Performance Analysis of a Combined Solar-Assisted Heat Pump Heating System in Xi’An, China
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Economic and Environmental Analysis of Investing in Solar Water Heating Systems
sustainability Article Economic and Environmental Analysis of Investing in Solar Water Heating Systems Alexandru ¸Serban 1, Nicoleta B˘arbu¸t˘a-Mi¸su 2, Nicoleta Ciucescu 3, Simona Paraschiv 4 and Spiru Paraschiv 4,* 1 Faculty of Civil Engineering, Transilvania University of Brasov, 500152 Brasov, Romania; [email protected] 2 Faculty of Economics and Business Administration, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania; [email protected] 3 Faculty of Economics, Vasile Alecsandri University of Bacau, 157 Marasesti Street, 600115 Bacau, Romania; [email protected] 4 Faculty of Engineering, Dunarea de Jos University of Galati, 47 Domneasca Street, 800008 Galati, Romania; [email protected] * Correspondence: [email protected]; Tel.: +40-721-320-403 Academic Editor: Francesco Asdrubali Received: 26 August 2016; Accepted: 2 December 2016; Published: 8 December 2016 Abstract: Solar water heating (SWH) systems can provide a significant part of the heat energy that is required in the residential sector. The use of SWH systems is motivated by the desire to reduce energy consumption and especially to reduce a major source of greenhouse gas (GHG) emissions. The purposes of the present paper consist in: assessing the solar potential; analysing the possibility of using solar energy to heat water for residential applications in Romania; investigating the economic potential of SWH systems; and their contribution to saving energy and reducing CO2 emissions. The results showed that if solar systems are used, the annual energy savings amount to approximately 71%, and the reduction of GHG emissions into the atmosphere are of 18.5 tonnes of CO2 over the lifespan of the system, with a discounted payback period of 6.8–8.6 years, in accordance with the savings achieved depending on system characteristics, the solar radiation available, ambient air temperature and on heating load characteristics. -
Modeling PCM Phase Change Temperature and Hysteresis in Ventilation Cooling and Heating Applications
energies Article Modeling PCM Phase Change Temperature and Hysteresis in Ventilation Cooling and Heating Applications Yue Hu *, Rui Guo , Per Kvols Heiselberg and Hicham Johra Division of Architectural Engineering, Department of the Built Environment, Aalborg University, Thomas Manns Vej 23, DK-9220 Aalborg Øst, Denmark; [email protected] (R.G.); [email protected] (P.K.H.); [email protected] (H.J.) * Correspondence: [email protected] Received: 22 October 2020; Accepted: 1 December 2020; Published: 6 December 2020 Abstract: Applying phase change material (PCM) for latent heat storage in sustainable building systems has gained increasing attention. However, the nonlinear thermal properties of the material and the hysteresis between the two-phase change processes make the modelling of PCM challenging. Moreover, the influences of the PCM phase transition and hysteresis on the building thermal and energy performance have not been fully understood. This paper reviews the most commonly used modelling methods for PCM from the literature and discusses their advantages and disadvantages. A case study is carried out to examine the accuracy of those models in building simulation tools, including four methods to model the melting and freezing process of a PCM heat exchanger. These results are compared to experimental data of the heat transfer process in a PCM heat exchanger. That showed that the four modelling methods are all accurate for representing the thermal behavior of the PCM heat exchanger. The model with the DSC Cp method with hysteresis performs the best at predicting the heat transfer process in PCM in this case. The impacts of PCM phase change temperature and hysteresis on the building energy-saving potential and thermal comfort are analyzed in another case study, based on one modelling method from the first case study. -
A Comprehensive Review of Thermal Energy Storage
