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[en] The antenna of the KSTAR ICRF heating system was newly fabricated, which has many enhanced aspects in comparison with the prototype antenna. RF test for the modified antenna was performed without any cooling of the antenna during RF test campaign-5. The maximum standoff voltage was estimated through the RF tests and antenna performance was tested during 300-sec long pulse test. A bottom half of the current strap-1 was connected to the test section with an electrical length of 20 m which is equal to two times of the wave length at a frequency of 30 MHz. So a standing wave was generated on the test section. As a result, the maximum standoff voltage was 40.0 kVp at a pulse length of 5 sec. It was limited by a breakdown on the teflon insulator used in transmission line. Long pulse test showed the maximum standoff voltage was 24.3 kVp at a pulse length of 300 sec. It was limited by overheating of the antenna. It was confirmed that it is impossible to increase available voltage at 300-sec long pulse operation without any cooling. It means that active cooling of the antenna is necessary to increase the standoff voltage. During this test campaign, a range of multifactor discharge was experimentally determined, and conditioning effect was estimated
[en] Coal-condensing power is marginal production in the deregulated Nordic power market and an increase in electricity consumption will therefore result in increased CO2 emissions. One goal of the Swedish energy policy is to reduce the amount of electricity used for heating in the building sector. This paper investigates the potential for reduction in electricity dependency and CO2 emissions from heating, taking the energy infrastructure into account, here defined as the capital stock of the buildings and heating systems together with geographical variations in heat intensity. In order to include the energy infrastructure in the analysis the study is made on a regional level (Southern Sweden) applying a comprehensive database describing the energy infrastructure of the region. The paper compares two scenarios for converting the heating systems of the region: one employing energy savings and with the aim to phase out the oil and most of the electricity used for heating purposes and a second which illustrates the effect if the current trend in the heating market continues. Both scenarios apply commercially available technologies only. From the second scenario it is seen that the current trend-contrary to the aim of the Swedish Governmental policy-shows an increase in electricity dependency for heating, mainly due to a large diffusion of heat pumps, but also due to installations of electrical floor heating and electricity heating systems installed in newly constructed one- and two-dwelling buildings. However, the options proposed in first scenario show that it is possible to reach significant reductions in the electricity dependency due to heating and in corresponding CO2 emissions. An analysis of the age structure of the heating systems shows that the transformation of the heating system is not completed until the year 2025, if new investments for replacement of heating systems are made only provided they have reached their economical life time, and only applying heating technologies which at present are known to be economically competitive. It can be concluded that future policies on transforming the energy system should be based on an analysis that takes the entire energy infrastructure (in this case of heating system) into account (e.g. not directed towards single technologies). More specifically for the region studied, which is considered representative for Sweden as a whole, policies should aim at installing heat pumps to replace electricity heating only in regions with low heat density where district heating is not competitive, in contrary to the present situation where heat pumps replace all types of heating systems
[en] This report is based on a previous, related, one which was quantitative in character and relied on 500 telephone interviews with house-owners. The aim of this, following, report was to carry out a more deep-going, qualitative analysis focussed on persons who already own a solar heating system (purchased during 1992) or were/are considering having one installed. Aspects studied were the attitudes, behaviour and plans of these two groups with regard to solar heating systems. Some of the key questions asked concerned general attitudes to energy supply, advantages and disadvantages of using solar heating systems, related decision-making factors, installation problems, positive and negative expectations, evaluation of the information situation, suggestions related to information systems regarding themes etc., dissemination of information, sources of advice and information, economical considerations, satisfaction with the currently-owned system which would lead to the installation of another one in connection with the purchase of a new house. The results of this investigation directed at Danish house-owners are presented and discussed, and proposals for following activities within the marketing situation are given. It is concluded that the basic attitude in both groups strongly supports environmental protection, renewable energy sources and is influenced by considerations of prestige and independence. Constraint factors are confusion about environmental factors, insecurity in relation to the effect of established supplementary energy supply and suspicion with regard to the integrity of information received. (AB)
[en] Jordan is relatively poor in conventional energy resources and is basically a non-oil producing country, i.e. its energy supply relies to a very large extent on imports. It is therefore unlikely that any future energy scenario for Jordan will not include a significant proportion of its energy to come from renewable sources such as solar energy. The lack of an integrated energy saving system which utilizes the solar energy for domestic hot water as well as for building space heating was the main motivation for the present study. In Jordan, there is no existing system can provide the integration mechanisms of solar energy and fuel combustion with electrical ones. Also adding new and related products increases sales of current boilers products and can be offered at competitive prices. During our investigations, it has been found that the market demand for boiler-solar integration system in terms of the system acceptability, system feasibility, and system values is very high especially after the increased in oil prices during the last 3 years, i.e. 2006-2008. The market trend shows that even though solar collector is not attractive as an energy source for domestic hot water, but the combined system for space heating and domestic hot water is fully accepted. However, the market demand for such a system is not completely identified yet but the awareness and the discussion of the idea shows a good potential. The economical study about the integration system of boiler and solar energy shows that using solar water heaters to heat space and for domestic water is cost-effective. Payback can be as low as 3 years, and utility bills are much lower than they would be using a conventional heating system. The initial draft and design of a prototype for the boiler-solar-electrical integration system has been carried out. (author)
