Hydrail is the generic term denoting all forms of rail vehicles, large or small, which use on-board hydrogen as a source of energy to power the traction motors, or the auxiliaries, or both. Hydrail vehicles convert the chemical energy of hydrogen to mechanical energy either by burning hydrogen like in a hydrogen internal combustion engine vehicle, or by reacting hydrogen with oxygen in a fuel cell to run electric motors. Widespread use of hydrogen for fueling rail transportation is a key element of the proposed hydrogen economy. The term is now used extensively by research scholars and technicians around the world. However, no hydrail rail systems are currently in public use.
Hydrail vehicles are usually hybrid vehicles and also have renewable energy storage solutions like batteries or super capacitors, for regenerative braking, which improves efficiency and lowers the amount of hydrogen storage required. Potential hydrail applications include all types of rail transport, like commuter rail; passenger rail; freight rail; light rail; rail rapid transit; mine railways; industrial railway systems; trams; and special rail rides at parks and museums.
International Hydrail Conference
Each year Appalachian State University and others organize an International Hydrail Conference, bringing together the scientists working on the technology around the world in order to expedite deployment of the technology for environmental, climate and energy security reasons. In 2010, the Sixth International Hydrail Conference was hosted in Istanbul, Turkey, by the United Nations Industrial Development Organization and the Turkish State Railways. Previous International Hydrail Conferences have been held in Herning, Denmark; Valencia, Spain; Charlotte, North Carolina; and Salisbury, North Carolina. Presenters at these conferences have included national and state/provincial agencies from the USA, Canada, Denmark, Italy, Japan, Korea, Russia, Turkey, the United Kingdom, the European Union and the United Nations (UNIDO-ICHET). At this writing, the 2011 Hydrail Conference is scheduled to be convened in Seoul, South Korea, hosted by the Korean Railway Research Institute. The United States Environmental Protection Agency has co-sponsored all three of the International Hydrail Conferences held in the USA.
The term hydrail was coined on April 17, 2004 in the International Journal of Hydrogen Energy as a search engine target word to enable scholars and technicians around the world working in the hydrogen rail area to more easily publish and locate all work done in the discipline.
A hydrolley is a streetcar or tram (trolley) using hydrail technology. The term (for hydrogen trolley) was coined at the Fourth International Hydrail Conference, Valencia, Spain, in 2008, as a research-simplifying search engine target word. Onboard hydrogen-derived power eliminates the need for trolley arms and overhead track electrification, reducing construction cost, visual pollution and maintenance expense. The term 'hydrolley' is preferred to 'hydrail light rail' or other combinations because of their connotation of external electrification.
History, projects and prototypes
- In 2002 the first 3.6 tonne, 17 kW, hydrogen-powered mining locomotive was demonstrated in Val-d'Or, Quebec.
- In April 2006 came the world's first hydrail railcar, which was developed by East Japan Railway Company 
- In October 2006, the Railway Technical Research Institute in Japan conducted tests on a fuel cell hydrail vehicle by Nuvera Fuel Cells.
- In April 2007, The mini-hydrail from the Taiwan National Science and Technology Museum and Taiwan Fuel Cell Partnership combination made its first educational ride.
- In 2007, The Railway Technical Research Institute in Japan built two 62 ton passenger cars, each with a 450 kW PEM fuel cell and a 150 kW battery.
- In 2008, the East Japan Railway Company in Japan tested its experimental "NE Train" hybrid train fitted with two 65 kW PEM fuel cells and 19 kWh lithium ion batteries for a short period in the Nagano area.
- In 2009, BNSF unveiled the first hydrail locomotive, powered by hydrogen fuel cells.
- In 2010, a 357-kilometre (222 mi) high-speed hydrail line was proposed in Indonesia. The rail link, now under feasibility study, would connect several cities in Java with a hydrogen-powered maglev system.
- The Hydrogen Train Project in Denmark is attempting to build Europe's first hydrogen powered train using hydrogen in an internal combustion engine.
- Graham-Rowe, D. (2008). "Do the locomotion". Nature 454 (7208): 1036. doi:10.1038/4541036a. PMID 18756218.
- Minkel, J. R. (2006). "A Smashing Bad Time for the United States". IEEE Spectrum 43: 12. doi:10.1109/MSPEC.2006.1665046.
- Jones, W. D. (2009). "Fuel cells could power a streetcar revival". IEEE Spectrum 46: 15. doi:10.1109/MSPEC.2009.5210050.
- Jones, W. D. (2006). "Hydrogen on Track". IEEE Spectrum 43: 10. doi:10.1109/MSPEC.2006.1665045.
- Delucchi, M. A.; Jacobson, M. Z. (2010). "Providing all global energy with wind, water, and solar power, Part II: Reliability, system and transmission costs, and policies". Energy Policy 39 (3): 1170–1190. doi:10.1016/j.enpol.2010.11.045.
- Marin, G. D.; Naterer, G. F.; Gabriel, K. (2010). "Rail transportation by hydrogen vs. Electrification – Case study for Ontario, Canada, II: Energy supply and distribution". International Journal of Hydrogen Energy 35: 6097. doi:10.1016/j.ijhydene.2010.03.095.
- Miller, A.I. (Atomic Energy of Canada Limited, Chalk River Laboratories), "Hydrail: an Adaptable, Low-Cost Alternative to Electrification", Hydrogen and Fuel Cells 2007, Paper 4.205.4, April 29-May 2, 2007, Vancouver, Canada
- Stan Thompson and Jim Bowman (2004) "The Mooresville Hydrail Initiative", International Journal of Hydrogen Energy 29(4): 438, in "News and Views" (a non-peer-reviewed section)
- Sandia Corporation (2004). Fuel-Cell-Powered Mine Locomotive. Sandia National Laboratories. Accessed 6 Feb 2011.
- Development of the World's First Fuel Cell Hybrid Railcar. (11 April 2006) East japan Railway Company. Accessed 6 Feb 2011.
- Nuvera Fuel cells (18 Oct. 2006). Successful Test Run of a Fuel Cell Railway Vehicle. Accessed 6 Feb 2011.
- World's first hydrogen fuel train tested in Taiwan. People's Daily (13 April 2007).
- Adamson, Dr. Kerry-Ann (July 2007). 2007-Niche transport survey (PDF). Fuel Cell Today.
- BNSF Railway and Vehicle Projects Demonstrate Experimental Hydrogen-Fuel-Cell Switch Locomotive. BNSF Railway (29 June 2009)
- "Indonesia high speed hydrogen train feasibility study". The Hydrogen Journal. 13 Jan 2010. Retrieved 25 March 2011.
- Adamrah, Mustaqim (8 Jan 2010). "RI could have a super high speed train as early as 2012". Jakarta Post. Retrieved 26 March 2011.
- China introduces first light-rail train with new-energy fuel cells. People's Daily (29 Nov. 2010)
- Europe's first hydrogen powered train. The Hydrogen Train Project.
- EU FP 6 HyRail Project
- Hydrail.org Appalachian State University
- Gaia Railways Hydrogen Train & Trolley Manufacturer