sustainability Review A Comprehensive Review of Thermal Energy Storage Ioan Sarbu * ID and Calin Sebarchievici Department of Building Services Engineering, Polytechnic University of Timisoara, Piata Victoriei, No. 2A, 300006 Timisoara, Romania; [email protected] * Correspondence: [email protected]; Tel.: +40-256-403-991; Fax: +40-256-403-987 Received: 7 December 2017; Accepted: 10 January 2018; Published: 14 January 2018 Abstract: Thermal energy storage (TES) is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes. This paper is focused on TES technologies that provide a way of valorizing solar heat and reducing the energy demand of buildings. The principles of several energy storage methods and calculation of storage capacities are described. Sensible heat storage technologies, including water tank, underground, and packed-bed storage methods, are briefly reviewed. Additionally, latent-heat storage systems associated with phase-change materials for use in solar heating/cooling of buildings, solar water heating, heat-pump systems, and concentrating solar power plants as well as thermo-chemical storage are discussed. Finally, cool thermal energy storage is also briefly reviewed and outstanding information on the performance and costs of TES systems are included. Keywords: storage system; phase-change materials; chemical storage; cold storage; performance 1. Introduction Recent projections predict that the primary energy consumption will rise by 48% in 2040 [1]. On the other hand, the depletion of fossil resources in addition to their negative impact on the environment has accelerated the shift toward sustainable energy sources. -
Solar Community Energy and Storage Systems for Cold Climates
SOLAR COMMUNITY ENERGY AND STORAGE SYSTEMS FOR COLD CLIMATES by Farzin Masoumi Rad Bachelor of Applied Science (Mechanical Engineering), Shiraz University, Iran, 1986 Master of Applied Science (Mechanical Engineering), Ryerson University, Toronto, Canada, 2009 A dissertation presented to Ryerson University in partial fulfilment of the requirements for degree of Doctor of Philosophy in the program of Mechanical and Industrial Engineering Toronto, Ontario, Canada, 2016 © Farzin M. Rad 2016 Author’s Declaration I hereby declare that I am the sole author of this dissertation. This is a true copy of the dissertation, including any required final revisions, as accepted by my examiners. I authorize Ryerson University to lend this thesis to other institutions or individuals for the purpose of scholarly research. I further authorize Ryerson University to reproduce this thesis by photocopying or by other means, at the request of other institutions or individuals for the purpose of scholarly research. I understand that my dissertation may be made electronically available to the public. ii SOLAR COMMUNITY ENERGY AND STORAGE SYSTEMS FOR COLD CLIMATES Farzin Masoumi Rad Doctor of Philosophy Department of Mechanical and Industrial Engineering Ryerson University, Toronto, Ontario, Canada, 2016 Abstract For a hypothetical solar community located in Toronto, Ontario, the viability of two separate combined heating and cooling systems were investigated. Four TRNSYS integrated models were developed for different cases. First, an existing heating only solar community was modeled and compared with published performance data as the base case with suggested improvements. The base case community was then used to develop a hypothetical solar community, located in Toronto, requiring both heating and cooling. -
Performance Prediction of a Solar District Cooling System in Riyadh, Saudi T Arabia – a Case Study ⁎ G
Energy Conversion and Management 166 (2018) 372–384 Contents lists available at ScienceDirect Energy Conversion and Management journal homepage: www.elsevier.com/locate/enconman Performance prediction of a solar district cooling system in Riyadh, Saudi T Arabia – A case study ⁎ G. Franchini , G. Brumana, A. Perdichizzi Department of Engineering and Applied Sciences, University of Bergamo, 5 Marconi Street, Dalmine 24044, Italy ARTICLE INFO ABSTRACT Keywords: The present paper aims to evaluate the performance of a solar district cooling system in typical Middle East Solar cooling climate conditions. A centralized cooling station is supposed to distribute chilled water for a residential com- District cooling pound through a piping network. Two different solar cooling technologies are compared: two-stage lithium- Parabolic trough bromide absorption chiller (2sABS) driven by Parabolic Trough Collectors (PTCs) vs. single-stage lithium-bro- Absorption chiller mide absorption chiller (1sABS) fed by Evacuated Tube Collectors (ETCs). A computer code has been developed Thermal storage in Trnsys® (the transient simulation software developed by the University of Wisconsin) to simulate on hourly basis the annual operation of the solar cooling system, including building thermal load calculation, thermal losses in pipes and control strategy of the energy storage. A solar fraction of 70% was considered to size the solar field aperture area and the chiller capacity, within a multi-variable optimization process. An auxiliary com- pression chiller is supposed to cover the peak loads and to be used as backup unit. The two different solar cooling plants exhibit strongly different performance. For each plant configuration, the model determined the optimal size of every component leading to the primary cost minimization. -
