Special Issue "Solar Thermal Systems"

A special issue of Applied System Innovation (ISSN 2571-5577).

Deadline for manuscript submissions: closed (30 June 2019).

Special Issue Editor

Guest Editor
Prof. Sergio Nardini

Dipartimento di Ingegneria, Università degli Studi della Campania “Luigi Vanvitelli”, Via Roma 29, 81031 Aversa (CE), Italy
Website | E-Mail
Phone: +39 0815010347
Fax: +39 0815010204
Interests: thermal systems; active solar systems; passive solar systems; heat transfer with nanofluids and porous media; forecast of energy consumption

Special Issue Information

Dear Colleagues,

Research on solar thermal energy conversion has received, and is still receiving, attention for its importance to reduce fossil fuel use and carbon emissions. With COP 21, nations across the world agreed to accelerate their reductions in carbon emissions. Thermal energy comprises nearly half of the final global energy consumption, of which one third belongs to industry. The remarkable progress that has been made in cost reduction and commercial deployment of solar thermal energy technologies underlines the benefits of investment in R&D and indicates the promise of, and necessity for, continued innovation to produce further advances in the field. Hence, there is the need of researches on higher efficiencies, lower costs, improved scalability, and new functionality of energy thermal components and systems. Nowadays the main aims of the researches are both the seeking of new configurations and on the use of micro and nano technologies in energy thermal components and systems.

The aim of this Special Issue is to collect original research articles, as well as review articles, on the most recent developments and research efforts in this field, with the purpose of providing guidelines for future research directions. Potential topics of include, but are not limited to:

  • Solar collectors analysis and design;
  • Thermal energy storage;
  • Active solar heating and cooling systems;
  • Solar heat for residential and industrial uses;
  • Passive solar heating and cooling.
Prof. Dr. Sergio Nardini

Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied System Innovation is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Solar collectors
  • Thermal energy storage
  • Active solar heating and cooling systems
  • Solar heat for residential and industrial uses
  • Passive solar heating and cooling.

Published Papers (7 papers)

View options order results:
result details:
Displaying articles 1-7
Export citation of selected articles as:

