The Role of “Allowable Flux Density” in the Design and Operation of Molten-Salt Solar Central Receivers

2001 ◽  
Author(s):  
Lorin L. Vant-Hull
Keyword(s):  
Molten Salt ◽  
Flux Density ◽  
Thermal Power ◽  
Cost Effective ◽  
Temperature Dependent ◽  
The North ◽  
Effective Manner ◽  
Computer Codes ◽  
Commercial Applications

Abstract In the 1980’s, the Utility Study [Hilesland and Harder, 1988] identified the external cylindrical molten-salt-in-tube receiver with a surround heliostat field as the most cost effective and practical design for commercial applications. Such designs typically require 50–1000 MW of design-point thermal power at outlet temperatures around 1050 °F (565 °C). Using computer codes such as RCELL [Lipps and Vant-Hull, 1981] or DELSOL [Kistler, 1987] it is straightforward to design an optical system to meet these requirements, defining the smallest receiver (lower cost and thermal losses) and the most cost effective heliostat field. As the performance of heliostats in the anti-sun locations is better, such fields tend to be biased (in the northern hemisphere) to the north side of the receiver, and produce very high flux densities there; typically 2–5 MW/m2. However, the receiver is typicaly limited to a salt velocity and temperature dependent allowable flux density (AFD) of about 1 MW/m2. Design methods to reduce this peak flux to a nominally acceptable value in a cost effective manner are presented. Residual excess flux events under non-nominal conditions are handled by a real-time processor which selects specific heliostats for removal from track. This same processor is used to preheat the receiver, using a special algorithm to define the required flux density.

The Role of “Allowable Flux Density” in the Design and Operation of Molten-Salt Solar Central Receivers

2002 ◽  
Vol 124 (2) ◽  
pp. 165-169 ◽  
Author(s):  
Lorin L. Vant-Hull
Keyword(s):  
Molten Salt ◽  
Flux Density ◽  
Thermal Power ◽  
Cost Effective ◽  
Santa Fe ◽  
The North ◽  
Effective Manner ◽  
Computer Codes ◽  
Commercial Applications

In the 1980s, the Utility Study [Hilesland, T., Jr., and Weber, E. R., 1988, “Utilities’ Study of Solar Central Receivers,” Fourth Int. Symp. on Research, Development, and Applications of Solar Thermal Technology, Santa Fe, NM] identified the external cylindrical molten-salt-in-tube receiver with a surround heliostat field as the most cost effective and practical design for commercial applications. Such designs typically require 50–1000 MW of design-point thermal power at outlet temperatures around 1050°F (565°C). Using computer codes such as RCELL [Lipps, F. W., and Vant-Hull, L. L., 1978, “A Cellwise Method for the Optimization of Large Central Receiver Systems,” Solar Energy, 20(6) pp. 505–516.] or DELSOL [Kistler, B. L., “A Users Manual for Delsol 3,” Sandia National Laboratories Livermore, SAND86-8018, 1987.] it is straightforward to design an optical system to meet these requirements, defining the smallest receiver (lower cost and thermal losses) and the most cost effective heliostat field. As the performance of heliostats in the anti-sun locations is better, such fields tend to be biased (in the northern hemisphere) to the north side of the receiver, and produce very high flux densities there; typically 2–5 MW/m2. However, the receiver is typicaly limited to a salt velocity and temperature dependent allowable flux density (AFD) of about 1 MW/m2. Design methods to reduce this peak flux to a nominally acceptable value in a cost effective manner are presented. Residual excess flux events under non-nominal conditions are handled by a real-time processor which selects specific heliostats for removal from track. This same processor is used to preheat the receiver, using a special algorithm to define the required flux density.

scholarly journals The Technological Growth in eHealth Services

2015 ◽  
Vol 2015 ◽  
pp. 1-18 ◽  
Author(s):  
Shilpa Srivastava ◽  
Millie Pant ◽  
Ajith Abraham ◽  
Namrata Agrawal
Keyword(s):  
Health Services ◽  
Communication Technology ◽  
Cost Effective ◽  
Information Communication ◽  
Geographic Boundaries ◽  
Effective Manner ◽  
Technological Growth ◽  
Medical Benefits ◽  
Ehealth Services

The infusion of information communication technology (ICT) into health services is emerging as an active area of research. It has several advantages but perhaps the most important one is providing medical benefits to one and all irrespective of geographic boundaries in a cost effective manner, providing global expertise and holistic services, in a time bound manner. This paper provides a systematic review of technological growth in eHealth services. The present study reviews and analyzes the role of four important technologies, namely, satellite, internet, mobile, and cloud for providing health services.

