Dissertations / Theses on the topic 'Industrial refrigeration'

Nowadays, energy management has gained attention due to the constant increment of energy consumption in industry and the pollution problems that this fact supposes. On this subject, one of the main industrial sectors, the food and beverage, attributes a great percentage of its energy expenditure to the refrigeration systems. Such systems are highly affected by operation conditions and are commonly composed by different machines that are continually interacting. These particularities difficult the successful application of efficient energy management methodologies requiring further research efforts in order to improve the current approaches. In this regard, with the current framework of the Industry 4.0, the manufacturing industry is moving towards a complete digitalization of its process information. Is in this context, where the promising capabilities of the data-driven techniques can be applied to energy management. Such technology can push forward the energy management to new horizons, since these techniques take advantage of the common data acquired in the refrigeration systems for its inner operation to develop new methodologies able to reach higher efficiencies. Accordingly, this thesis focuses its attention on the research of novel energy management methodologies applied to refrigeration systems by means of data-driven strategies. To address this broad topic and with the aim to improve the efficiency of the industrial refrigeration systems, the current thesis considers three main aspects of any energy management methodology: the system performance assessment, the machinery operation improvement and the load management. Therefore, this thesis presents a novel methodology for each one of the three main aspects considered. The proposed methodologies should contemplate the necessary robustness and reliability to be applicable in real refrigeration systems. The experimental results obtained from the validation tests in the industrial refrigeration system, show the significant improvement capabilities in regard with the energy efficiency. Each one of the proposed methodologies present a promising result and can be employed individually or as a whole, composing a great basis for a data-driven based energy management framework.
Avui en dia la gestió energètica ha guanyat interès degut a l'increment constant de consum per part de la indústria i els problemes de contaminació que això suposa. En aquest tema, un dels principals sectors industrials, el d'alimentació i begudes, atribueix bona part de percentatge del seu consum als sistemes de refrigeració. Aquests sistemes es veuen altament afectats per les condicions d'operació i habitualment estan formats per diverses màquines que estan continuament interactuant. Aquestes particularitats dificulten l'aplicació exitosa de metodologies d'eficiència energètica, requerint més esforços en recerca per millorar els enfocs actuals. En aquest tema, amb l'actual marc de la Indústria 4.0, la indústria està avançant cap una digitalització total de la informació dels seus processos. És en aquest context, on les capacitats prometedores de les tècniques basades en dades poden ser aplicades per a la gestió energètica. Aquesta tecnologia pot impulsar la gestió energètica cap a nous horitzons, ja que aquestes tècniques aprofiten les dades adquirides usualment en els sistemes de refrigeració per el seu propi funcionament, per a desenvolupar noves metodologies capaces d'obtenir eficiències més elevades. En conseqüència, aquesta tesi centra la seva atenció en la recerca de noves metodologies per a la gestió energètica, aplicades als sistemes de refrigeració i mitjançant estratègies basades en dades. Per abordar aquest ampli tema i amb el propòsit de millorar l'eficiència dels sistemes de refrigeració industrial, la present tesi considera els tres aspectes principals de qualsevol metodologia de gestió energètica: l'avaluació del rendiment del sistema, la millora de l'operació de la maquinària i la gestió de les càrregues. Per tant, aquesta tesi presenta una metodologia nova per a cadascun dels tres aspectes considerats. Les metodologies proposades han de contemplar la robustesa i fiabilitat necessàries per a ser aplicades en un sistema de refrigeració real. Els resultats experimentals obtinguts dels tests de validació fets en un sistema de refrigeració industrial mostren unes capacitats de millora significatives referent a l'eficiència energètica. Cadascuna de les metodologies proposades presenta un resultat prometedor i pot ser aplicada independentment o juntament amb les altres, formant una bona base per un marc de gestió energètica basat en dades.

An oil separator is a key component in an industrial refrigeration system as it prevents the compressor discharge oil creating a liquid film on the internal walls of the heat exchangers which leads to a reduction in efficiency of the system and increased operating costs. The Henry Technologies helical oil separator operates in refrigeration systems globally yet there is currently no available data on the performance of the unit. In this investigation the performance of the helical separator has been captured for a range of operating conditions using a custom built test facility. An assessment has also been made to determine the ability of current state-of-the-art computational models to predict the performance of the separator. The computational modelling approach used in this study was the Euler-Lagrange, which requires the solution of the continuous gas phase prior to the injection of the dispersed liquid phase. A Perspex replica of the helical separator being investigated was used to carry out LDA velocity component measurements and produce laser sheeting images which could be used to validate the single phase computational model. The unsteady nature of the swirling flow field in the separator, as a result of the PVC, required the implementation of the advanced LES turbulence model with high order discretization schemes. Separation efficiency and pressure drop measurements have also been obtained for various gas and liquid flow rates at 0 BarG and 3 BarG working pressures which clearly demonstrate that as the gas flowrate and operating pressure decreases the separation efficiency also decreases. The flow regime at the inlet to the separator consists of a heavily stratified liquid film with an annular dispersed droplet mist. Since the DPM model only models the trajectories of droplets; experimental data was obtained which characterised the performance of the separator subject to a droplet only mist with the liquid film being extracted and quantified just upstream of the inlet. The Malvern Spraytec laser diffraction apparatus was employed to determine the droplet size and distribution entering and leaving the separator allowing a grade-efficiency curve to be produced for the unit. Using the size, distribution, liquid flowrate and separation efficiency of the separator for the droplet mist only condition the DPM model was used to simulate the droplet trajectories with the validated single phase gas flow model. The droplet breakup and liquid film models were explored to determine the optimum modelling criteria which could predict the droplet separation efficiency obtained through the experimental testing. Using the information obtained through the experimental testing, computational simulations and the theory presented within the literature for droplet separation, design improvements have been suggested for the Henry Technologies separator. These include increasing the discharge flowrate through the no mesh separator, assessing a unit with a tangential inlet and compressed helix, designing a wire mesh attachment for the separator inlet and a swirl generator to be located in the centre tube. All design improvements resulted in increased separation efficiency but were coupled with an increase in pressure drop.