Research

Open AccessArticle
Analysis of Nanofluids Behavior in Concentrated Solar Power Collectors with Organic Rankine Cycle
Appl. Syst. Innov. 2019, 2(3), 22; https://doi.org/10.3390/asi2030022
Received: 14 June 2019 / Revised: 2 July 2019 / Accepted: 8 July 2019 / Published: 16 July 2019
PDF Full-text (15486 KB) | HTML Full-text | XML Full-text
Abstract
In this paper, the performance of nanofluids in a Parabolic Trough Concentrating Solar Collector (CSP)-based power generation plant, an Organic Rankine Cycle (ORC), and a Thermal Energy Storage (TES) system is studied. This study is intended to investigate the enhancement effect and characteristics [...] Read more.
In this paper, the performance of nanofluids in a Parabolic Trough Concentrating Solar Collector (CSP)-based power generation plant, an Organic Rankine Cycle (ORC), and a Thermal Energy Storage (TES) system is studied. This study is intended to investigate the enhancement effect and characteristics of nanofluids Al2O3, CuO, Fe3O4 and SiO2 in integrated concentrating solar power (CSP) with ORC, and TES under different solar radiations, angles of incidence, and different nanofluid concentrations. The refrigerant mixture used in the ORC loop to enhance the ORC efficiency is an environmentally sound quaternary mixture composed of R134a, R245fa, R125, R236fa. The results showed that the power absorbed, and power collected by the CSP collector and thermal energy stored in the storage tank are enhanced with the increase of the solar radiation. It was also found that the CSP hybrid system efficiency has been enhanced mainly by the increase of the solar radiation and higher nanofluid concentrations over the thermal oil as base fluid. Also, the study concludes that the nanofluid CuO outperforms the other nanofluids—Al2O3, Fe3O4 and SiO2—and has the highest CSP solar collector performance compared to the other nanofluids and thermal oil base fluid under study at similar conditions. Finally, it was found that the model’s prediction compares fairly with data reported in the literature; however, some discrepancies exist between the model’s prediction and the experimental data. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Open AccessArticle
Estimation of Direct Normal Irradiance at Antarctica for Concentrated Solar Technology
Appl. Syst. Innov. 2019, 2(3), 21; https://doi.org/10.3390/asi2030021
Received: 27 June 2019 / Revised: 10 July 2019 / Accepted: 10 July 2019 / Published: 11 July 2019
PDF Full-text (5908 KB) | HTML Full-text | XML Full-text
Abstract
The estimation of the average daily, monthly and annual direct normal solar irradiation (DNI) was done in the region hosting the Mario Zucchelli Station, in the bay of Terra Nova (Antarctica). Estimates are based on measurements of direct normal (DNI), horizontal global (GHI) [...] Read more.
The estimation of the average daily, monthly and annual direct normal solar irradiation (DNI) was done in the region hosting the Mario Zucchelli Station, in the bay of Terra Nova (Antarctica). Estimates are based on measurements of direct normal (DNI), horizontal global (GHI) and horizontal diffuse (Diff.HI) irradiations, observed by a solar-metric acquisition station installed during the XXVIII scientific expedition carried out in the austral summer 2012/2013 as part of the National Plan of Research in Antarctica (PNRA). The contemporary observations of all three irradiations allowed the setting up of the model for the estimation of the DNI starting from the values of the GHI only, validated for the weather conditions of the Antarctic region. Subsequently, the long-time data reconstruction of the DNI values thanks to the availability of several years' hourly measurements of GHI at the Mario Zucchelli base has been carried out using the meteorological acquisition data installed both at the base and in places scattered around it. The final results make feasible the estimation of solar potential for concentrated solar technology according to long measurements of GHI. Overall, we propose a clean technology based on a renewable power plant and a specific example with a tendency toward a decreased human carbon footprint in the atmosphere of this protected area. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Open AccessFeature PaperArticle
Analysis and Adaptation of Q-Learning Algorithm to Expert Controls of a Solar Domestic Hot Water System
Appl. Syst. Innov. 2019, 2(2), 15; https://doi.org/10.3390/asi2020015
Received: 8 January 2019 / Revised: 11 April 2019 / Accepted: 19 April 2019 / Published: 25 April 2019
PDF Full-text (9884 KB) | HTML Full-text | XML Full-text
Abstract
This paper discusses the development of a coupled Q-learning/fuzzy control algorithm to be applied to the control of solar domestic hot water systems. The controller brings the benefit of showing performance in line with the best reference controllers without the need for devoting [...] Read more.
This paper discusses the development of a coupled Q-learning/fuzzy control algorithm to be applied to the control of solar domestic hot water systems. The controller brings the benefit of showing performance in line with the best reference controllers without the need for devoting time to modelling and simulations to tune its parameters before deployment. The performance of the proposed control algorithm was analysed in detail concerning the input membership function defining the fuzzy controller. The algorithm was compared to four standard reference control cases using three performance figures: the seasonal performance factor of the solar collectors, the seasonal performance factor of the system and the number of on/off cycles of the primary circulator. The work shows that the reinforced learning controller can find the best performing fuzzy controller within a family of controllers. It also shows how to increase the speed of the learning process by loading the controller with partial pre-existing information. The new controller performed significantly better than the best reference case with regard to the collectors’ performance factor (between 15% and 115%), and at the same time, to the number of on/off cycles of the primary circulator (1.2 per day down from 30 per day). Regarding the domestic hot water performance factor, the new controller performed about 11% worse than the best reference controller but greatly improved its on/off cycle figure (425 from 11,046). The decrease in performance was due to the choice of reward function, which was not selected for that purpose and it was blind to some of the factors influencing the system performance factor. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Open AccessArticle
Numerical Simulation of an Aluminum Container including a Phase Change Material for Cooling Energy Storage
Appl. Syst. Innov. 2018, 1(3), 34; https://doi.org/10.3390/asi1030034
Received: 9 August 2018 / Revised: 19 August 2018 / Accepted: 24 August 2018 / Published: 4 September 2018
PDF Full-text (8793 KB) | HTML Full-text | XML Full-text
Abstract