Role of Prophylactic Knee and Ankle Bracing in Injury Reduction

1992 ◽  
Vol 1 (3) ◽  
pp. 223-236 ◽  
Author(s):  
Michael R. Sitler
Keyword(s):  
Clinical Research ◽  
Knee Injuries ◽  
Cost Effective ◽  
Ankle Injuries ◽  
Injury Reduction ◽  
Recent Approach ◽  
Effective Manner ◽  
Confounding Variables ◽  
Research Analysis

Knee and ankle injuries continue to be ever present at all levels of athletic participation. A relatively recent approach in injury intervention is the use of prophylactic knee braces (PKB) and ankle stabilizers (AS). Prophylactic braces are used to reduce the frequency and severity of injuries in a cost effective manner, but their clinical efficacy has been questioned. Specific to PKB, there is little agreement among the results of studies completed to date as to their effectiveness in reducing the incidence of knee injuries. This is attributed to a lack of control of confounding variables that mitigate the interpretive findings of many studies. Although the clinical research regarding AS is limited, it appears that they are effective in reducing the incidence of acute ankle injuries. Recommendations for future study as well as considerations for clinical research analysis are presented.

scholarly journals The Importance of Collaboration and Competition Within and Outside the OECD

2016 ◽  
Vol 11 (9) ◽  
pp. 13
Author(s):  
Ian Jackson ◽  
John McManus
Keyword(s):  
Global Economy ◽  
Cost Effective ◽  
World Market ◽  
Global Market ◽  
Conceptual Approach ◽  
Global Marketplace ◽  
Effective Manner ◽  
Challenges And Opportunities ◽  
National Governments

The purpose of this paper is to address the role of the OECD in the global marketplace. The paper highlights some current trends in the global market and the changing role of the OECD. In this context, the authors discuss various perspectives on the role of OECD in a globalized world. The authors focus on recent debates on the state of the global economy and the changing position of the OECD in the world market. The authors apply a conceptual approach combined with analyses of data and secondary material. The authors also put forward an argument for investigating what determines competition within and outside the OECD. In this context, creating markets within a global economy requires considerable stimulus on the part of national governments. This necessitates national governments working together in partnership with national and global firms to reduced bureaucracy and increase transparency to boost trade in a cost effective manner. This is seen by some economists to be a prerequisite to future competitiveness. Finally, the authors seek to demonstrate how leading countries within the OECD are building innovative capability to master the challenges and opportunities that the new emerging economies present (such as Brazil).

Restoring Technical Potential of Deep-Water Well Impaired by Hydrate Plug Embedded with Wax Deposit with Improved Characterization and Innovative Chemistry

2021 ◽  
Author(s):  
Anwarudin Saidu Mohamed ◽  
Syafiq Effendi Jalis ◽  
Intiran Raman ◽  
Kumanan Sanmugam ◽  
Dhanaraj Turunawarasu ◽  
...  
Keyword(s):  
Melting Point ◽  
Deep Water ◽  
Cost Effective ◽  
Chemical System ◽  
Positive Pressure ◽  
Fluid Temperature ◽  
Temperature Dependent ◽  
Capillary Tubing ◽  
Effective Manner

Abstract Hydrate occurrence is synonymous in deep water wells, notably when the well experience significant reduction in fluid temperature during production. Hence, the operating philosophy must take into consideration the ability to maintain the well-fluid outside the hydrate or wax phase envelope and ensure the contingencies are in place to mitigate any plug, deposit or gel formation. This paper illustrates the characterization of hydrate and wax plug encountered and devise of innovative solution to remediate the blockage in two wells in Sabah waters which were plugged due to cooling of the wells during an unplanned shut down. The solution devised is to set precedence to manage temperature dependent blockages in similar Deepwater wells or facilities. Hydrate and wax models were created to predict blockage severity and its location. Nodal analysis was used to model thermodynamic equilibrium at target location of the plug where the temperature is below the melting point and ultimately to predict the required heat to dissolve the blockages. A Thermo-chemical system was identified, selected, and customized and then injected into well to ensure the temperature generated at the location of the plug was above the melting point of hydrate and wax. Thermo-chemical injection was identified as a viable method of In-situ Heat Generating Technique to generate heat at desired location. The chemical solution was injected via capillary tubing to transmit the heat via conduction and convection to melt the hydrate and paraffinic plug in these 2 wells. An arriving temperature of 40°C at the target zones was required to melt the plug. A positive pressure was maintained in the production tubing during chemical injection to avoid rapid pressure increase as the hydrate plugs dissolved. A temperature of 100 °C was recorded at the wellhead throughout the injection. The downhole gauge indicated positive response, suggesting the heat generated transmitted effectively. After a short duration of injection, communication was established. Hydrate inhibitor was injected to secure the well prior to unloading. The wells were successfully relieved and stabilized production of 1,200 bopd and 800 bopd respectively. The simulation was redesigned based on data collected from the operation to improve the model and to be used for future works. The ability to integrate laboratory analysis, computer aided simulation and operational data was integral to this paper demonstrating an effective way to characterize temperature dependent blockages in production system. Design of experiments provided better insight to address the problem. Innovative use of novel chemistry to produce heat, in-situ heat solved hydrate and wax related issues in a most cost-effective manner. The process of customizing a chemical system based on laboratory and simulation results was effective in ensuring delivery of the results. The bull-heading operation to inject the chemical system proved to be a cost-effective remedial method to unlock the barrels and can be considered preventive or as a contingency measure in dealing with temperature dependent blockages or plugs in future.

scholarly journals Going offshore or not: Where to generate hydrogen in future integrated energy systems?

