In the 21st century, the fear of pollution and the cost of fuel are on the rise.
Since the transportation industry is responsible for 30.9% of carbon dioxide emissions and 55% of world energy consumption. The world population is looking to the automotive manufacturers for a cleaner, cheaper, alternative fuel. The most promising is the electricity. As engineers struggle to develop electric cars to a more practical standard, they have come up with several different “flavors” of electric cars. The two most promising are Fuel Cell Electric Vehicles (FEV) and Battery Electric Vehicles (BEV). However, without the infrastructure in place for refilling Fuel Cells, the most realistic future is in Battery Electric Vehicles.
Technologies
At first glance both FEV and BEV technologies function the same way, by turning electric energy into kinetic energy and vice versa. Electricity is sent to an electric motor which turns the wheels, driving the car forward or backward. Electric motors give both technologies the benefit of instant torque and zero emissions. Both technologies also incorporate regenerative braking which uses individual generators at the brakes to turn the vehicles kinetic energy back into electricity. Compared to conventional gasoline powered cars, FEV’s and BEV’s are much more efficient when it comes to operational costs. It is estimated that electric vehicles cost nearly 2 cents per mile while conventional gasoline powered cars cost around 12 cents per mile indicating an extra 10 cents per mile needed in running a gasoline powered car (Wilberforce et al., 2017, Page 2, Para 4). Although electric vehicles are more efficient operationally, there are many obstacles engineers have to face to make them practical. The biggest obstacle automotive engineers face with, is any electric vehicle is fuel storage. This is also the biggest difference between Fuel Cell Electric Vehicles and Battery Electric Vehicles.
The technology between Fuel Cell Electric Vehicles (FEV) and Battery Electric Vehicles (BEV) is in the number of moving parts.
The FEV has only one moving part - the motor, while the BEV has several hundreds of moving parts. The few moving parts in the FEV bring about another major difference in the functioning and effectiveness. The FEV vehicle is not in constant need of regular maintenance and it remains more reliable than the BEV (Chau, 2014; Wilberforce et al., 2017). The BEV is in constant need of a wide variety of maintenance services such as frequent oil changes, periodic tune ups, filter replacements, and exhaust system repairs. There are also other repairs that are rare such as component replacement including restoration of water pump, fuel pump, and alternator among others.
The advantage of either FEV or BEV may be determined by the distance either vehicle can travel using a single battery.
In this argument, the electric vehicles may be limited in this case considering that they can travel for a short range on a single battery charge (Knovel, 2009). In this case, shorter distances are covered quite well by electric cars as compared to longer trips. In this Case, a lengthy period of recharging is needed for a longer period. Some vehicles allow battery swapping, but this is a recent technology that Tesla is currently pursuing. Batteries are still quite expensive and heavy and this endeavor may be difficult to pursue (Wilberforce et al., 2017).
Storage Capacities
Fuel Cell Electric Vehicles stores fuel by using compressed hydrogen. The compressed hydrogen is stored in a tank for later use, similar to the way gas is stored in conventional gasoline powered cars. The hydrogen is transformed into electricity using a Fuel Cell. The fuel cell only produces three things, electricity, heat, and water, none of which are harmful to our environment. This process is explained in greater detail by Sadiq Al-Baghdadi’s article: Proton exchange membrane fuel cells modeling: A review of the last ten years results of the Fuel Cell Research. Battery Electric Vehicles on the other hand are a little simpler. BEV’s Use a large battery to store its electricity. Like a fork in the road, these two energy storage strategies go in different directions from there on out.
Another issue in regards to the technology of both FEV’s and BEV’s is on the storage capacity which placed the hydrogen using vehicles in a compromising situation.
According to Knovel (2009), compressed hydrogen tanks take up a lot of space than a gasoline tank. The only advantage is that the compressed hydrogen tanks are not as large as the batteries and the whole of the fuel system. Thus, the hydrogen system is equipped with an inherent benefit in terms of basic energy density. The problem is that such an advantage comes with a large amount of weight. Even the components that make up the vehicle are heavier so as to control the functioning of the automotive machines (Chau, 2014). Thus, BEV’s needs a lot of energy per distance consumed as compared to FEV’s.