The development of a Semi-Open Refrigeration Cycle had been shown to be of economic value to the process of crystallisation. The experimentation took the form of several bench scale experiments to develop the designs of the individual vessels that were to constitute the final pilot plant. In view of the safety hazards involved with a plant contacting Sulphuric Acid and Liquid Butane, a substantial Hazop and HAZAN study has been carried out. From this data the pilot plant was constructed, with all necessary safety features. Computer monitoring and partial computer control was installed. The pilot plant was operated as a closed loop for extended periods, to enable the production of both Iron (2) and Copper (2) Sulphates to be produced on a continuous basis. The results showed that the crystals produced are of a small size, indicative of the instantaneous chilling of the mother liquor and are not contaminated to a significant degree with the refrigerant. The thermal efficiency of the cycle was lower than expected at 80%, but improvements in insulation coupled with the redesign of the condenser, eliminating the necessity for a separator vessel, should increase this to the expected 90%.

Os sistemas térmicos operam na maior parte do tempo fora de suas condições nominais de projeto. Nos sistemas de refrigeração industrial, a operação com carga térmica parcial ocorre em função de diversos fatores e o consumo de energia apresenta grande variação em função do ciclo de operação. Neste trabalho é proposta a otimização energética dos sistemas frigoríficos por compressão a vapor através da operação com regime variável para o ciclo frigorífico, especificamente através da operação com set-point de temperatura de evaporação variável. Para tanto é desenvolvido um modelo matemático para simulação dinâmica de um sistema de refrigeração industrial por compressão a vapor com refrigerante amônia (R-717) para o congelamento de alimentos composto basicamente de túnel de congelamento por circulação forçada de ar, evaporador com recirculação de líquido, reservatório de líquido a baixa pressão, compressores parafuso e condensador evaporativo atmosférico. São analisados através de simulação dois métodos para a variação do setpoint de temperatura de evaporação: a máxima temperatura de evaporação admissível e a minimização da potência no compressor. Os dois métodos são comparados ao sistema de controle de capacidade atualmente utilizado em instalações industriais.
Thermal systems operate most of the time at off-design conditions. In industrial refrigeration systems, the operation in partial loads occurs for many different reasons and the power consumption is a function of the refrigeration cycle pressures. This work proposes an energetic optimization of the compression refrigeration systems by the operation with a variable refrigeration cycle, specifically, by the operation with a variable suction temperature set-point. For this purpose it is developed a mathematical model for dynamic simulation of a industrial refrigeration compression system for food freezing with ammonia refrigerant (R717) formed by an air blast belt freezer, liquid overfeed evaporators, low pressure receiver, screw compressors and evaporative condenser. Two procedures for the suction temperature set-point variation are analyzed by simulation: the maximum suction temperature permitted and the compressor power consumption minimization. Both methods are compared with the capacity control system used in present industrial facilities.

As one of the oldest French firms, the Saint-Gobain Group has been widely well known for glass manufacturing before it started its distribution and packaging activities. Among its four different sectors, the Innovative Materials division comprises the flat glass industry and hence, Saint-Gobain Glass, one of its companies specialized in the manufacture of glass products. The project presented in this document aims to describe my internship experience in Saint-Gobain Glass as well as the development of the mission I was assigned: To collect and update all the market data by geographic region concerning the commercial refrigeration and home appliances segments. This last one approaches particularly the domestic refrigerators and ovens. Therefore, this document first gives a general overview of the group and the company Saint-Gobain Glass. Then, it gives an introduction to the problem that arose in the company and the succeeding need of performing this study in order to understand better the environment conditions and acquire a larger market share in those segments together with a literature review that encompasses the activities developed: market research and the selection of foreign markets. Once these concepts have been defined, the planning of the assignment and the sources of information used will be detailed. Like this, the document arrives to the conclusion of the project and consequently, the completion of my internship in SGG. Based on the results shown and on my point of view several recommendations are given regarding some next marketing actions as well as a selection of countries that according to the findings described provide better opportunities for SGG´s success in the appliances segments.

Dissertação de Mestrado em Segurança Alimentar
RESUMO - Com o intuito de tornar possível o consumo de água de coco fora das regiões produtoras, torna-se fundamental a sua industrialização. O processamento térmico é usado como forma efetiva na conservação dos alimentos. Entretanto, em alguns casos o uso do calor pode afetar o produto final de forma negativa, levando a alterações sensoriais e físico químicas do produto. Alguns processos não térmicos vêm sendo aplicados para a conservação de alimentos sem causar os efeitos adversos do uso do calor. Um desses processos é o tratamento de alimentos com luz ultravioleta, que tem sido bastante estudada pela eficiência na inativação microbiológica em água, sucos e em superfícies de diversos materiais. Este trabalho tem por objetivo a avaliação microbiológica de amostras de água de coco processada industrialmente com aplicação de raios ultravioletas de forma experimental combinada com diferentes tratamentos térmicos, como congelação e refrigeração, visando a conservação e segurança do produto final para o consumidor. As análises realizadas consistiram na Pesquisa de Salmonella spp, (ISO 6887-5:2010) e Escherichia coli (ISO 4831:2012), quantificação de coliformes totais e termotolerantes (ISO 4831:2012), mesófilos totais (ISO 6611:2004) e bolores e leveduras (ISO 4833-1:2013). Verificou-se a diminuição da carga microbiológica das amostras tratadas com ultravioleta quando comparadas com amostras submetidas a outro tratamento térmico, resultados compatíveis com os obtidos em estudos semelhantes em sumos. Para validação dos protocolos é fundamental que este estudo seja desenvolvido com um número maior de amostras, diferentes lotes e pesquisa de outros grupos de microrganismos.
ABSTRACT - In order to make it possible to consume and commercialize coconut water in distant regions from the production sites, industrialization of coconut water production is needed. During the bottling procedure for coconut water, the fruit goes through an external cleaning before opening. Thermal processing is an effective way to preserve food. However, in some cases the use of heat can negatively affect the final product, leading to sensorial and physical-chemical changes. Some non-thermal processes have been studied and applied to preserve food without causing the adverse effects of using heat. One of these processes is the treatment of food with ultraviolet light, which has been studied extensively for its efficiency in microbiological inactivation of water, juices and on surfaces of different materials. This work aimed to perform a microbiological evaluation of industrially prepared coconut water samples with the application of ultraviolet light combined with different thermal treatments, such as freezing and refrigeration, aiming at the conservation and safety of the final product for the consumer. The analyzes performed consisted of the identification of Salmonella spp, (ISO 6887-5: 2010) and Escherichia coli (ISO 4831: 2012), quantification of total and thermotolerant coliforms (ISO 4831: 2012), mesophiles (ISO 6611: 2004) and molds and yeasts (ISO 4833-1: 2013).Results revealed a decrease in the microbiological load of samples treated with ultraviolet when compared to samples submitted exclusively to thermal treatment. In future studies, for protocol validation purposes it will be essential to include a higher number of samples, belonging to different batches and also to investigate other groups of microorganisms.
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I magazzini refrigerati per alimenti rappresentano una grande parte della domanda di energia nel settore della refrigerazione. Nel seguente studio sono state analizzate le influenze di diverse configurazioni e tecnologie nei sistemi di refrigerazione industriale. Dallo studio della letteratura emerge l’assenza di una chiara metodologia per valutare le prestazioni energetiche dei sistemi di refrigerazione industriali e una base di riferimento per quantificare l'effetto delle azioni per migliorare tali prestazioni. L’obiettivo di questo lavoro è quello di contribuire ad accrescere la consapevolezza del ruolo di alcune funzionalità di progettazione sul comportamento generale del sistema e di definire una metodologia per il miglioramento degli indici di prestazione energetica di aziende operanti nel settore della catena del freddo alimentare attraverso la modellazione e la simulazione degli impianti. Un sondaggio tra le aziende italiane in questo specifico settore insieme all'analisi di simulazione sono utilizzati per presentare lo stato dell'arte nei sistemi di refrigerazione industriale e per quantificare l'effetto di potenziali miglioramenti tecnologici. Lo studio, a partire dalle simulazioni effettuate attraverso i dati forniti dall’azienda, mira a stabilire una possibile correlazione tra gli indicatori di prestazione energetica e un numero limitato di parametri dei sistemi energetici, in termini di produzione, volumi e consumo di energia. La valutazione comparativa delle misure di risparmio energetico fornisce una metodologia per valutare l’effettivo risparmio energetico in funzione di un numero limitato di parametri.
Refrigerated food warehouses represent a large part of the energy demand in the refrigeration sector. In the following study, the influences of different configurations and technologies in industrial refrigeration systems were analyzed. The study of the literature shows the absence of a clear methodology for assessing the energy performance of industrial refrigeration systems and a reference base for quantifying the effect of actions to improve these performances. The aim of this work is to contribute to raising awareness of the role of some design functions on the general behavior of the system and to define a methodology for improving the energy performance indices of companies operating in the food cold chain sector through plant modeling and simulation. A survey of Italian companies in this specific sector together with simulation analysis are used to present the state of the art in industrial refrigeration systems and to quantify the effect of potential technological improvements. The study, starting from the simulations carried out through the data provided by the company, aims to establish a possible correlation between the energy performance indicators and a limited number of parameters of the energy systems, in terms of production, volumes and energy consumption. The comparative evaluation of energy saving measures provides a methodology for assessing the actual energy saving based on a limited number of parameters.

