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This paper presents the effect of implementing interruptible loads (ILs) from the demand side for reserve allocation in an electricity supply system. A unit commitment (UC) objective function is used to incorporate the energy/reserve providers and to schedule energy and reserves simultaneously. An innate IL reliability modelling methodology is explicitly presented. A thermal unit system with demand-side participation is traversed by varying the size of the ILs, the reserve offer prices, and the value of lost load (VOLL). A penalty cost is imposed on IL service providers whose loads are supposed to be interrupted when initiated but fail to respond and grid service providers who are responsible for the maintenance of under-frequency relays (UFRs) and circuit-breakers (CBs) connected to ILs. The objective of this penalty cost proposal is to achieve a better and healthier energy supply system. The results in this paper provide useful insight into how the Demand Side Management and penalty scheme is capable of maintaining and/or improving the operation of the electricity supply system.

This article develops a general thermodynamic framework for the modeling of an irreversible absorption chiller at the design point, with application to a single-stage ammonia–water absorption chiller. Component models of the chiller have been assembled so as to quantify the internal entropy production and thermal conductance (UA) in a thermodynamically rigorous formalism, which is in agreement with the simultaneous heat-and-mass transfer processes occurring within the exchangers. Local thermodynamic balance (viz. energy, entropy, and mass balance) and consistency within the components is respected, in addition to the overall thermodynamic balance as determined by the inlet and outlet states of the components. For the absorbers, Colburn-and-Drew mass transfer equations are incorporated to describe the absorption process. Furthermore, the impact of various irreversibilities on the performance of chiller is also evaluated through the use of a general macroscopic equation.

We have developed a two-dimensional neutron imaging method using rectangular scintillators with wavelength shifting (WLS) fibers for neutron scattering experiments using a next-generation high-intense pulsed-neutron source. In the method, rectangular scintillators are arranged at longitudinal direction and transverse direction and WLS fibers are arranged on the four sides of these scintillators. Luminescences generated in the scintillator are absorbed by the four fibers and wavelength-shifted luminescences are detected by multi-anode photomultipliers. The position of incident neutron is decided by coincidence of the four signals. By preliminary experiments using 5 mm×5 mm×2 mm t 6 Li glass scintillators and 0.5 mm∅ WLS fibers, it was concluded that detection efficiency for thermal neutron was 13%. By scanning experiment using a 4×4 6 Li glass scintillator array neutron detection system, we obtained the clear spot of incident neutron beam that the cross talk was

In this article, a general definition of the process average temperature has been developed, and the impact of the various dissipative mechanisms on 1/COP of the chiller evaluated. The present component-by-component black box analysis removes the assumptions regarding the generator outlet temperature(s) and the component effective thermal conductances. Mass transfer resistance is also incorporated into the absorber analysis to arrive at a more realistic upper limit to the cooling capacity. Finally, the theoretical foundation for the absorption chiller T-s diagram is derived. This diagrammatic approach only requires the inlet and outlet conditions of the chiller components and can be employed as a practical tool for system analysis and comparison. (C) 2000 Elsevier Science Ltd and IIR. All rights reserved.

This article presents a thermodynamically consistent set of specific enthalpy, entropy, and heat capacity fields for LiBr-$H_2O$ solution. The temperatures span from 0 to $190^oC$, while the concentrations span from 0 to 75 wt%. The work is based on the empirical inputs of Duhring's gradient and intercept, specific heat capacity data at a reference concentration of 50 wt% and density data. These properties have been evaluated using most of the experimental data available in the literature. The present approach circumvents the issue of negative dew point at low temperatures and high concentrations. The information provided in this article could be useful for designers of absorption chillers.

A novel high-speed readout method of an imaging plate using wavelength-shifting fibers and a streak camera was developed aiming at real-time imaging. Imaging plate is scanned by a line-shape laser to read out all the pixels in one axis of imaging plate at the same time. Released photostimulated luminescences are detected from backside of the plate by the fibers and the streak camera. With preliminary experiments, it is confirmed that a radiation image can be measured by this method.

Conclusion: In prospective triggered scanning, reducing the tube voltage (100 kV) resulted in approximately 50% reduction in radiation. The removal of padding saw a further 50% reduction, resulting in radiation just above 1mSv. doi:10.1016/j.hlc.2010.06.487