2021 ◽  
Author(s):  
Juan Gea Bermúdez ◽  
Matti Juhani Koivisto ◽  
Lena Kitzing ◽  
Andrés Ramos ◽  
Rasmus Bo Bramstoft Pedersen
Keyword(s):  
Hydrogen Generation ◽  
Cost Effective ◽  
Energy System ◽  
Offshore Wind ◽  
Solar Pv ◽  
Integrated Energy Systems ◽  
The North ◽  
Integrated Energy System ◽  
Pv Generation

Hydrogen can be key in the energy system transition. We investigate the role of offshore hydrogen generation in a future integrated energy system, and its interaction with other system elements. By performing energy system optimisation in a model application of the Northern-central European energy system and the North Sea offshore grid towards 2050, we find that offshore hydrogen generation may likely only play a limited role, and that offshore wind energy has higher value when sent to shore in the form of electricity. Forcing all hydrogen generation offshore would lead to increased energy system costs (9-28 b\EUR2016/year by 2045). Under the assumed scenario conditions, hydrogen generation - both onshore and offshore - follows solar PV generation patterns. Combined with hydrogen storage, this is the most cost-effective solution to satisfy future hydrogen demand. Overall, we find that the role of future offshore hydrogen generation should not simply be derived from minimizing costs for the offshore sub-system, but by also considering the value that such generation would create for the whole integrated energy system. Based on our results, a stronger political effort to promote the integration of offshore wind in onshore energy markets via electrical connection is called for.

scholarly journals Investigating Tendencies of Malaysian Muslims in Islamic Estate Planning: Insight into Its Determinants

2021 ◽  
Author(s):  
Norazlina Abd Wahab ◽  
Selamah Maamor ◽  
Suraiya Hashim ◽  
Zairy Zainol ◽  
Hakimah Yaacob
Keyword(s):  
Structural Equation ◽  
Cost Effective ◽  
Peninsular Malaysia ◽  
Estate Planning ◽  
Management Planning ◽  
The Public ◽  
Equation Modelling ◽  
Effective Manner ◽  
Insight Into

Estate planning is one of the crucial elements of managing property during a person’s lifetime. It involves both handling and managing property during one’s lifetime and after death. For Muslims, the objectives of Shariah, which are known as Maqasid Shariah, can be attained if their finances are planned in a wise and cost-effective manner. Unfortunately, it was reported that frozen inheritance assets have steadily increased from the day of Independence, amounting to RM70 billion in 2020 indicating the seriousness of the matter. The freezing of inheritance property is detrimental to the economy and thus opposes the spirit of  Maqasid Shari’ah which recommends that it should be properly managed for the benefit of the public. This is where estate planning plays its role in ensuring quicker and easier distribution of assets and property. Hence, the objective of this research is to investigate Malaysian Muslims’ tendencies in estate management planning and its determinants. A total of 406 respondents throughout Peninsular Malaysia responded to the prepared survey, where the Partial Least Squares Structural Equation Modelling (PLS-SEM) approach was employed as the main data analysis for this study. The findings revealed that altruism, advantages and compliance were significant in influencing tendencies of Malaysian Muslims in Islamic estate planning. Surprisingly, service was found to be an insignificant factor in influencing the tendencies of Malaysian Muslims in Islamic estate planning. This study provides some insights on the role of policymakers and estate planning related industry in ensuring the compliance of estate planning product and increasing the awareness of Muslims to do estate planning by promoting the advantages and importance of doing so. Policymakers are also welcome to engage in this matter by providing earlier education on Islamic estate planning among Muslims in Malaysia.  

