Load-leveling devices

Zinc—bromine storage batteries (qv) are under development as load-leveling devices in electric utilities (64). Photovoltaic batteries have been made of selenium or boron doped with bromine. Graphite fibers and certain polymers can be made electrically conductive by being doped with bromine. Bromine is used in quartz—haUde light bulbs. Bromine is used to etch aluminum, copper, and semi-conductors. Bromine and its salts are known to recover gold and other precious metals from their ores. Bromine can be used to desulfurize fine coal (see Coal conversion processes). Table 5 shows estimates of the primary uses of bromine. 

R. Yeo, Application of Perfluorosulfonated Polymer Membranes in Fuel Cells, Electrolysis, and Load Leveling Devices, in Perfluorinated Ionomer Membranes, A. Eisenberg and H.L. Yeager (eds), ACS Symposium Series Number 180, American Chemical Society, Washington, DC, pp. 453-473 (1982). 

Applications of Perfluorosulfonated Polymer Membranes in Fuel Cells, Electrolyzers, and Load Leveling Devices... 

Cell efficiency is very often related to the transport properties of the membrane. This is particularly true for those load-leveling devices in which the kinetics of the cell reactions are fast. The ohmic overvoltage and current efficiency are largely determined by the membrane conductivity and reactant permeation, respectively. 

Yeo R S 1982 Applications of perfluorosulfonated polymer membranes in fuel cells, electrolyzers, and load leveling devices Perfluorinated lonomer Membranes ed A Eisenberg and H L Yeager (Washington, DC American Chemical Society) pp 453-73... 

The principal battery which is under development with a beta-alumina electrolyte is the sodium/sulphur system which operates at 300-400 C and has liquid electrodes. This is described in my second lecture to the summer school. The interest in this battery stems from its projected application as a traction battery for vehicles and as a load levelling device for power stations. For such applications the energy and power requirements are many orders of magnitude larger than for the solid state batteries described above and current densities of 200 mA/cm are commonplace. Liquid electrodes are therefore necessary to avoid electrode polarisation effects. The practical problems of developing these high temperature, high power level batteries are formidable and a substantial world-wide effort is involved. 

As noted from general experience, except for specific large inductive loads such as of furnace or rectifiers, the fundamental content of the load current is high compared to the individual harmonic contents. In all such cases, it is not necessary to provide a filter-circuit for each harmonic unless the current is required to be as close to a sinusoidal waveform as possible, to cater to certain critical loads or instruments and devices or protective schemes operating in the system, where a small amount of harmonics may lead to malfunctioning of such loads and devices. Otherwise only the p.f. needs be improved to the desired level. Also to eliminate a parallel resonance with the... 

The second alternative is an electronic load. This device is a circuit that has a controllable switch (typically a Darlington configured pair of bipolar transistors or a MOSFET) that can be modulated to conduct any level of current the user desires. An example of an electronic load circuit is presented in this chapter. The electronic load will be constructed piece by piece and tested separately. When all the pieces are constructed and simulated, the whole sum of the electronic load can be assembled and tested as a unit. 

The shedding list includes all electrical devices in the plant that can be turned off for some limited time period. At the top of the list are the low-priority users (sump pumps, HVAC equipment, etc.), whereas higher up on the list, there can be secondary users (pumps and other equipment that can be operated at partial load levels or cycled on and off). 

Inherently, hydrogen pipelines are wonderful energy storage devices. Therefore, they can both store the product of sources when the demand falls below supply and give up energy when demand rises above supply. Thus, they inherently load-level for constant output sources and can always absorb energy from intermittent and unpredictable sources. 

A variety of well-established macroscale SPE methods for nucleic acid extraction have been successfully transferred to microscale devices [10, 31-57]. Although the physical principles of these methods may be different (e.g., chaotropic interactions, electrostatic interactions, affinity interactions, etc.), micro-SPE protocols typically consist of three steps (1) selective adsorption of nucleic acids onto a solid phase (2) removal of contaminants by a washing step and (3) elution of the preconcentrated nucleic acids from the solid support using water or a low salt buffer [31]. Like their macroscale counterparts, micro-SPE devices possess a loading level of target material that is dependent upon the available surface area within the extraction bed and, thus, are manufactured either by packing the solid phase... 

MAJOR APPLICATIONS Power cable sheathing, prime conductor, energy load leveling systems, batteries, and signal processing devices. 

---