Supply options

Electrical resistance boilers use banks of fixed, immersion-type, resistance heating elements (typically sheathed in seamless copper, Incoloy 800, or 316SS) to provide an energy source that is contained within a carbon-steel pressure vessel. The vessel is provided with a sight glass and all normal boiler controls, valves, and regulators necessary for automatic operation. The vessel is generally well insulated and housed within an enameled metal cabinet. Various electrical supply options are available. 

Up to 20 classes are provided by the SETUP program so that various types of specimen can be processed in the same run. The program-supplied options are read from a text file on the disk and hence are easily changed. The operator may type in the name of any class not provided as a choice by SETUP. 

Figure 7.1. Alternative fuel supply options (Kruger, 2002, amended).

Country-specific features, such as different fuel supply options, expansion potentials for regenerative energy sources or political frame conditions have to be considered to cater sufficiently for their influence on the real decision options. 

If renewable targets are set, biomass gasification is the cheapest renewable hydrogen supply option however biomass has restricted potential and competition of end-use, for instance, with other biofuels or stationary heat and power generation. Biomass gasification is applied in small decentral plants during the early phase of an infrastructure roll-out and in central plants in later periods. 

The SSCHISM infrastructure model calculates the cost of the potential hydrogen pathway-supply options shown in Table 15.3 for 73 of the largest US urbanised areas and selects the cheapest supply pathway in each city at a specified market penetration. The cheapest pathway choice for any given city depends on the size of the city, level of demand, demand density, and local energy and feedstock prices. 

Since the proved reserves of conventional natural gas have declined in recent years, the need for new supply options was of primary importance in the 1979 research program. Forty-four projects are being undertaken this year to further the development of four new sources of gas supply. They are o Unconventional Natural Gas... 

The proven reserves of so called "conventional" natural gas have declined in recent years and the need for additional supplies and new supply options have been identified as a high priority requirement to benefit the gas consumers. Therefore, the GRI Gas Supply Program has been established to identify, evaluate, and develop new gas supplies that will guarantee abundant quantities of gaseous fuels for gas consumers in the future. To fulfill this objective the GRI Gas Supply Program has been divided into the following subprograms o Unconventional Natural Gas o SNG from Coal... 

Land-based biomass has a potential of providing from 7 to 1-1 quads/year of SNG if all available marginal land suitable for the growing of crops could be utilized. However, the doubtful availability of land and water for growing land-based biomass specifically for SNG production gives this supply option a lower priority than water-based biomass. The initial stage of the project concentrates on identifying natural species that will produce a maximum quantity of gas. 

The Department of Energy, I m afraid, has got to take some of the blame for the mixed-up signals that are being sent out to people, particularly people in industry who are buying natural gas and trying to understand what their supply options are going to be and whether they are going to be able to have it. 

Figure 1.1. Nitrogen supply options based on flowrate and nitrogen purity. (Copyright 2002 Air Products and Chemicals, Inc.)...

At very large scale, around a gigawatt and above, the principal supply options include carbonaceous fuels and nuclear energy. About 100 such plants would be able to supply the current world demand for hydrogen, about 42 million tons per year (ORNL, 2003), and about 20 such plants would be able to supply the current U.S. demand for hydrogen of about 9 million tons per year. 

H. S. Ong, Challenges ahead for Singapore s water supply. Seminar on Ensuring Singapore s Water Supply Options and Issues, Shangri-la Hotel, 10-11 Nov. (1997). 

Because hydrogen can be produced from a variety of feedstocks, at a wide range of sizes from city scale to household level, and delivered in various ways ranging from truck delivery of cryogenic liquid to gas pipeline delivery of compressed gas, there are many possible supply options. (To simplify the analysis, all supply options in this chapter assume delivery to motor vehicles of hydrogen as a compressed gas.) Near term supply options include ... 

Near term gaseous H2 supply options centralized reforming... 

FIGURE 5-1. Near term gaseous hydrogen supply options. 

Long term hydrogen supply options include ... 

Challenges Facing Long Term Supply Options... 

Each of these near-zero emission, long term hydrogen supply options faces significant challenges before it could be implemented on a global scale. 

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