Dans les grands systèmes de réfrigération, l’utilisation de réfrigérants comme lubrifiants, à la place des huiles, simplifie la conception du système, l’allège et réduit son impact environnemental. La très faible viscosité du réfrigérant conduit à une épaisseur de film séparant les deux surfaces comparable à leur rugosité. Néanmoins, des travaux expérimentaux avec le réfrigérant R1233zd suggèrent que la lubrification est possible dans ces conditions grâce à la formation d’une couche adsorbée sur la surface d’oxyde de fer. Les analyses expérimentales in situ dans le contact sont très difficiles à cause des conditions de fort confinement et haute pression. C’est pourquoi une approche numérique multi-échelles est développée, afin d’étudier l’impact des réactions physico-chimiques à l’interface réfrigérant-surface sur les propriétés de lubrification. La théorie de la fonctionnelle de la densité est utilisée pour quantifier au niveau quantique, l’adsorption d’une molécule de réfrigérant sur une surface d’oxyde de fer. Des énergies de liaison allant de -0.92 eV à -0.22 eV sont observées et reliées à différents cas d’adsorption. Ces résultats sont exploités pour paramétrer un champ de forces interfacial, qui prédit des structures moléculaires à l’interface, différentes de celles obtenues avec des potentiels basés sur les règles de mélange classiques. Des simulations de dynamique moléculaire utilisant ce champ de forces paramétré confirment l’existence d’une couche fortement adsorbée de R1233zd sur une surface d’oxyde de fer. Avec des surfaces atomiques lisses et seulement 2 nm d’épaisseur de film de réfrigérant, les couches adsorbées résistent à des pressions allant jusqu’à 4 GPa et des vitesses de cisaillement atteignant 100 m/s. Une valeur minimale de 5 molécules de réfrigérant par nm² est nécessaire à la formation de deux couches adsorbées à 0.5 GPa. De plus, des simulations en cisaillement avec une surface rugueuse prédisent une rupture totale du film à environ 13 GPa
In large refrigeration systems, using the refrigerant as lubricant instead of oil can help to simplify the design, lighten the systems, and reduce their environmental impact. However, the very low viscosity of refrigerants leads to ultra-thin films separating the surfaces, with a thickness comparable to surface roughness. Nevertheless, experiments with the R1233zd refrigerant suggests that lubrication is still possible in that situation thanks to an adsorbed layer formed on iron oxide surfaces. Experimental in situ analysis area is very difficult because of high confinement and high pressure. That is why a multiscale numerical approach is developed here, to explore the impact of chemical reactions and physical processes at the refrigerant-surface interface on large-scale lubrication properties. Density functional theory is used to quantify the adsorption of a refrigerant molecule on an iron oxide surface at the quantum level. Binding energies ranging from -0.92 eV to -0.22 eV are measured and related to different adsorption cases. These results are then used to parametrize an interfacial force field, whose predictions of interfacial molecular structure differs from those obtained using potentials based on standard mixing rules. Large-scale molecular dynamics simulations involving this parametrized force field confirm the existence of a strongly adsorbed layer of R1233zd molecules on iron oxide surface. With atomically smooth surfaces, and a refrigerant film thickness as small as 2 nm, the adsorbed refrigerant layers resists pressures as high as 4 GPa and sliding velocities as high as 100 m/s. A minimum value of 5 refrigerant molecules per nm² is necessary to the formation of two adsorbed layers at 0.5 GPa. Moreover, sliding simulations with a rough surface reveal total film breakdown for ca. 13 GPa