Costs
In modern American society people now have a surplus of gas stations and highways to choose from allowing the average American to commute to work. According to a poll taken by Princeton on Aug. 13-16, 2007, 85% of adults employed full or part-time, said they generally drive themselves to work (Carroll, 2007, para 3). The benefit of Electric vehicles is to take commuters to and from work at less cost financially and less cost to the environment.Hydrogen can be pumped into FEV’s similar to gasoline vehicles. This offers a convenient and fast way of refueling similar to what the average American is already accustomed to. BEV’s on the other hand take many hours for a full charge and even then, older battery technology can only travel and average distance of 30-50 miles. Of course, this is not the case with BEV’s like the Tesla Roadster, which utilizes the new lithium-cobalt batteries and can travel up to 244 miles. Although with a price of $109,000 the average commuter will probably not be purchasing this anytime soon. While this may seem like a clear win for FEV’s, according to the US Department of Energy’s website, there are only 39 hydrogen fueling stations in the entire US. BEV’s however can be plugged in and recharged anywhere there is electricity. The infrastructure for BEV’s is already in place.
Environmental Protection
The idea of the source of fuel brings to question the validity of the source of fuel. BEV’s are a promising alternative because they do not directly burn fossil fuels and are capable of producing smoother acceleration and instant torque. However, Wilberforce and colleagues (2017) question the environmental impact of BEV’s by confirming that sometimes the electricity used in charging the vehicle is obtained from a coal power plant. If this is the case, then the source of energy is dirtier than the internal combustion evident in the BEV. The same way of thinking may be used to determine the environmental impact of FEV’s.
Unlike electric cars, fuel cell vehicles do not experience the same limitation as those that are battery-powered.
Fuel cell vehicles can store more hydrogen fuel and this makes them more efficient. However, the lack of sufficient infrastructure that allows refueling with hydrogen prevents the development and use of hydrogen fuel cell vehicles. Additionally, hydrogen is not considered as an energy source but a carrier of power (Knovel, 2009). As a form of storage, it is not as efficient as other sources of energy such as fuel or the sun. A common catalyst of fuel cells is platinum but it is highly costly and this also produces a certain level of limitation that prevents the development and use of either vehicles.
Another aspect regarding hydrogen that questions the authenticity of FEV’s is that the gas is not a renewable source of energy and thus it does not make sense to have it as a source of power.
Hydrogen may only be considered renewable when extracted using the hydrolysis of water. High voltage electricity is needed for this procedure to occur successfully, and sometimes coal is needed to augment the abilities of conventional electricity (Knovel, 2009; Wilberforce et al., 2017). In this case, hydrogen as a source of energy is not a better option considering that there is burning of coal and the fact that only pure water must be used in hydrolysis. Unless there is a way of using wind power to produce hydrogen, then FEV’s may not be a suitable option.
Conclusion
There is heavy debate amongst the professional community as to which form of electric car technology will prevail. Although FEV technology has its benefits, the lack of infrastructure in the U.S. for hydrogen refueling is discouraging. With the vast improvements in battery technology like the one used by Tesla, it is just a matter of time until the battery is affordable to the average consumer. There are certain conclusions that remain unanswered in terms of BEV’s and FEV’s. In terms of the car size and driving cycle, BEV’s have the advantage of a lower energy consumption, but at an extremely high cost. The small BEV’s are in a position to compete with the cost of electric fuels. As a result, the option is quite good when the driving range is short. An analysis of the total energy demand place BEV’s at a better advantage. However, a variety of electric fuels come with specific pros and cons. Electric fuel may be free of toxins and pollutants thus somehow beneficial to the environment.
References
Carroll, J. (2007, August 24). Workers' Average Commute Round-Trip Is 46 Minutes in a Typical Day; Commute to and from work is not stressful for most workers. Gallup Poll News Service. Retrieved from http://link.galegroup.com.bakerezproxy.palnet.info/apps/doc/A168891522/GRGM?u=lom_falconbaker"sid=GRGM"xid=4264efe8
Chau, K. T. (2014). “21 - Pure electric vehicles”. In: Folkson, R. Alternative Fuels and Advanced Vehicle Technologies for Improved Environmental Performance. Chicago: Woodhead Publishing, 2014, pp. 655 –684.
Hydrogen Fueling Station Locations. (n.d.). Retrieved from https://www.afdc.energy.gov/fuels/hydrogen_locations.html
Knovel, S. A. (2009). Transportation in a climate-constrained world. Cambridge, Mass: MIT Press.
Sadiq Al-Baghdadi, M. A. (2017). Proton exchange membrane fuel cells modeling: A review of the last ten years results of the Fuel Cell Research Center-IEEF. International Journal Of Energy " Environment, 8(1), 1-28.
Wilberforce, T., El-Hassan, Z., Khatib, F., Makky, A. A., Baroutaji, A., Carton, J. G., "Olabi, A. G. (2017). Developments of electric cars and fuel cell hydrogen electric cars. International Journal of Hydrogen Energy, 42(40), 25695-25734. doi:10.1016/j.ijhydene.2017.07.054