Fluorescence application to hydrocarbon monitoring in North West Shelf marine waters

2015 ◽  
Vol 55 (1) ◽  
pp. 345
Author(s):  
Felicity Harrison ◽  
Riley McAuliffe ◽  
Jose Romero ◽  
Keith Stubbs ◽  
Carolyn Oldham
Keyword(s):  
Standard Procedure ◽  
Cost Effective ◽  
Temporal Variations ◽  
Fluorescent Properties ◽  
Marine Waters ◽  
North West ◽  
Hydrocarbon Detection ◽  
Background Fluorescence ◽  
The North ◽  
Effective Manner

The application of fluorometry to hydrocarbon detection in marine waters is a standard procedure in many parts of the world. This technology is advantageous because spatial and temporal variations in hydrocarbon distributions can be acquired readily and rapidly in a cost-effective manner compared to traditional sampling methods. Its application to North West Shelf marine waters has been examined through two recent research studies. In the first study, the fluorescent properties of North West Shelf hydrocarbons were compared to those from North America. In general, peak fluorescence of North West Shelf samples are lower than North American and European hydrocarbons. Hence, fluorometer specifications (e.g. excitation and emission wavelengths) need to be tailored for hydrocarbon detection within North West Shelf waters. The second study measured low background fluorescence of a representative region of the North West Shelf using the fluorometer specifications recommended in the first study. This indicates that background fluorescence is unlikely to affect hydrocarbon detection in the marine waters of the North West Shelf. These studies support the use of fluorometry as a technique to reliably detect and to monitor unplanned (e.g. spills) and planned (e.g. producted formation water) hydrocarbon discharges across the North West Shelf.

The Revision of the European Union’s Emissions Trading System Ahead of the Fourth Trading Period, 2021–2030

Climate Law ◽  
2018 ◽  
Vol 8 (3-4) ◽  
pp. 338-348 ◽  
Author(s):  
Joshua Prentice
Keyword(s):  
Emissions Trading ◽  
Decisive Role ◽  
Cost Effective ◽  
Eu Ets ◽  
The European Union ◽  
Trading System ◽  
Effective Manner ◽  
Trading Period ◽  
Final Agreement

The EU ETS is the cornerstone of the European Union’s climate policy. The EU ETS will play a decisive role in the European Union plan to meet its commitments under the Paris Agreement. In November 2017, following more than two years of negotiations, EU member states and the European Parliament reached a final agreement on the revision of the EU ETS for the period 2021–2030. The final agreement struck an important, ambitious balance on a number of measures designed to ensure that the EU ETS achieves its legislative aims of promoting emission reductions in a cost-effective manner. The negotiations also provide a number of policy lessons for future negotiations relating to the role of EU institutions and the rules for free allocation which will be important for the EU ETS to meet its legislative objectives. 1

scholarly journals Az alapanyagkészlet csökkentésére irányuló folyamatok bemutatása az ellátási láncban

2017 ◽  
Vol 16 (4) ◽  
pp. 61
Author(s):  
Judit Dr. Oláh ◽  
Péter Balogh ◽  
Zoltán Lakner ◽  
József Popp
Keyword(s):  
Raw Materials ◽  
Cost Effective ◽  
Future Application ◽  
Inventory Level ◽  
Vendor Managed Inventory ◽  
The North ◽  
Role Of Information ◽  
Minimize Costs

Minden termelő szervezet törekszik arra, hogy folyamatait minél gazdaságosabb módon végezze a kiadások csökkentése és a profit maximalizálása érdekében. Az egyik fő irány a kiadások csökkentése céljából a készletérték minél alacsonyabb szinten tartása. Ennek eléréséhez több folyamatot is működtet a vizsgált vállalat, nevezetesen az úgynevezett beszállítók által vezérelt raktárkészlet ellenőrzési folyamatot (Vendor Managed Inventory –VMI), amikor a beszállító kezeli a vállalat készleteit és a konszignációs eljárást, ahol a beszállító kihelyezi a gyár területére a készletet. Ennek a két eljárásnak a bemutatása és elemzése a kutatásunk célja. Arra a kérdésre keresünk választ, hogy ezek alkalmazásával valóban csökken-e a készletben lekötött tőke a vizsgált vállalat számára, és ha igen, akkor milyen mértékben? További kérdés, hogy elégséges-e a készletben lekötött tőkecsökkentés szintje ahhoz, hogy ezeket a jövőben is alkalmazzák vagy újra bevezessék? A kutatást esettanulmány jelleggel valósítottuk meg az Észak-alföldi régióban található termelő vállalatnál figyelembe véve az információs technológiai rendszerek szerepét. --- Processes to Minimize Raw Materials Inventory Level in the Supply Chain Producers are eager to implement their processes more effectively in order to minimize costs and to maximize profit. The primary purpose is to keep inventory value at the lowest possible rate to minimize costs. To this end, the investigated organization operates several processes. One of them is the so-called Vendor Managed Inventory (VMI), in which the supplier manages the inventory of the customer and the second is the consignment inventory processing, in which suppliers store goods at the customer location. The principal goal of this paper is to examine whether the application of these methods may result in cost-effective savings for the examined organization and if yes, to what extent. Is the level of cost saving sufficient to enable future application or re-introduction? Research was carried out within the framework of a case study at a producing organization in the North-Great Plain Region taking into consideration the role of information technology systems.

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