Fuel cell vehicles efficiency

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. 

See also Batteries Capital Investment Decisions Consumption Economically Efficient Energy Choices Electricity Electric Power, Generation of Faraday, Michael Fuel Cells Fuel Cell Vehicles Magnetism and Magnets Oersted, Hans Christian Tesla, Nikola. 

The problem is that hydrogen, even at 10,000 psi (or 690 bar), requires five to ten times the volume of today s gasoline tank, depending on the fuel cell vehicle s real world efficiency. Packaging volume is compromised even further because pressurized tanks require thick carbon fiber walls and are, therefore, nonconformable. Moreover, they may cost several thousand dollars more than a conventional gasoline tank. 

See also Efficiency of Energy Use, Economic Concerns and Engines Fuel Cells Fuel Cell Vehicles Hydrogen Methanol Synthetic Fuel. 

As crude oil reserves dwindle, the marketplace will either transition to the electrifying of the transportation system (electric and fuel-cell vehicles and electric railways), with the electricity being produced by coal, natural gas, nuclear and renewables, or see the development of an industry to produce liquid fuel substitutes from coal, oil shale, and tar sands. It might also turn out to be a combination of both. The transition will vary by nation and will be dictated strongly by the fuels available, the economic and technological efficiencies of competitive systems, the relative environmental impacts of each technology, and the role government takes in the marketplace. 

As a constituent of synthesis gas, hydrogen is a precursor for ammonia, methanol, Oxo alcohols, and hydrocarbons from Fischer Tropsch processes. The direct use of hydrogen as a clean fuel for automobiles and buses is currently being evaluated compared to fuel cell vehicles that use hydrocarbon fuels which are converted through on-board reformers to a hydrogen-rich gas. Direct use of H2 provides greater efficiency and environmental benefits. ... 

In order for hydrogen fuel cell vehicles to reduce global warming gases, the electrolysis process will need to become more efficient, and the electric power will need to be produced from a higher percentage of low-to zero-carbon sources (renewables or coal with carbon capture and storage). 

Bibendum competition in Shanghai. The competition pitted 74 hybrid, diesel and fuel cell vehicles, measuring acceleration, fuel efficiency and C02 emissions. 

The timetables announced by government and industry have generally been proven too conservative. Many auto companies already have running drivable fuel cell prototypes and it appears likely that some moderate commercialization will be achieved in the next decade. Hybrids are already here and proving to be popular because of their efficiency. They are providing valuable data on the type of electric drives that would be used in hydrogen fuel cell vehicles. 

Another competitor for fuel cell vehicles could be the diesel engine. Diesel engines are used in large trucks and construction equipment for their high efficiency and durability. 

Fuel cells typically have higher efficiencies at lower power, so a hybrid fuel cell vehicle with battery will not improve its efficiency as it does for a gasoline engine. 

However, it has to be noted that, from the perspective of providing mobility, by using that natural gas as feedstock -and taking into account fuel production and vehicle conversion efficiencies - the majority of passenger cars can be fuelled with the production of liquid fuels from oil sands, followed (with about a factor of three less) by its conversion into hydrogen and subsequent use in fuel-cell vehicles, and its direct use in CNG vehicles. 

Equally, electricity can be generated from a wide variety of energy sources, and battery-electric vehicles have a far higher efficiency than fuel-cell vehicles, as the high discharge rate of the battery is almost double the efficiency of a fuel cell. Battery-electric vehicles or PHEVs are also advantageous, as they can rely on an existing supply infrastructure. 

Still, the efficiency of hydrogen fuel-cell vehicles is about twice that of current internal combustion engines on the highway, and about three times as high in urban traffic (and between 1-1.5 times more than hybrid electric vehicles (IEA, 2005)). A clear advantage of fuel cells is that at part loads, fuel-cell drives have a higher... 

Today, the power train costs of fuel-cell vehicles are still far from being competitive. They have the largest influence on the economic efficiency of hydrogen use in the transport sector and the greatest challenge is to drastically reduce fuel-cell costs from currently more than 2000/kW to less than 100/kW for passenger cars. On the other hand, fuel-cell drive systems offer totally new design opportunities for... 

---