Studien är utförd åt Freezing Food Småland Öland AB. Syftet med undersökningen var att ge förslag på åtgärder som minskar anläggningens energibehov samt att beräkna återbetalningstid för åtgärder. Genom användningen av simuleringsprogramvara tillsammans med data från praktiska mätningar så testades olika förändringar i anläggningen. Studien resulterade i förslag på en höjning av frysrumstemperaturen och temperaturen i LTB1. Dessa åtgärder höjer anläggningens köldfaktor och minskar energibehovet. Förslag för att få bukt på istillväxten är att isolera av komponenter så som rör och ventiler. Isolering ger en energibesparing och en minskad risk för korrosion. Genom belastningstester framkom det att kompressorerna arbetar ofördelaktigt så förslag på lämpliga driftområden togs fram för att öka verkningsgraden och minska underhållskostnaderna och energibehovet. Anläggningen visade sig vara väl dimensionerad mot transmissionsförluster men att golvvärmen står för en oproportionerligt stor del av förlusterna i förhållande till dess yta.
The study is conducted for Freezing Food Småland Öland AB. The purpose of the study was to propose measures to decrease the facility’s energy demand and to calculate the payback time for these suggestions. By means of using simulation software along with data from practical measurements different configurations in the facility were tested. The study resulted in suggestions consisting of an increase of the temperature in the freezing room and the temperature in LTB1.Those suggestions increases the facilities COP and decreases the energy consumption. Proposals to curb the ice growth are the insulation of components such as pipes and valves. Insulation results in a small decrease in energy demand but greatly increases the accessibility and also decreases the risk of corrosion. Through load tests conducted on the compressors it showed that the compressors were not driven in the optimal load range, suggestions were made for operation in a more favourable load range. Thus increasing the efficiency and cutting the maintenance costs. From the results it is shown that the facility is well built and dimensioned against thermal transmission. Though it turned out that the floor heating accounts for a disproportionate amount of the thermal transmission.

Vapour-compression refrigeration systems represent one of the most relevant fields in terms of energy consumption. Among the research works aimed at reducing their environmental impact, those related to control systems are appealing, since they usually involve lower costs than interventions at system level and directly affects the energy consumption. In this work, a library of models able to reproduce the dynamics of the main components of a vapour-compression refrigeration machine has been developed in Matlab/SIMULINK to supply the building blocks to investigate the effects of different control strategies on the energy performance and on the control quality of the system. To obtain models with low computational cost, the switched moving-boundary approach was adopted for the mathematical model of the heat exchangers. Firstly, the models were numerically verified, using the Matlab toolbox Thermosys as a benchmark. A good agreement between the predictions of the two models was highlighted in the simulation of an air-to-air refrigerating machine; moreover the in-house models showed a better repeatability in the prediction of important quantities like refrigerant superheating, subcooling and charge. The dynamic models were also experimentally validated, comparing their predictions with the experimental data acquired on a water-to-water refrigerating machine equipped with brazed-plate heat exchangers. Results showed a very good agreement between numerical and experimental data, also in terms of electric power absorption and COP, thus proving the model usefulness in transient energy analysis. The effects of the suction accumulator and liquid receiver on the dynamics of the machine were also investigated. A novel lumped-parameter model combining the dynamics of the condenser and of the receiver was developed, allowing the coexistence of a non-zero subcooling at the condenser outlet and a partial filling condition of the receiver. An improvement in the prediction of the refrigerant pressure and temperature at the compressor outlet was highlighted.

Para avanzar en el estudio de la concentración espacial de cultivos, se ha elegido el caso de la manzana, la pera y el melocotón en Lleida, desde 1962 a 2000. La evolución de ese fenómeno se ha estudiado mediante técnicas de equilibrio espacial y análisis shift share, encontrándose una pauta espacial de comportamiento distinta entre la manzana y la pera por una parte y el melocotón por otro.
En el caso de las técnicas shift share se ha modelado el efecto diferencial como el resultado de un juego de suma nula, y suponiendo que las transferencias de efectos son más probables hacia las regiones más cercanas, se ha avanzado una explicación de las transferencias de superficie que se produjeron entre 1962 y 2000.
La diferencia encontrada en el distinto comportamiento espacial de esos cultivos se ha atribuido a la susceptibilidad de cada cultivo para ser conservado frigoríficamente. Se ha desarrollado un modelo que relaciona los incrementos de la capacidad en la industria frigorífica y de la superficie.
In order to move forward in spatial crop concentration, we have chosen apple, pear and peach in Lleida, from 1962 to year 2000. We have supposed that agglomeration causes are similar in these crops, due to production technology and their surfaces. The believed crops' agglomeration in Lleida has been explained by an income classification. Evolution of this phenomenon has been studied by spatial equilibrium methods and shift-share analysis, and we have found that there exists a spatial behaviour guide which is different between apple and pear and peach on the other hand.
In shift-share analysis differential effect has been modelled as null sum game, and supposing that interchange of effects is more probable between near regions, we have advanced one explanation about surfaces trade off.
Crops have showed different spatial behaviours. These differences have been attributed to their aptitude for being preserved in cold-storage. A model has been developed in order to relate cold increases with surface increases in Lleida.

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In this work, the simulation and design of absorption refrigeration systems was performed, in order to evaluate its performance. Specific software capable to simulate and design such systems was elaborated, using structured programming language FORTRAN. This was a complete study of all components of the system and specifying their capacities. It has accomplished the project's absorber system, using the methodology of the project for Tinker heat exchangers. The absorber designed was a shell and tube heat exchanger, vertical, with flow of ammonia steam and of the water solution on the side of the shell and cooling water pipes. On verification of the proposal design, it was used the Wilke correlation, developed for settings in film condensation on vertical tubes. After developing of the program, they have been designed systems to attend certain specific conditions of heat load and temperature regime similar to real systems (small-sized refrigerator, air conditioning in a public environment and medium-sized industrial installation). Results from energy consumption were compared with similar systems by compression of steam. The program established with a good degree of correlation the energy demands of all systems tested, proving its reliability. The results showed that the refrigeration system for absorption has, in addition to good capacity for cooling, a low operational cost when compared to conventional systems by compression, for the studied cases.
Neste trabalho realizou-se a simulação e o projeto de sistemas de refrigeração por absorção, visando estudar-se sua eficiência. Criou-se um programa capaz de auxiliar no projeto e na simulação de sistemas desta natureza, utilizando programação estruturada em linguagem FORTRAN. Realizou-se um estudo completo de todos os componentes do sistema, especificando-se suas capacidades, e o projeto do absorvedor do sistema, utilizando a metodologia de projeto de Tinker para trocadores de calor. O absorvedor projetado foi um trocador de calor tipo casco e tubos, vertical, com fluxo do vapor de amônia e da solução aquosa no lado do casco e água de resfriamento nos tubos. Na verificação da geometria proposta, utilizou-se a correlação de Wilke, desenvolvida para configurações de condensação em película sobre tubos verticais. Após o desenvolvimento do programa, projetaram-se sistemas para atender algumas condições específicas de carga térmica e regime de temperaturas semelhantes a sistemas reais (refrigerador de pequeno porte, climatização de um ambiente público e câmara industrial de médio porte). Os resultados de consumo energético foram comparados com sistemas similares por compressão de vapor. O programa determinou com bom grau de correlação as demandas energéticas de todos os sistemas testados, comprovando a sua confiabilidade. Os resultados obtidos mostraram que o sistema de refrigeração por absorção possui, além de boa capacidade de refrigeração, um baixo custo operacional quando comparado aos sistemas por compressão convencionais, para os casos estudados.

