Sản Xuất Hydro Bền Vững
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#hydro #bền vững #năng lượng #phát thải môi trường #an ninh năng lượng #sản xuất hydro #hệ thống năng lượngTài liệu tham khảo
For the purpose of this discussion I use the following definition of the hydrogen economy: the production storage distribution and use of hydrogen as an energy carrier.
Jules Verne The Mysterious Island (available at http://www.literature-web.net/verne/mysteriousisland 1874).
P. Hoffmann The Forever Fuel: The Story of Hydrogen (Westview Press Boulder CO 1981).
D. Gregory, Sci. Am.228, (no. 1), 13 (January 1973).
Basic Research Needs for the Hydrogen Economy available at http://www.sc.doe.gov/bes/reports/files/NHE_rpt.pdf (current U.S. production is about 9 million tons of hydrogen per year).
G. Richard ILEA Leaf Winter 2002 (available at www.ilea.org/leaf/richard2002.html).
Energy Information Administration unpublished file data of the Coal Reserves Data Base (February 2004) available at http://www.eia.doe.gov/pub/international/iea2002/table82.xls.
A. Steinfeld Solar Energy in press (available online 3 February 2004).
Nuclear Production of Hydrogen Second Information Exchange Meeting–Argonne Illinois USA 2-3 October 2003 (Organisation for Economic Cooperation and Development Paris) (available at http://oecdpublications.gfi-nb.com/cgi-bin/OECDBookShop.storefront/EN/product/662004021P1).
J. A. Turner, Science285, 5428 (1999).
J. Ivy Summary of Electrolytic Hydrogen Production: Milestone Completion Report available at www.osti.gov/servlets/purl/15007167-aF4rPu/native/.
In any discussion concerning the efficiency of electrolyzers it is appropriate to use the higher heating value to calculate the efficiency. This corresponds to the isothermal potential (1.47 V = 39 kWh/kg) and represents the assumption that all the energy needed to split water comes from the electricity.
These figures are from the Energy Information Administration available at www.eia.doe.gov/cneaf/electricity/epm/tablees1a.html.
For an estimate of the amount of water needed for hydrogen-powered fuel cell vehicles we will assume a vehicle fuel economy of 60 miles per kg of H 2 that vehicle miles traveled = 2.6 × 10 12 miles/year (found at www.bts.gov/publications/national_transportation_statistics/2002/html/table_automobile_profile.html) and that 1 gallon of water contains 0.42 kg of H 2 . Total water required for the U.S. fleet = (2.6 × 10 12 miles/year)(1 kg of H 2 /60 miles)(1 gal H 2 O/0.42 kg of H 2 ) = 1.0 × 10 11 gallons of H 2 O/year. This represents the water used directly for fuel. If one considers all water uses along the chain; for example from construction of wind farms to the electrolysis systems (life cycle assessment) then the total water use would be in the range of 3.3 × 10 11 gallons H 2 O/year.
This is a life cycle analysis (M. Mann and M. Whitaker unpublished data). The United States used about 126 billion gallons of gasoline in 2001 [see link in ( 17 )].
See http://water.usgs.gov/pubs/circ/2004/circ1268/.
Contributions by D. Sandor for careful manuscript edits and by J. Ivy for Fig. 1 are gratefully acknowledged.