This final section of the website will discuss in more depth the two main challenges to implementing a Hydrogen economy- The storage system on board the vehicle and the infrastructure that needs to be implemented. It ends with a conclusion about fuel cells and internal combustion engines.
Challenge: Storage
One of the biggest challenges for proponents for hydrogen energy is how difficult it is to store an adequate amount of hydrogen to power a car. "In order to be competitive with ICE vehicles, fuel cells must have a similar driving range. However, because of hydrogens low volumetric density, storing enough hydrogen on board remains a challenge in terms of weight, volume, kinetics, safety, and cost. 5 kg of hydrogen is equivalent to 5 gallons (or 22 litres) of petrol, but to store it under ambient conditions would require a 5 metre diameter vessel which is impractical. [1] |
The following are different methods to store hydrogen onboard
- Liquid Hydrogen- Liquid Hydrogen has a high energy density, but comes with a serious trade off. To keep hydrogen liquified, it must be kept colder than -253 degrees celsius, which requires a lot of energy. "A quarter of the chemical energy of hydrogen itself is consumed in the liquefaction process" [1], therefore lowering efficiency. This is what BMW's has done heavy research on with cryo-compressed storage.
- Compressed Hydrogen- One of the most popular methods currently of hydrogen production because it is simple and cost effective. These store hydrogen at 350 or 700 bar and is currently the method employed by Mercedes in their F-Cell.
- Metal Hydrides- Weight is the main issue in the storage method using metal hydrides. It also takes a long time to refill the tank at a refilling station, making it very unlikely to be used to vehicles.
Challenge: Infrastructure & Delivery"The lack of a hydrogen infrastructure, which is signified in some futuristic plans as the 'hydrogen highway', is a major hurdle to the development of HFCVs." [2] (and H2ICEs)
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Recent R&D
“The fuel cell vehicle.... is seen by many as the ultimate solution to the increasing energy security and environmental problems that are confronting the road transport sector." [4]
The light blue line in figure 3 represents fuel cells and has constantly had more patents granted in every year from 2002-2012 compared to solar, wind, and the other forms or alternative energy. This shows that the fuel cell sector is constantly growing and expanding. "44% of the patents in the fuel cell sector between 2002 and 2012 went to developers from the United States, followed by 33% in Japan, 7% in Korea, and 6% in Germany; with General Motors, Honda, Toyota, Samsung, and UTC Power securing more than 60% of these patents, in that order." [3] |
Conclusions on Fuel Cells & H2ICE's
IBMW is thinking that the H2ICE can act as a bridging technology that will help deliver the world from a petrol-based energy to a hydrogen-based energy. However, it is going to take tens of billions of dollars and many years to implement a hydrogen infrastructure. The bi-fuel ability of the internal combustion engine allows the driver to easily switch to gasoline if no refueling stations are present. Also, BMW believes that their customers are people who still want a car that performs and sounds like a powerful vehicle. BMW builds cars for people who enjoy driving cars and the company kept that in mind while developing the Hydrogen 7.
However, It is obvious, based mainly on efficiency, that Hydrogen fuel cell vehicles are the long term future. "The efficiency of a hydrogen ICE is circa 25% and that of a HFCV is 60%; this is three times better than today's petrol fueled engines (18-20% for a petrol ICE)." [1] While currently price is one of the main inhibitors to fuel cells, as more and more are produced, the costs will begin to go down. From 2002-2012, fuel cells overall price was reduced from $275/kW to $47/kW. Also, emissions wise, there is nothing that can compete with a fuel cell since the only emission is water.
As governments continue to fund and back projects to further develop hydrogen infrastructure and storage, society will see the world, slowly, change from a petrol based society to a hydrogen based world. As more hydrogen refilling stations are installed and a better, more efficient method of storage is developed, hydrogen will slowly take over petroleum's throne.
However, It is obvious, based mainly on efficiency, that Hydrogen fuel cell vehicles are the long term future. "The efficiency of a hydrogen ICE is circa 25% and that of a HFCV is 60%; this is three times better than today's petrol fueled engines (18-20% for a petrol ICE)." [1] While currently price is one of the main inhibitors to fuel cells, as more and more are produced, the costs will begin to go down. From 2002-2012, fuel cells overall price was reduced from $275/kW to $47/kW. Also, emissions wise, there is nothing that can compete with a fuel cell since the only emission is water.
As governments continue to fund and back projects to further develop hydrogen infrastructure and storage, society will see the world, slowly, change from a petrol based society to a hydrogen based world. As more hydrogen refilling stations are installed and a better, more efficient method of storage is developed, hydrogen will slowly take over petroleum's throne.
Article Sources
[1] Fuel-Cell (Hydrogen) electric hybrid vehicles By B.G. Pollet & I. Staffel, 2014
[2] Towards Sustainable Road Transport by Ronald M. Dell, Patrick T. Moseley, David A. J. Rand, 2014[3] http://www.rita.dot.gov/sites/default/files/publications/challenges_of_building/html/table_02_04.html
Other Sources
[1] Fuel-Cell (Hydrogen) electric hybrid vehicles By B.G. Pollet & I. Staffel, 2014
[2] Towards Sustainable Road Transport by Ronald M. Dell, Patrick T. Moseley, David A. J. Rand, 2014[3] http://www.rita.dot.gov/sites/default/files/publications/challenges_of_building/html/table_02_04.html
Other Sources
- https://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/compressed_hydrogen2011_7_brunner.pdf
- An overview of fuel cell technology: Fundamentals and Applications, by Sharah and Orhan, 2014
- Hydrogen fueled internal combustion engines by Verhelst & Wallner, 2009
- Recent progress in the use of hydrogen as a fuel for internal combustion engines By Verhelst, S., 2013
- http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/fct_h2_storage.pdf