Mestrado em Engenharia Mecânica
O presente documento descreve um trabalho feito em cooperação com a empresa Mercatus Portugal, Refrigeração e Estruturas Metálicas d'Alagoa, S.A. O objetivo do trabalho residiu na melhoria do desempenho energético de um equipamento previamente existente na empresa. Em primeiro lugar, caraterizou-se do produto comercializado atualmente. Com base nesta caraterização, foram propostas algumas alterações que visam a otimização energética do equipamento. As medidas propostas foram integradas num equipamento real e testadas laboratorialmente sob condições controladas. Para que se possa de nir o protótipo nal com as melhores caraterísticas, todas as alterações foram testadas nas mesmas condições. Foram testadas alterações a vários níveis, como a ventilação interna, grupo frigorí co e controlo. O protótipo nal consegue uma poupança energética de 23,76% relativamente ao produto inicial. Para o cliente nal, o investimento monetário que terá que ser feito relativamente ao produto inicial tem retorno em 3 anos e 10 meses.
This document describes work done in cooperation with the company Mercatus Portugal, Refrigeração e Estruturas Metálicas d'Alagoa, S.A, The objective lies in improving the energy performance of a previously existing equipment. Firstly the initial product was characterized. Then, a few changes have been proposed in order to improve the energy performance of this equipment. The proposed measures have been incorporated into a real equipment and tested on a laboratory under controlled environment. In order to set the nal prototype with the best features, all the changes were tested under the same conditions. Changes have been tested at di erent levels, such as internal ventilation, refrigeration unit and control system. The nal prototype achieves energy savings of 23,76 % when compared to the initial product. For the nal customer, the monetary investment compared to the original product will be recovered in 3 years and 10 months.

Terracotta vessels are about understanding how we can store food by using a new product solution and how we could use less energy and waste less food in doing so. This project is an attempt to minimise the energy usage in our homes but also to gain greater understanding about the food we choose to bring into our homes and what we can do to avoid throwing it away.

