Impact of Size and Scattering Mode on the Optimal Solar Absorbing Nanofluid

The concept of using a direct absorbing nanofluid, a liquid-nanoparticle suspension, has recently been shown numerically and experimentally to be an efficient method for harvesting solar thermal energy. Studies show that the size and shape of the nanoparticles as well as the scattering mode (e.g. dependent, independent, and multiple) all impact the amount of energy absorbed and emitted by the nanofluid. In order to optimize the efficiency of a direct absorption solar thermal system the optimum nanoparticle-liquid combination needs to be developed. The optimum nanofluid for a direct absorption solar thermal collector is investigated numerically through the variation of particle size, including the impact of size on optical properties, and scattering mode. The study addresses both the absorption of solar energy within the fluid as well as the emission of the fluid.

Download Full-text

Analytical modeling and experimental investigation on optical properties of new class of nanofluids (Al2O3–CuO binary nanofluids) for direct absorption solar thermal energy

Optical Materials ◽

10.1016/j.optmat.2015.12.023 ◽

2016 ◽

Vol 52 ◽

pp. 116-125 ◽

Cited By ~ 19

Author(s):

Amir Menbari ◽

Ali Akbar Alemrajabi

Keyword(s):

Experimental Investigation ◽

Optical Properties ◽

Thermal Energy ◽

Analytical Modeling ◽

Solar Thermal ◽

Direct Absorption ◽

Solar Thermal Energy ◽

New Class

Download Full-text

Predictive control of a solar thermal system via on-line communication with a meteorological database server

Időjárás ◽

10.28974/idojaras.2021.2.3 ◽

2021 ◽

Vol 125 (2) ◽

pp. 211-227

Author(s):

János Tóth ◽

István Farkas

Keyword(s):

Predictive Control ◽

Control Method ◽

Storage System ◽

Real Life ◽

Solar Thermal ◽

Thermal System ◽

Database Server ◽

Solar Thermal Collector ◽

On Line ◽

Solar Thermal System

In this paper, the mathematical models of a solar thermal system which governs the solar thermal collector, the heat storage system, and the pump are presented. It has been shown that it is possible to connect a Simulink-based model to a meteorological database server using standard communication protocols by a C language-based component in order to import real-life weather information into the simulation. The setup of the model predictive control of this solar thermal system and the results of the simulation are also presented. This computationally heavy control method is possible to use on today's personal computers, and it can be expanded.

Download Full-text

Comparison of Performance of Desiccant Air Handling Unit with Solar Thermal System under Various Control Methods

E3S Web of Conferences ◽

10.1051/e3sconf/201911101077 ◽

2019 ◽

Vol 111 ◽

pp. 01077

Author(s):

Makiko Ukai ◽

Masaya Okumiya

Keyword(s):

Thermal Energy ◽

Absolute Humidity ◽

Solar Thermal ◽

Thermal System ◽

Control Methods ◽

Important Process ◽

Solar Thermal Energy ◽

Flexible Control ◽

Air Handling Unit ◽

Solar Thermal System

In hot and humid summer as in Japan, dehumidification is important process for air conditioning. Desiccant air handling unit is one of the major system for dehumidification in which absorbent or sorbent absorbs moisture in the air and hot heat source is required in order to regenerate them. In order to use solar thermal energy efficiently, flexible control, which controls the distribution of the dehumidification at precooling coil and dehumidification wheel, is proposed and analysed its performance through simulation. Simulation results show that supply absolute humidity fulfils the set point even when solar thermal energy is not supplied to regenerating coil under flexible control. On the other hand, system with conventional fixed control can not fulfil the set absolute humidity when solar thermal energy is not supplied. The unprocessed latent heat load is around 49kW, which results in higher relative humidity around 56.5%. Solar thermal energy supplied to regenerating coil under flexible control is larger than fixed control.

Download Full-text

Thermo-optical properties of partially unzipped multiwalled carbon nanotubes dispersed nanofluids for direct absorption solar thermal energy systems

Solar Energy Materials and Solar Cells ◽

10.1016/j.solmat.2016.05.037 ◽

2016 ◽

Vol 157 ◽

pp. 117-125 ◽

Cited By ~ 38

Author(s):

Rashmi Chandrabhan Shende ◽

S Ramaprabhu

Keyword(s):

Carbon Nanotubes ◽

Optical Properties ◽

Multiwalled Carbon Nanotubes ◽

Thermal Energy ◽

Energy Systems ◽

Solar Thermal ◽

Direct Absorption ◽

Solar Thermal Energy ◽

Multiwalled Carbon

Download Full-text

Experimental investigation of a silver nanoparticle-based direct absorption solar thermal system

Energy Conversion and Management ◽

10.1016/j.enconman.2014.04.009 ◽

2014 ◽

Vol 84 ◽

pp. 261-267 ◽

Cited By ~ 114

Author(s):

Enio Pedone Bandarra Filho ◽

Oscar Saúl Hernandez Mendoza ◽

Carolina Lau Lins Beicker ◽

Adonis Menezes ◽

Dongsheng Wen

Keyword(s):

Experimental Investigation ◽

Silver Nanoparticle ◽

Solar Thermal ◽

Thermal System ◽

Direct Absorption ◽

Solar Thermal System

Download Full-text

Performance Modeling of a Solar Thermal System for Cooling and Heating in Carnegie Mellon University’s Intelligent Workplace

