A mathematical model was developed for estimating the energy-saving potential of household refrigerators in Japan. In the model, refrigerators were categorized into 44 classes by power consumption and volume. Number distribution of the refrigerators in each class used in a given year was estimated by the number balance of refrigerators disposed and produced in the year. The total power consumption was calculated from the distribution. The model well described the past trend of statistical data on the power consumption. Based on the model, the energy-saving potential in the future (up to 2010) was simulated by assuming several types of number distribution of the refrigerators shipped in the future, and the average period of use before disposal. It was found that the power consumption in 2010 could be as small as 73.7% of that in 1997 when the power-consumption efficiency of all the refrigerators produced after 2004 equals to that of the highest model produced in 1999. This assumption corresponds to a situation satisfying the New Energy-Saving Law of Japan (1999). The smaller volume and the shorter period of use before disposal also decreased the total power consumption, but those effects were not so large.
The auther had presented the prospecting procedure of long rangeover 100 years-world energy demand derived from population in 1994. This report is on the revising results of such prospecting procedure. This procedure depends on the prospect of world population, and world population has been prospected till 2150 by World Bank. So this procedure can be used to prospect the energy demand till 2150 theoretically. It has been found that the relation between rate of population growth and personal energy consumption of that year is represented by the quadratic equation. Also it is found that this relation has been kept about 20 years. Therefore certain personal energy consumption is calculated from the rate of population growth of the same year. In this report it is shown that the curve of quadratic relation is represented by the part of the ellipse, and developing path from underdevelping area to advanced area goes along such elliptical orbit. Energy demand of world and 6 continents from 1995 to 2100 is calculated. World energy demand in 2100 will be between 440×108 and 550×108 TCE. To simulate the developing path from underdeveloping area to advaned area, a part of ellipse is used. Such elliptical curve will be powerfull tool not only for prospecting energy demand but considering the release of CO2 which is thought one of materials having large effect on environment.
The fundamental heat balance was evaluated by numerical simulation for a long-term latent heat thermal energy storage system using supercooled phenomena. The supercooled thermal energy storage (Super-TES) stores thermal energy at temperatures lower than the melting point of the phase-change material, which reduces heat loss from the storage system. The thermophysical properties of disodium hydrogenphosphate dodecahydrate were used for the calculation. From the results of the calculation, we found that Super-TES contributes for saving available energy (exergy) more than for saving energy. Although the exergy efficiency is generally lower than the energy efficiency, the relation reverses when the storage material is kept in the supercooled condition. Super-TES exceeds conventional latent heat thermal energy storage (LHTES) in both energy and exergy efficiencies. The difference in efficiency between Super-TES and LHTES increases with increasing period of the storage in the supercooled condition.
In order to reduce emission of dioxins from fluidized bed incinerators, porous alumina particles were used as bed material instead of conventional bed material (sand). Poly vinyl chloride pellets were burnt in a bench-scale fluidized bed combustor. The emission of dioxins was reduced by employing porous bed material instead of non-porous sand.