Thesis (M.S.)--University of Wisconsin--Madison, 2000.
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Dissertação de Mestrado em Energia para a Sustentabilidade apresentada à Faculdade de Ciências e Tecnologia
A eficiência energética tornou-se um dos assuntos/temas mais emblemáticos das políticas energética e ambiental da União Europeia, sendo o elemento-chave para se atingirem os objetivos do “Programa 20-20-20”, até 2020. A atividade relacionada com a aplicação da refrigeração para a transformação e conservação de alimentos corresponde a um sector industrial com elevada representatividade em termos de volume de negócios, seja em Portugal, na União Europeia ou mesmo a nível mundial. Neste contexto, as instalações e sistemas de refrigeração têm sido identificados como sendo as áreas com maior potencial para a implementação de medidas de eficiência energética e de poupança de energia.Para ultrapassar a falta de regulamentação aplicável à predominância das pequenas e médias empresas, têm sido implementados alguns programas de eficiência energética. No entanto, têm-se mostrado insuficientes na transferência dos resultados e recomendações à indústria agroalimentar. Neste sentido, é expectável que o uso de ferramentas de simulação energética aplicadas às instalações, sistemas de refrigeração e outros sistemas de energia, possa fornecer informações fidedignas e úteis para este setor industrial. A metodologia de simulação dinâmica requer uma validação apropriada, comparando os resultados com a desagregação de consumos e análise energética, obtidos a partir de auditorias energéticas detalhadas. Por outro lado, o modelo de simulação e, em particular, os modelos dos sistemas energéticos têm de ser parametrizados corretamente, de forma a obter uma convergência precisa para o consumo anual de energia. Contudo, a parametrização e caracterização técnica dos sistemas de refrigeração, bem como as técnicas de simplificação utilizadas em programas de simulação dinâmica, exigem um conhecimento aprofundado das soluções tecnológicas existentes no mercado, consolidado na fundamentação teórica dos ciclos termodinâmicos que dentro deles ocorrem.Desta forma, é apresentada uma revisão tecnológica, fundamentada na análise teórica do ciclo de compressão de vapor (entre outros, sumariamente analisados), juntamente com seus componentes e configurações mais comuns, tendo sempre em perspetiva a eficiência energética e as questões ambientais. É igualmente elaborada uma análise dos sistemas, configurações, tipos de equipamentos e fluidos refrigerantes mais utilizados a nível global, e em particular em Portugal, sendo esta última constituída de acordo com a informação de um projeto de investigação nacional sobre a utilização de energia e o consumo energético dos sistemas de refrigeração no sector agroindustrial.Finalmente, é apresentado um breve registo histórico da evolução dos programas de simulação energética, ferramentas essenciais na avaliação de medidas de eficiência energética, culminando com a análise da viabilidade técnica do software EnergyPlus, para modelação de sistemas de refrigeração industrial. Nesta perspetiva, identificam-se os procedimentos e caminhos a seguir em trabalhos futuros para a realização de exercícios detalhados de simulação energética de instalações industriais de refrigeração, que permitam evidenciar a sua mais-valia no estudo de medidas de eficiência energética.
Energy efficiency has become one of the most iconic issues/themes from the European Union’s energy and environmental policies, being the key element to reach the goals of the “20-20-20 Programme” by 2020. Regarding the turnover, the activity related to the use of refrigeration equipment for food processing and cold storage corresponds to a high representative industry sector, either in Portugal, in the European Union, or even worldwide. In this context, both facilities and refrigeration systems have been identified as being areas having the greatest potential for the implementation of energy-efficiency and energy-saving measures.Overcoming the lack of regulations applicable to the predominance of small and medium-sized enterprises, some energy-efficiency programmes have been implemented. However, they have proven to be insufficient on transferring results and recommendations to the agro-food industry. In this context, it is expected that the use of energy simulation tools applied to the refrigeration systems and facilities, and to other energy systems, would be able to provide reliable and useful information for this industrial sector. The dynamic simulation methodology demands an appropriate validation, comparing results with consumption breakdowns and energy analysis, obtained from detailed energy audits. On the other hand, the simulation model, and particularly the energy systems models must be correctly parameterized, in order to achieve an accurate convergence for the annual energy consumption. Nevertheless, the parameterization and technical characterization of the refrigeration systems, as well as simplification techniques commonly-used in dynamic simulation, require a thorough knowledge on the existing technological solutions, supported by theoretical fundamentals from the thermodynamic cycles taking place in it.Thus, a technological overview is presented, based on the theoretical analysis of the vapor compression cycle (among others, briefly analyzed), along with its components and most-common configurations, regarding always the energy efficiency and the environmental issues. An analysis of the most widely used systems, configurations, equipment types and refrigerants is also carried out at a global level, and then in Portugal, in particular, being the latter supported by the information from a national research project on the energy-use and energy consumption of the refrigeration systems in the agro-industry sector.Finally, a brief historical remark is presented aiming the evolution of the energy simulation programs, essential tools in the evaluation of energy-efficiency measures, culminating in the analysis of the technical feasibility on using the EnergyPlus software for modelling industrial refrigeration systems. Following this perspective, procedures and paths to be taken in future works, to perform detailed exercises on energy simulation of industrial refrigeration systems and facilities, are identified in order to demonstrate their added value for the study of energy-efficiency measures.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1998.
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Artificial ground freezing (AGF) is a process used to strengthen soil and rock by freezing trapped pore water. Freezing is accomplished by pumping calcium chloride brine, chilled to approximately – 30˚C in ammonia refrigeration plants, through heat exchangers drilled into the ground. A knowledge gap exists in the field of AGF regarding the relationship between the performance of the refrigeration plants and the ground heat removal process. The coupling of these two aspects of AGF requires knowledge of the plant’s refrigeration capacity as a function of many factors; the most important of which is the temperature of the brine returning from the freeze pipes. However, refrigeration plant manufacturers do not provide sufficient information about the plant’s performance as a function of brine temperature. Typically, AGF plants are only rated at one operating point due to the impracticality in experimentally rating such large plants and the lack of any standard test methods. Refrigeration system models available in the existing literature do not emulate the compressor control system responsible for preventing compressor overloading. Therefore, the goal of this research is to develop a model that can predict the performance of an AGF refrigeration plant over a range of operating points, using plant specifications that are readily available in the documentation provided by the manufacturer of the plant. To fill the knowledge gap, a thermodynamic model is developed of an existing 1500 TR AGF plant at Cameco’s Cigar Lake mine. The Cigar Lake plant uses flooded shell-and-tube evaporators, two-stage economized twin screw compressors, and air cooled condensers packaged into five refrigeration modules. Each component in the system, including the evaporator, compressor, and condenser, is modeled individually, and then the individual models are combined to calculate the overall system capacity. The model emulates the behavior of the compressor’s slide valves, which are used to limit the plant capacity, limit suction pressure, control intermediate pressure, and control the discharge pressures in the system. In addition, the model accounts for the effects of the oil injection into the screw compressors, which cools the compressors and seals the spaces between the lobes of the compressor rotors. The model is validated using operating data from the Cigar Lake plant, which was collected over a period of eight months by plant operators. After calibration, the modeled plant capacities and the temperature of the brine leaving the refrigeration plant are found to be in agreement with the measured capacities and brine temperatures. The overall plant capacity results match measured capacities within ±14%, and the predicted brine temperatures match the measured values leaving the plant within ±5%. The modeled capacities match the measured capacities within the uncertainty in the measured data. The simulation of the Cigar Lake plant demonstrates that the performance of the plant is highly dependent upon the temperature of the brine returning to the plant. For example, a ±10% change in brine temperature causes a 22% overall change in the capacity of the refrigeration plant. The simulation also demonstrates that, even with the plant’s air cooled condensers, changes in the ambient temperature have little effect on the performance of the plant with the existing equipment. Furthermore, the results show that the selected suction pressure of the second compression stage, or intermediate pressure, affects the performance of the refrigeration plant. These findings lead to important plant performance optimization opportunities. An optimization study using the model demonstrates that, by selecting a lower intermediate temperature than what the existing literature suggests, an improvement in overall refrigeration plant capacity of 3% can be achieved. Additional simulations identify the brine tank, which allows for different brine flow rates to exist on the field and plant side of the tank, as an inefficient component in the system. The brine tank not only cools the brine returning from the field before it is pumped to the refrigeration modules but it allows heat to be transferred between the warm and cold brine. By eliminating the tank, plumbing all of the refrigeration modules in parallel, and installing appropriately sized evaporators, the capacity of the refrigeration plant can be increased by 17%. Further capacity gains can be realized by upgrading the evaporators to increase their capacity.

Dissertação de mestrado em Engenharia Mecânica (Engenharia do Ambiente) apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
Nos edifícios industriais de refrigeração, a preocupação com a eficiência energética é cada vez mais importante, de modo a manter os seus produtos num nível adequado para chegar em qualidade ao consumidor. Uma construção apropriada pode ser crucial na condição final quer em termos energéticos, quer em termos económicos. A análise térmica é também importante para perceber a evolução da temperatura nos elementos construtivos e assim conhecer o estado físico da sua estrutura e as suas condições de armazenamento. Outros factores, como a localização do espaço, dimensões das câmaras de refrigeração, metodologia de trabalho, tipo de produto armazenados, são condicionantes decisivos na eficiência energética deste tipo de estrutura. Neste sentido, este estudo foca-se nas características da envolvente das câmaras de refrigeração, onde se estudaram as soluções construtivas, nomeadamente ao nível das pontes térmicas lineares e das infiltrações ou danificações correntes nos elementos de construção de um determinado edifício industrial de refrigeração. A temperatura interior de um espaço refrigerado terá sempre valores muito mais baixos de temperatura que o espaço exterior envolvente, assim, as cargas térmicas por condução nas fachadas do edifício de refrigeração e os ganhos de calor pelas envolventes são os principais pontos analisados. Estes parâmetros são factores importantes face aos consumos energéticos e custos de manutenção da indústria de refrigeração e para os analisar pormenorizadamente, foi usado, como ferramenta de cálculo dos coeficientes e resistências térmicas das envolventes, o programa THERM. Nesta dissertação é apresentado um caso de estudo de um edifício de conservação de peixe onde se pretendeu encontrar uma solução de poupança eficiente, aplicando alternativas de execução e de novos melhoramentos possíveis. Por fim, são apresentadas novas propostas de trabalhos futuros no âmbito da indústria de refrigeração.
In refrigeration buildings, the concern for energy efficiency is increasingly important to preserve their products to reach appropriate quality to the consumer. A suitable building can be crucial in the final condition in terms of energy and in economic terms. Thermal analysis is important to understand the evolution of the temperature in the building elements and also know the condition of the structure and its storage conditions. Other factors such as the location of the space, size of cooling chambers, working methodology, type of product stored, are key determinants in the energy efficiency of this type of structure. So, this study focuses on the characteristics of the envelope cooling chambers, where it studies the constructive solutions, particularly in terms of thermal bridges, the current leaks or damage to building elements, being the main theme in this work. The inside temperature of a refrigerated space will always have much lower temperature values than the surrounding outer space, so the thermal conduction in the frontage of the building cooling loads and heat gains by engaging are the main points analyzed. These parameters are important factors compared to energy consumption and maintenance costs of the refrigeration industry and THERM was the program used for calculating the thermal coefficients of several possible solutions tool. In this dissertation, is presented a case study of a building conservation of fish, and it was intended to find a suitable solution, applying alternatives to compare to the possible further improvements. Finally, it will be presented new proposals for future work about the refrigeration industry.