ASME 2007 Energy Sustainability Conference ◽

10.1115/es2007-36053 ◽

2007 ◽

Cited By ~ 1

Author(s):

Sophie V. Masson ◽

Ming Qu ◽

David H. Archer

Keyword(s):

System Integration ◽

Building Design ◽

Energy Performance ◽

Hot Water ◽

Solar Thermal ◽

Solar Array ◽

Thermal System ◽

Solar Absorption ◽

Solar Thermal System ◽

The Impact

The Robert L. Preger Intelligent Workplace (IW) is a 650 m2 living laboratory of office space at Carnegie Mellon University (Pittsburgh, PA). The IW has received the first commercially available solar absorption system for air-conditioning with integrated controls as a donation from BROAD in August 2006. The IW is now testing this solar thermal system. A TRNSYS model has been developed and used to assist the design of the system, evaluate its performance throughout an entire year, and optimize its initial configuration. The components of the system are a 52 m2 parabolic trough high temperature solar array, a 16 kW hot water and gas fired absorption chiller, and an overall control system. This model predicts the energy required to cool and heat the south part of the IW (around 10 MWh in winter, 15 MWh in summer) and the fraction of that energy that can be provided by solar energy. The effects of significant system parameters — orientation of the receivers, volume of hot/chilled water thermal storage and insulation thicknesses on the piping and tank — on the fraction of solar provided energy have been calculated by the model. This study emphasizes on two significant aspects: - the impact of system integration during the preliminary building design on the energy performance, - the importance of the energy modeling to assist and optimize the design of the system and its operation but also to reduce the investment and operation costs.

Download Full-text

Optical properties of liquids for direct absorption solar thermal energy systems

Solar Energy ◽

10.1016/j.solener.2008.12.009 ◽

2009 ◽

Vol 83 (7) ◽

pp. 969-977 ◽

Cited By ~ 268

Author(s):

Todd P. Otanicar ◽

Patrick E. Phelan ◽

Jay S. Golden

Keyword(s):

Optical Properties ◽

Thermal Energy ◽

Energy Systems ◽

Solar Thermal ◽

Direct Absorption ◽

Solar Thermal Energy

Download Full-text

Overall Efficiency of On-Site Production and Storage of Solar Thermal Energy

Sustainability ◽

10.3390/su13031360 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1360

Author(s):

Teodora M. Șoimoșan ◽

Ligia M. Moga ◽

Livia Anastasiu ◽

Daniela L. Manea ◽

Aurica Căzilă ◽

...

Keyword(s):

Energy Efficiency ◽

Thermal Energy ◽

Urban Areas ◽

Renewable Energy Sources ◽

Multicriteria Analysis ◽

High Energy ◽

Solar Thermal ◽

Solar Thermal Energy ◽

The Impact ◽

And Storage

Harnessing renewable energy sources (RES) using hybrid systems for buildings is almost a deontological obligation for engineers and researchers in the energy field, and increasing the percentage of renewables within the energy mix represents an important target. In crowded urban areas, on-site energy production and storage from renewables can be a real challenge from a technical point of view. The main objectives of this paper are quantification of the impact of the consumer’s profile on overall energy efficiency for on-site storage and final use of solar thermal energy, as well as developing a multicriteria assessment in order to provide a methodology for selection in prioritizing investments. Buildings with various consumption profiles lead to achieving different values of performance indicators in similar configurations of storage and energy supply. In this regard, an analysis of the consumption profile’s impact on overall energy efficiency, achieved in the case of on-site generation and storage of solar thermal energy, was performed. The obtained results validate the following conclusion: On-site integration of solar systems allowed the consumers to use RES at the desired coverage rates, while restricted by on-site available mounting areas for solar fields and thermal storage, under conditions of high energy efficiencies. In order to segregate the results and support optimal selection, a multicriteria analysis was carried out, having as the main criteria the energy efficiency indicators achieved by hybrid heating systems.

Download Full-text

Design, Installation, and Performance Characterization of a Laboratory-Scale Solar Thermal System for Experiments in Solar Energy Utilization

Volume 5: Education and Globalization; General Topics ◽

10.1115/imece2012-86361 ◽

2012 ◽

Author(s):

Stephanie Drozek ◽

Christopher Damm ◽

Ryan Enot ◽

Andrew Hjortland ◽

Brandon Jackson ◽

...

Keyword(s):

Renewable Energy ◽

Solar Energy ◽

Laboratory Scale ◽

Energy Utilization ◽

Solar Thermal ◽

Thermal System ◽

Performance Characterization ◽

And Performance ◽

Solar Thermal System

The purpose of this paper is to describe the implementation of a laboratory-scale solar thermal system for the Renewable Energy Systems Laboratory at the Milwaukee School of Engineering (MSOE). The system development began as a student senior design project where students designed and fabricated a laboratory-scale solar thermal system to complement an existing commercial solar energy system on campus. The solar thermal system is designed specifically for educating engineers. This laboratory equipment, including a solar light simulator, allows for variation of operating parameters to investigate their impact on system performance. The equipment will be utilized in two courses: Applied Thermodynamics, and Renewable Energy Utilization. During the solar thermal laboratories performed in these courses, students conduct experiments based on the American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) 93-2010 standard for testing and performance characterization of solar thermal systems. Their measurements are then used to quantify energy output, efficiency and losses of the system and subsystem components.

Download Full-text