Energy resources hydrogen

In contrast to fossil energy resources such as oil, natural gas, and coal, which are unevenly distributed geographically, primary sources for hydrogen production are available virtually eveiywhere in the world. The choice of a primary source for hydrogen production can be made based on the best local resource. 

The fact that solar energy is an intermittent energy resource means that energy storage systems (e.g., batteries, ultracapacitors, flywheels, and even hydrogen) will be required if solar energy is to be utilized widely. In addition, a variety of toxic chemicals are used in the manufacture of PV cells however, studies of the risks associated with their manufacture and disposal indicate little threat to surroundings and the environment. 

Gas hydrates are non-stoichiometric crystals formed by the enclosure of molecules like methane, carbon dioxide and hydrogen sulfide inside cages formed by hydrogen-bonded water molecules. There are more than 100 compounds (guests) that can combine with water (host) and form hydrates. Formation of gas hydrates is a problem in oil and gas operations because it causes plugging of the pipelines and other facilities. On the other hand natural methane hydrate exists in vast quantities in the earth s crust and is regarded as a future energy resource. 

For each ton of hydrogen produced from hydrocarbons, approximately 2.5 t of carbon is vented to the atmosphere [44-47], However, for each ton of hydrogen produced from current coal technology, approximately 5 t of carbon is emitted to the atmosphere. Principally, C02 capture and sequestration is a precondition for use of these fossil fuels. However, the sequestration necessity varies, because the relative atomic hydrogen-to-carbon ratios are 1 2 4 for coal oil natural gas. There are two basic approaches to C02 sequestration either at the point of emission (in situ capture) or from the air (direct capture). In either case, C02 must be disposed off safely and permanently. With the capture and sequestration of C02, hydrogen is one path for coal, oil, and natural gas to remain viable energy resources [46]. Carbon sequestration technologies are discussed in detail in Chapter 17. 

Mohitpour, M., Pierce, C., and Hooper, R. The design and engineering of cross-country hydrogen pipelins. ASME Journal of Energy Resources Technology, 110,203-207,1988. 

Dillon, A.C., B.P. Nelson, Y. Zhao, Y.-H. Kim, C.E. Tracy, S.B. Zhang, Importance of turning to renewable energy resources with hydrogen as a promising candidate and on-board storage a critical barrier. Mater. Res. Soc. Symp. Proc. 895,115-122, 2006. 

Energy resource availability for hydrogen production between now and 2050. 

Hydrogen is of interest as a means to deliver gaseous fuel from non-fossil primary energy resources such as nuclear reactors, or high temperature solar collectors. It is believed that hydrogen may phase into the energy market at such a time when fossil-based fuels either become too expensive or environmentally unsatisfactory. Hydrogen and biomass are the only two potentially visible options at the present time for the gas industry if that does take place. 

These systems offer the opportunity to produce hydrogen from renewable resources in the mid-term (five to ten years). Using agricultural residues and wastes, or biomass specifically grown for energy uses, hydrogen can be produced using a variety of processes. 

Kotay, S.M., Das, D. 2008. Biohydrogen as a renewable energy resource prospects and potentials. Int J Hydrogen Energy 33 258-263. 

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