scholarly journals Modeling and experimental evaluation of a small-scale fresnel solar concentrator system

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Luis Rafael Sanchez Vega
Keyword(s):  
Experimental Evaluation ◽  
Small Scale ◽  
Solar Concentrator

Economical and Environmental Aspects of the Microturbine’s Application in Brazil

2002 ◽  
Author(s):  
Eli Eber Batista Gomes ◽  
Vladimir Rafael Melian Cobas ◽  
Marco Antoˆnio Rosa do Nascimento ◽  
Electo Eduardo Silva Lora
Keyword(s):  
Natural Gas ◽  
Distributed Generation ◽  
Experimental Evaluation ◽  
Minas Gerais ◽  
Small Scale ◽  
Study Group ◽  
Environmental Aspects ◽  
Thermal Systems ◽  
The Future ◽  
The Cost

Microturbine generators have shown good perspectives for small scale distributed generation. In Brazil, the Thermal Systems Study Group of Federal School of Engineering of Itajuba´, sponsored by the CEMIG (Electrical Utility of Minas Gerais), is developing a project about experimental evaluation of microturbines systems. The objective of this paper is to evaluate the cost of generating electricity with microturbines and show the emissions range of microturbines operating with natural gas. The cost of the microturbine generators as well as the cost of the electricity and natural gas in Brazil at this moment and the projection for the future were considered.

An experimental evaluation of powder flow predictions in small-scale process equipment based on Jenike's hopper design methodology

2017 ◽  
Vol 321 ◽  
pp. 523-532 ◽  
Author(s):  
Søren Vinter Søgaard ◽  
Niels Erik Olesen ◽  
Cosima Hirschberg ◽  
Morten Hannibal Madsen ◽  
Morten Allesø ◽  
...  
Keyword(s):  
Experimental Evaluation ◽  
Design Methodology ◽  
Process Equipment ◽  
Powder Flow ◽  
Small Scale

Optimization of Parabolic Heliostat Focal Lengths in a Mini-Tower Solar Concentrator System

2011 ◽  
Author(s):  
Karim Hamza ◽  
Umesh Gandhi ◽  
Kazuhiro Saitou
Keyword(s):  
High Temperature ◽  
Concentration Ratio ◽  
Focal Length ◽  
Low Cost ◽  
Small Scale ◽  
Angle Of Incidence ◽  
Solar Concentrator ◽  
Effective Focal Length ◽  
Unit Energy ◽  
Utility Scale

Solar tower with heliostat mirrors is one of the established setups for utility-scale solar energy harvesting. Advantages of the setup include the capability to reach high temperature, modularity and ease of maintenance for the heliostats, containment of the high temperature zone atop the tower, as well as overall low cost per unit energy. However, downscaling to medium or small scale applications often does not turn out economically feasible with flat mirror heliostats that are the norm in utility-scale systems. This is mainly due to the need to preserve the solar concentration ratio, which in turn means the number of flat mirrors cannot be reduced. Use of parabolic mirrors instead can significantly reduce the required number of mirrors for smaller scale systems, but comes with new challenges. Unlike flat mirrors that have infinite effective focal length, the effective focal length of parabolic mirrors changes with the angle of incidence, which in turn, changes throughout the day and season. The design challenge tackled in this paper is that of optimal selection of the focal lengths of the heliostats in order to maximize the yearly harvested energy while maintaining the concentration ratio within desirable limits. A parameterized system model is developed and a genetic algorithm is implemented for the optimization task. The model is then applied to a demonstration case study of a 10 kW solar concentrator. Results of the study demonstrate the proposed design approach as well as show the promise for effective downscaling of tower and heliostat systems.

Development and experimental evaluation of an innovative self-boosting energy recovery device for small-scale SWRO system

2020 ◽  
Vol 181 ◽  
pp. 28-37
Author(s):  
Junjie Tian ◽  
Yue Wang ◽  
Jie Zhou ◽  
Zhisong He ◽  
Shichang Xu
Keyword(s):  
Experimental Evaluation ◽  
Energy Recovery ◽  
Small Scale

scholarly journals Experimental Evaluation of Advertisement-Based Bluetooth Low Energy Communication

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 107 ◽  
Author(s):  
Maciej Nikodem ◽  
Marek Bawiec
Keyword(s):  
Experimental Evaluation ◽  
Large Scale ◽  
Low Energy ◽  
Small Scale ◽  
Angle Of Arrival ◽  
Communication Performance ◽  
Bluetooth Low Energy ◽  
Iot Applications ◽  
Wide Range ◽  
The Impact

This paper addresses the efficiency of Bluetooth Low Energy (BLE) communication in a network composed of a large number of tags that transmit information to a single hub using advertisement mode. Theoretical results show that the use of advertisements enables hundreds and thousands of BLE devices to coexist in the same area and at the same time effectively transmit messages. Together with other properties (low power consumption, medium communication range, capability to detect a signal’s angle-of-arrival, etc.), this makes BLE a competing technology for the Internet of Things (IoT) applications. However, as the number of communicating devices increases, the advertisement collision intensifies and the communication performance of BLE drops. This phenomena was so far analyzed theoretically, in simulations and in small-scale experiments, but large-scale experiments are not presented in the literature. This paper complements previous results and presents an experimental evaluation of a real IoT-use case, which is the deployment of over 200 tags communicating using advertisements. We evaluate the impact of the number of advertisements on the effective data reception rate and throughput. Despite the advertisement collision rate in our experiment varying between 0.22 and 0.33, we show that BLE, thanks to the multiple transmission of advertisements, can still ensure acceptable data reception rates and fulfill the requirements of a wide range of IoT applications.

Low-Cost Solar Mirror Substrates and Geometries for Solar Thermal and Photovoltaic Concentrator Applications

2001 ◽  
Author(s):  
David N. Wells
Keyword(s):  
Motion Tracking ◽  
Low Cost ◽  
Float Glass ◽  
Solar Thermal ◽  
Small Scale ◽  
Solar Concentrator ◽  
Hail Damage ◽  
Low Profile ◽  
Cylindrical Reflector ◽  
Cylindrical Mirror

Abstract Two principal approaches to lowering solar concentrator costs are through improved geometry (lower profile, simpler shape), and through simplified methods to make concentrator substrates. The paper discusses issues relating to fabrication of solar concentrator mirrors from inexpensive elastically bent float glass mirrors. Protection from hail damage by a novel shock absorbing back layer is presented. New low-profile concentrator geometry is presented which utilize the low-cost mirror substrates. One new geometry uses a stationary cylindrical reflector with novel arc-motion tracking absorber that appears suitable for mid-sized thermal applications. Another uses the cylindrical mirror with an azimuth-elevation tracking mechanism appears to be suitable for small-scale applications. To get even higher concentration, some low-cost secondary designs are briefly discussed which use refractive tubes or lenses as secondary concentrating elements.

Sign in / Sign up

Export Citation Format

Share Document