碩士
國立臺北科技大學
生產系統工程與管理研究所
90
Among the clustering methods, Ward’s+K-means method is the most frequently used due to its robustness(Sharma, 1996). Furthermore the algorithm correcting the shortcomings of observations which merging into the discomfort group can’t cluster anew in the hierarchical clustering methods. At the same time Ward’s+K-means method conquers the problem that the nonhierarchical clustering methods should determine the number of clusters in advance. Artificial neural networks (ANNs) have been, in recent year, successfully applied to a wide variety of business. A modified two stage method which first uses the self-organization feature maps (SOM) to determine the number of clusters and the starting points and then employs the K-means method to find the final solution (Kuo, 2001). However, in some cases, it is quite difficult to determine the cluster number by observing the outcome of network output array, unless the network topology is very clear. Grey system theory is applied to proceed relational analysis so as to confer and comprehend the indefinite model system in the incomplete information situation. (Wu, Deng ,and Wen, 1982). The research proposes a two-stage method ,which attempts to use grey relational clustering to determine the number and centroid of clusters and then employs the K-means method to find the final solution（it is defined as GRC+K）. Finally attempts to use Ward’s + K-means and SOM+K-means and GRC+K have been conducted through Monte Carlo Simulation data sets(Milligan, 1985). In order to further testify the proposed approach, a real-life problem, the refrigeration & air condition industry (RAC) is employed. The best clustering method that is evaluated by this research is used for planning the marketing strategy. It is expected to give the RAC industry a helping hand in distinguishing the major market segments, targeting one or more of those segments, and developing products and marketing programs tailored to each other.

Relatório de estágio do Mestrado Integrado em Engenharia Mecânica apresentado à Faculdade de Ciências e Tecnologia da Universidade de Coimbra
Os sistemas de refrigeração assumem uma cada vez maior importância na atual sociedade de consumo, sendo responsáveis por um enorme consumo energético. Na maior parte do tempo operam em carga térmica parcial, já que estes sistemas têm de ser projetados para conseguirem atender às condições de máxima carga de operação, ou seja, às condições nominais de projeto, correspondentes aos períodos mais exigentes. Consequentemente estes sistemas são habitualmente sobredimensionados para todas as condições de operação intermediárias e apresentam um consumo energético elevado. Num contexto de elevada competitividade industrial, associado à atual crise energética e ambiental, é imperativo reduzir os consumos de energia na operação dos sistemas de refrigeração. Atendendo a este facto, justifica-se o desenvolvimento e incorporação de componentes e tecnologias que promovam a melhoria do desempenho energético destas instalações. O objetivo deste trabalho, desenvolvido em paralelo com o estágio na empresa SKK, Climatização e Refrigeração, Lda., pretendeu caracterizar e identificar tecnologias e componentes para aumento do desempenho energético de sistemas de refrigeração. Tendo em conta o contexto de inserção na empresa e tipo de projetos nela realizados, apenas são abordados neste documento sistemas de refrigeração por compressão a vapor. Ao longo deste texto são analisados os principais parâmetros e componentes a verificar para o bom funcionamento de uma instalação frigorífica. É apresentado um estudo aos vários tipos de sistemas e equipamentos de controlo que promovem o desempenho energético de uma instalação frigorífica, e apresentadas as principais soluções existentes no mercado atual. São também descritas algumas das atividades executadas durante o estágio. Do estudo desenvolvido, conclui-se que o desempenho energético e eficiência de um sistema de refrigeração devem ser planeados e considerados nas várias fases de implementação do projeto. Atualmente, já existe no mercado um conjunto de tecnologias e componentes de controlo que promovem uma melhor eficiência e desempenho energético dos sistemas de refrigeração, contribuindo, assim, para a redução dos custos energéticos e ambientais.
As time goes by refrigeration systems have been getting an even greater importance in today’s society, and are responsible for a great energy consumption. Most of the time these systems operate at partial load, since they have to be projected to deal with the maximum needed load conditions for the harshest periods of operation. Therefore, these systems are oversized for all intermediary operating states resulting in a high energy consumption. In a high competitive industrial context, in association with the nowadays energetic and environmental crisis, it is imperative do reduce the operations costs related to the energy bill. So, it is of the outmost importance the development and implantation of components and technologies that promote the energetic performance and efficiency of these systems. This thesis’s goal, developed side by side with an internship at SKK, Climatização e Refrigeração, Lda, it’s the study of technologies and components that promote a better energetic performance of refrigeration systems. Having into account the company’s insertion context and the type of projects that are developed there, only vapor compressing systems will be referred to. During this document several items and parameters are verified and analyzed to achieve a good and functioning refrigeration plant. Various types of control systems and control equipment for a refrigeration plant are presented, as well as the existing solutions for their retrofitting. Some activities performed during the internship are also referred to. From the study developed it is concluded that the energetic performance and efficiency of a refrigeration system must be planned and considered on all the phases of the project’s implementation. At this moment, it is already available in the market a fair amount of technologies and control components that promote a greater efficiency and energetic performance of these systems, therefore contributing to the reduction of the operation costs and environmental impacts that are associated with these systems.

Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e Tecnologia
O presente documento reporta o trabalho de investigação feito durante um estágio realizado no Instituto de Soldadura e Qualidade (ISQ), no âmbito do projeto EcoTermIP. Este projeto tem o objetivo de promover a eficiência energética em vários setores da indústria entres os quais o setor alimentar da carne (Indústrias de preparação de carne e produtos à base de carne). Nesse contexto, o estudo realizado foca-se na eficiência energética térmica, nomeadamente nos sistemas de refrigeração, essenciais para as empresas do setor mencionado.O modus operandi seguido resumiu-se, numa primeira fase, à revisão bibliográfica de literatura relacionada com refrigeração e geração de vapor usadas na indústria das carnes, que permitiu não só recolher valiosas informações acerca dos equipamentos e processos envolvidos, mas também perceber as medidas comummente usadas para tornar os processos eficientes. Seguidamente, realizaram-se várias visitas a empresas de processamento, conserva e/ou distribuição de carne. Desta forma, foram recolhidos dados úteis para, após o devido tratamento, poderem ser usados para suportar as medidas aplicadas.De entre as medidas presentes na bibliografia, quatro foram selecionadas e estudadas no âmbito da atividade de duas empresas do sector. Desta forma, o objetivo seria perceber se as medidas eram viáveis, não só do ponto de vista da eficiência energética térmica, mas também do ponto de vista económico. a obter resultados que indicassem se as medidas deviam ou não ser Os resultados obtidos foram satisfatórios, com especial enfoque para as medidas de instalação de um permutador após a torre de refrigeração e da otimização da pressão de descarga do compressor que resultaram em poupanças na ordem dos 10000 €.Foram também identificadas oportunidades de trabalho futuro, abrindo portas para novas investigações ou estudos mais específicos sobre os tópicos abordados.
The present document accounts for the investigative work carried out during an internship held at the Instituto de Soldadura e Qualidade (ISQ), inserted in the project EcoTermIP. This project aims at promoting energetic efficiency in various industrial sectors amongst which the food production, more specifically the meat industry (factories that prepare and/or process meat and meat-based products). In this context, the present study focuses on the thermal energetic efficiency, namely on the refrigeration systems essential for companies of the above-mentioned field. In the initial stage, the modus operandi was to conduct a bibliographic review of literature related to refrigeration and the generation of steam used in the meat industry. This approach allowed not only the collection of valuable information about the equipment and processes involved but also a better understanding of the measures commonly undertaken to make the processes efficient. Hereafter, several visits followed to companies that deal with meat processing, meat canning and/or meat distribution. Thus, very useful data were gathered, which after being analyzed in detail, could be used to back up the implemented measures. From all the measures present in the bibliography, four were selected and studied within the ambit of the activity of two companies operating in this sector. The aim was to understand if the measures adopted were viable not only in regard to the thermal energetic efficiency but also in a budgetary sense The results achieved were very acceptable, the principal focus being the plans to install a desuperheater and the optimization of the compressor’s discharge pressure which resulted in annual savings of around 10000 €.Opportunities for future work were also identified, opening doors to new investigations and further studies on the subjects here discussed.

The increasing price of oil and the destabilisation of the world’s climate are urging governments, businesses and individuals to constantly investigate energy-efficient technologies and methodologies and pursue the adoption of energy efficiency programmes in a global effort to reduce energy consumption, greenhouse gas emissions and ultimately energy costs. In New Zealand, one of the biggest industrial energy efficiency projects was started in 2002 by a multinational dairy company, the Fonterra Co-operative Group, in partnership with the energy service company Demand Response Ltd; the project currently aims at reducing by 15% the energy costs at all Fonterra’s major production sites throughout the country. This thesis, undertaken as part of the above project, examines the development and implementation of a structured and integrated energy monitoring and targeting methodology (M&T) for the most efficient operation of all Fonterra’s chilled water systems, with an initial focus on the ones installed at Clandeboye, one of the Fonterra’s sites involved in the energy saving project. A data collection system (Insite) was already in place at Clandeboye to enable storage and analysis of some of the site’s utility metering data. After identification of key chilled water system components and definition of data requirements for M&T purposes, an analysis of past energy consumption trends (based on multiple regression calculations) was carried out to develop an historical benchmark of the energy used, compare it with current energy performance and thus identify opportunities for future improvements. The creation of an M&T reporting system for presenting findings to operators and management was the last essential part of the thesis development. The study has highlighted that the robustness of the proposed regression model was badly affected by the unreliability of the existing data collection system and the uncertainty associated with poorly documented changes to operating conditions/plant configuration that had occurred over time. The conclusion is that, while the developed M&T methodology is theoretically valid and readily applicable, further developments are necessary (and recommended) to make it suitable for other similar systems.

碩士
東海大學
企業管理學系碩士班
101
These years the climate is dramatically fluctuating. There are some extreme and abnormal phenomena, for example Greenhouse Effect which have cause problems to human beings. States have to face the elements which cause the human harming phenomena. As a member of the mother earth, every single unit has to do her obligation. 　The Low-Carbon Economy era is coming; states are focus on the sustainable development and environmental protection. If Taiwan wants to play an important role in nowadays highly competitive international society, she must be done to protect the environment, sustainable use the resources, and reduce carbon dioxide emissions. The development of energy-saving technology industry was born in the time of the need. Furthermore, it will be one of the most important issues to upgrade technology and equipment of the energy-saving technology industry, and train more required talents. In this way, Taiwan is more likely to become one of the important members of the international economy. 　For the above reasons, we do the study about technical talent of the energy-saving technology industry. We use Analytic Hierarchy Process（AHP） based on Spencer, LM & Spencer, SM’s iceberg model. We want to identify the competence and the relative importance of each item of green refrigeration & air-conditioning and Light-Emitting Diode. There are five areas of them: motives, traits, self-concept, knowledge and skills. By doing the research we want to find out a reference for the recruitment and training of the human resources department of the energy-saving technology industries. 　According to the results of the two industries, we could get the following conclusions: In green refrigeration & air-conditioning industry, the most important item of each fields of competence are "self-realization and affirmation", "spirit", "ethics", "frozen engineering principles" and "energy-saving of green refrigeration & air-conditioning system and innovative technology". Among the five fields, "traits" is the most important. In the part of the Light-Emitting Diode industry, the most important item of each fields of competence are "the driving force of the social environment", "high resistance to stress and self-management", "the teamwork practices", "advanced core subject curriculum", and "technology application ability". Among the five fields, "skills" is the most important.