Thermal energy storage systems can be determinant for an effective use of solar energy, as they allow to decouple the thermal energy production by the solar source from thermal loads, and thus allowing solar energy to be exploited also during nighttime and cloudy [...] Read more.
Thermal energy storage systems can be determinant for an effective use of solar energy, as they allow to decouple the thermal energy production by the solar source from thermal loads, and thus allowing solar energy to be exploited also during nighttime and cloudy periods. The current study deals with the modelling and simulation of a cooling thermal energy storage unit consisting of an aluminum container partially filled with a phase change material (PCM). Two unsteady models are implemented and discussed, namely a conduction-based model and a conduction-convection-based one. The equations systems relative to both the models are solved by means of the Comsol Multiphysics finite element solver, and results are presented in terms of temporal variation of temperature in different points inside the PCM, of the volume average liquid fraction, and of the cooling energy stored and released through the aluminum container external surface during the charge and discharge, respectively. Moreover, the numerical results obtained by the implementation of the above different models are compared with experimental ones obtained with a climatic chamber. The comparison between numerical and experimental results indicate that, for the considered cooling energy storage unit, free convection plays a crucial role in the heat transfer inside the liquid PCM and cannot be neglected. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Open AccessFeature PaperArticle
Solar Hybrid Micro Gas Turbine Based on Turbocharger
Appl. Syst. Innov. 2018, 1(3), 27; https://doi.org/10.3390/asi1030027
Received: 7 June 2018 / Revised: 27 July 2018 / Accepted: 27 July 2018 / Published: 1 August 2018
Cited by 1 | PDF Full-text (4372 KB) | HTML Full-text | XML Full-text
Abstract
The performance of solar hybrid Brayton cycle materialized by a micro-gas turbine based on a turbocharger is studied. The use of a turbocharger is aimed at investment cost reduction and construction simplification. Two configurations are investigated, namely hybrid and solar-only. Design aspects are [...] Read more.
The performance of solar hybrid Brayton cycle materialized by a micro-gas turbine based on a turbocharger is studied. The use of a turbocharger is aimed at investment cost reduction and construction simplification. Two configurations are investigated, namely hybrid and solar-only. Design aspects are discussed, in view of the requirement for minimizing the cost of electricity produced. A key parameter is the turbine inlet temperature and its effect on performance is investigated. The effect of heliostat field size is also investigated. Augmentation of the maximum temperature leads to better performance, as a result of higher cycle efficiency. Solar-only configuration features are compared with hybrid ones and the contribution of different cost components to the final electricity cost is discussed. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Open AccessArticle
Principles of Product Design in Developing Countries
Appl. Syst. Innov. 2018, 1(2), 11; https://doi.org/10.3390/asi1020011
Received: 13 March 2018 / Revised: 10 April 2018 / Accepted: 10 April 2018 / Published: 20 April 2018
PDF Full-text (32408 KB) | HTML Full-text | XML Full-text
Abstract
Problem—The conventional view of new product development (NPD) methodologies focuses on marketing and commercial prospects in developed countries. There is a need to identify both the barriers and the enablers to design within a rural context in developing countries (DC). Method—A [...] Read more.
Problem—The conventional view of new product development (NPD) methodologies focuses on marketing and commercial prospects in developed countries. There is a need to identify both the barriers and the enablers to design within a rural context in developing countries (DC). Method—A researcher was embedded in a rural DC design project. Issues were observed and critical success and failure factors determined. These were abstracted into a set of design principles, and a new model of the NPD process was created. Findings—Whereas commercial NPD emphasizes market intelligence and a highly directive approach to the engineering workflow, in the DC situation the objective is to fulfil community needs and this necessitates co-determination regarding the engineering. There is commonality between the two NPD processes, with ours having a greater emphasis on the socio-cultural factors. The deployment principles are categorized into technical and socio-cultural. Within these are included project management, design, material selection, visualization, communication, maintainability, safety, and health. Originality—A novel representation of the process for conducting design in developing countries is provided. Critical success factors are identified. The socio-cultural perspective is explicitly included, which is absent from the conventional engineering and business perspectives. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Open AccessFeature PaperArticle
A Realistic Approach of the Maximum Work Extraction from Solar Thermal Collectors
Appl. Syst. Innov. 2018, 1(1), 6; https://doi.org/10.3390/asi1010006
Received: 2 December 2017 / Revised: 24 January 2018 / Accepted: 25 January 2018 / Published: 30 January 2018
PDF Full-text (2120 KB) | HTML Full-text | XML Full-text
Abstract
In this study, the maximum work extraction from the incident solar energy on solar thermal collectors is investigated by coupling solar collectors with a Carnot machine. A simplified thermal model for the solar collector performance is developed in which the radiation losses play [...] Read more.
In this study, the maximum work extraction from the incident solar energy on solar thermal collectors is investigated by coupling solar collectors with a Carnot machine. A simplified thermal model for the solar collector performance is developed in which the radiation losses play a significant role. In every examined case, the optimum operating temperature that leads to maximum work extraction is calculated. The final results are presented parametrically, covering a great variety of real solar collectors. Moreover, the validation procedure of the developed model proves high accuracy. The results show that non-concentrating collectors should operate up to 400 K while concentrating collectors in higher temperature levels. More specifically, a parabolic trough collector can operate efficiently in temperature levels up to 850 K, while solar dish collectors can operate efficiently in temperature levels up to 1100 K. The results of this study can be exploited for the preliminary design and optimization of solar thermal systems. Moreover, a clear and realistic upper limit concerning the exergy production of solar irradiation with solar thermal collectors is given. Full article
(This article belongs to the Special Issue Solar Thermal Systems)
Figures

Figure 1

Appl. Syst. Innov. EISSN 2571-5577 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top