[en] This article discusses the development of the use of solar collectors over their past 30 years of history and describes today's state-of-the-art for solar installations that are used for hot water preparation and space heating. Advances made in storage technology, in the dimensioning of installations and in the operation of the systems are discussed in detail. The importance of low-flow operation for hot water installations is emphasised. Also, the integration of solar and conventional heating systems is looked at and questions regarding further factors such as those encountered in low-energy-consumption buildings are discussed. Future developments in the product and market areas are looked at, including new forms of storage as well as solar cooling and air-conditioning
[en] Cyclotron CS-30 is a charged particle accelerator owned by BATAN. One of the requirements for the operation is moisture condition (humidity) in the Cyclotron Cave which should be below 55 %. Damage of the heating system (duct heater) makes the humidity rises above the limit value. To overcome these problems modifications have been made to the duct heater control with the aim of reviving the heating system and maintaining the reliability of the heating system so that stability of humidity can be achieved. The methodology used here is by to utilizing the incoming air flow of the VAC system as an indication to control the operation of the heating system. Therefore an air flow-based control unit has been built that can operate the heating system so that the stability of the humidity in the Cyclotron Cave can be achieved. (author)
[en] The presence of flavored olive oils (FOO) on the market represents an answer to an increasing consumer demand for novel and healthy food. This work aims to compare the sensory acceptability and the thermal stability of FOO prepared by mixing different flavors (lemon, onion, garlic, paprika) to an extra virgin olive oil (EVOO) also used as the control sample. 96 Tunisian citizens were involved in a consumer test and the lemon flavored oil was the most liked whereas the least liked was the oil with onion. Samples were subjected to different heat treatments (60 °C, 100 °C, 200 °C for 1, 2, 4, 8 hours) and the flavor addition did not influence the EVOO stability when samples were heated at 60 °C, whereas at 200 °C the FOO with onion and garlic showed higher oxidative stability. The thermo-oxidation process at 60 °C and at 100 °C of the FOOs was not detrimental for the volatile compound markers but the effect was noticeable for all these markers at 200 °C.
[es]La presencia de aceites de oliva con sabor (FOO) en el mercado representa una respuesta a la demanda cada vez mayor de los consumidores de alimentos novedosos y saludables. Este trabajo tiene como objetivo comparar la aceptabilidad sensorial y la estabilidad térmica de FOO preparado mediante la mezcla de diferentes sabores (limón, cebolla, ajo, pimentón) a un aceite de oliva virgen extra (AOVE), utilizado como muestra de control. 96 ciudadanos tunecinos participaron en una prueba de consumo: el aceite con sabor a limón fue el que más gustó, mientras que el que menos gustó fue el de la cebolla. Las muestras se sometieron a diferentes tratamientos térmicos (60 °C, 100 °C y 200 °C durante 1, 2, 4, 8 horas). La adición de saborizantes no influyó en la estabilidad del AOVE cuando las muestras se calentaron a 60 ° C mientras que a 200 °C el FOO con cebolla y ajo mostraron una mayor estabilidad oxidativa. El proceso de termooxidación a 60 °C y a 100 °C de los FOO no fue perjudicial para el marcador de compuestos volátiles, en oposición al efecto a 200 °C que resultó notable para todos estos marcadores.
[en] The objective of the project is to develop and improve large procurements of solar heating systems in order to be able to place large orders with manufacturers and suppliers. The project work will be carried out as an international co-operation under IEA Task 24 with the title 'Solar Procurement'. By co-ordinating the effort between the 4-6 participating countries, the objective is to purchase at least 10,000 solar heating systems, of this amount 1,000-2,000 in Denmark. Such large orders make it possible for manufacturers and suppliers to deliver systems considerably cheaper, and it will be possible to develop systems for given specifications on output and efficiency. These co-ordinated large orders are expected to improve the price/efficiency conditions by up to 50%. The so called 'procurement process' (co-ordinated international procurement based on goal-oriented system development in co-operation between customers and suppliers/manufacturers) will in the project be followed up by information/marketing, education, financing schemes, service schemes, quality assurance and technical support. The project is divided into two main areas (IEA subtasks). 1: 'Procurement and Marketing' and 2: 'Creation of Tools'. Denmark has been requested to be the project manager of subtask 2, 'Creation of Tools'. (EHS)
[en] A new solar collection system integrated on the façade of a building is investigated for Dutch climate conditions. The solar collection system includes a solar façade, a receiver tube and 10 Fresnel lenses. The Fresnel lenses Fresnel lenses considered were linear, non-imaging, line – focused with a system tracking the position of the sun that ensures vertical incidence of the direct solar radiation on the lenses. For the heating system a double-effect absorption heat pump, which requires high temperature of the heating fluid, was used, working with water and lithium-bromide as refrigerant and solution respectively. The Fresnel lens system is connected with the absorption heat pump through a thermal energy storage tank which accumulates the heat from the Fresnel lens system to provide it to the high pressure generator of the absorption heat pump. - Highlights: • The integration of Fresnel lenses in solar thermal building façades is investigated. • Using building integrated Fresnel lenses, 43% heating energy can be saved. • Energy savings in Mediterranean countries are significantly larger. • The absorption heat pump could make great contribution to energy savings for Dutch climate conditions
[en] The purpose of this article is to assess the value of entransy for use in the thermal system engineering domain and in particular for design. The conclusion is that use of entransy is not recommended. This finding is in keeping with increasing uneasiness that has emerged recently in the technical literature about this concept. Throughout this article emphasis is on concise discussions of salient entransy aspects and the presentation is shaped to reach a broad technical audience. Accordingly, because secondary entransy aspects do not play a central role in reaching the above recommendation, they are considered only in passing or deferred. - Highlights: • A methodology for analysis, design, and optimization of thermal systems. • Entransy is not recommended for use in thermal system engineering. • Components of actual thermal systems do not operate ideally on any basis. • Entropy and exergy rest firmly on the second law of thermodynamics. • Entransy arises by analogy