. Simultaneously, Toyota has also requested the energy industry to develop high-efficiency hydrogen production methods to achieve 70 percent or more well-to-tank efficiency. 

Other authors have quoted somewhat higher eificiencies, usually based on the LHV of hydrogen, and lower power outputs. For instance, the Ballard Mark 902 module is said to deliver a maximum efficiency of 48% (LHV) at partial load. This equates to 40.6% (HHV). Thermodynamically, the HHV should be used. When electrical and mechanical losses are included, the tank-to-wheels efficiency reduces to around 33%, in line with our stated range. As noted above, DaimlerChrysler claims 60% efficiency for their F 600 Hygenius car, but this figure needs clarification. 

Well-to-wheel efficiency includes both the well-to-tank efficiency, associated with the entire front end of the fuel and vehicle production, and the tank-to-wheel efficiency, the... 

The most attractive feature of the fuel cell technology is probably its superior energy efficiency as a part of a hydrogen-fuel cell-electro-motor power-train, that is, in the tank-to-wheel (TtW) part of the fuel chain. On the other hand, the energy loss in hydrogen production, that is, in the well-to-tank (WtT) part of the fuel chain, is considerable. The total well-to-wheel (WtW) efficiency is potentially superior to even advanced ICVs or hybrid solutions. 

Conventional power trains for passenger cars based on internal combustion spark or compression ignition engines (ICE), today have a tank to wheel efficiency of only 19-21% when benchmarked on standardized cycles, such as the New European Driving Cycle (NDEC) [22]. Therefore, there is a significant potential for CO2 emission reduction through efficiency increase. 

Edwards, R., Larive, J.-F., Beziat, J.-C. Well-to-wheels analysis of future automotive fuels and powertrains in the European Context. Tank-to-Wheels Report Vwsion 3c, Jul 2011. 

Furthermore, test vehicles equipped with data loggers deliver important data for development, verification and validation on public roads in the United States, Europe and Dubai. Available real-world data confirms how significtmtly the Voltec propulsion concept can replace gasoline as an energy carrier by electricity. Application of electric energy from renewable sources is reducing the tank-to-wheels (TTW) greenhouse gas emissions further substantially. 

However, for automobile applications, H2 has to be highly pressurized due to space limitations. If the overall electrolysis plus pressurization efficiency is 70% to generate 700 bars H2, and the overall fuel cell system efficiency is 40%, then the entire electrolyzer-fuel cell system can achieve a well-to-wheel electrical efficiency of aroimd 28%. This is still about twice of the tank-to-wheel efficiency achieved by conventional internal combustion engines (ICEs). 

JRC (2008) Well-to-Wheels Analysis of Future Automotive Fuels and Powertrains in the European Context. TANK-TO-WHEELS Report, Appendix... 

Concawe (2008) Tank to Wheels Report Version 3.0, http ffies.jrc.ec. europa.eufuploadsfmediafV3.1%20TTW %20Report%200710200S.pdf ( asx accessed 3 February 2012). 

In the first step, the weU to tank analysis evaluates the energy conversion from its primary source to its storage in the reservoir. The tank to wheel analysis describes the conversion from the reservoir via energy converter and torque converter to the wheel of the transport system. The well to wheel analysis combines both approaches and displays the fuU picture with regard to the relevant parameters, for example, greenhouse gas emissions, efficiency, and others. 

Figure 4.3 The gravimetric enei density (Whkg ) of various types of rechargeable battery systems compared with gasoline. In the practical Li-air battery, the value is just an estimate. For gasoline, the value includes the average tank-to-wheel efficiency of cars.

Tank-to-wheels efficiency Fuel ceU systems use less energy than conventional power trains, because of the intrinsic high efficiency of the stacks. Hydrogen-based FCVs exhibit significantly higher fuel economy than those employing on-board fuel processors. 

Well-to-tank Tank-to-wheel Well-to-wheel... 

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