A Review on Roughness Geometry Used in Solar Air Heaters
Available online at www.sciencedirect.com Solar Energy 81 (2007) 1340–1350 www.elsevier.com/locate/solener A review on roughness geometry used in solar air heaters Varun a, R.P. Saini b, S.K. Singal b,* a Department of Mechanical Engineering, Moradabad Institute of Technology, Ram Ganga Vihar, Moradabad 244001, India b Alternate Hydro Energy Centre, Indian Institute of Technology, Roorkee 247667, India Received 16 June 2006; received in revised form 29 January 2007; accepted 31 January 2007 Available online 28 February 2007 Communicated by: Associate Editor Brian Norton Abstract The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of a solar air heater. Number of geometries of roughness elements has been investigated on the heat transfer and friction characteristics of solar air heater ducts. In this paper an attempt has been made to review on element geometries used as artificial roughness in solar air heaters in order to improve the heat transfer capability of solar air heater ducts. The correlations developed for heat transfer and friction factor in roughened ducts of solar air heaters by various investigators have been reviewed and presented. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Solar air heater; Artificial roughness; Effective efficiency; Heat transfer; Friction factor 1. Introduction these can also be effectively used for curing/drying of concrete/clay building components. The solar air heater Energy in various forms has played an increasingly occupies an important place among solar heating system important role in world wide economic progress and indus- because of minimal use of materials and cost. -
Solar Combisystems
Method and comparison of advanced storage concepts A Report of IEA Solar Heating and Cooling programme - Task 32 “Advanced storage concepts for solar and low energy buildings” Report A4 of Subtask A December 2007 Jean-Christophe Hadorn Thomas Letz Michel Haller Method and comparison of advanced storage concepts Jean-Christophe Hadorn, BASE Consultants SA, Geneva, Switzerland Thomas Letz INES Education, Le Bourget du Lac, France Contribution on method: Michel Haller Institute of Thermal Engineering Div. Solar Energy and Thermal Building Simulation Graz University of Technology Inffeldgasse 25 B, A-8010 Graz A technical report of Subtask A BASE CONSULTANTS SA 8 rue du Nant CP 6268 CH - 1211 Genève INES - Education Parc Technologique de Savoie Technolac 50 avenue du Léman BP 258 F - 73 375 LE BOURGET DU LAC Cedex 3 Executive Summary This report presents the criteria that Task 32 has used to evaluate and compare several storage concepts part of a solar combisystem and a comparison of storage solutions in a system. Criteria have been selected based on relevance and simplicity. When values can not be assessed for storage techniques to new to be fully developped, we used more qualitative data. Comparing systems is always a very hard task. Boundary conditions and all paramaters must be comparable. This is very difficult to achieve when 9 analysts work around the world on similar systems but with different storage units. This report is an attempt of a comparison. Main generic results that we can draw with some confidency from the inter comparison of systems are: - The drain back principle increases thermal performances because it does not use of a heat exchanger in the solar loop and increases therefore the efficiency of the solar collector. -
RESET CHAPTER 2: Development and Assessment of Methodologies to Improve Local Microclimate with the Use of RES Techniques
CONTENTS RESSET - Chapter 1: Collection and documentation of the input data and evaluation tools required to carry out the study................................................................................................................................ 4 1. Development and assessment of methodologies to improve local microclimate with the use of RES techniques............................................................................................................................................. 4 1.1. Introduction.................................................................................................................................... 4 1.2. Energy Balance of Settlements ...................................................................................................... 4 1.3. Microclimate in Settlements .......................................................................................................... 5 1.4. Use of Passive Cooling Techniques applied to Outdoor Spaces ................................................... 6 2. Passive solar heating and cooling and advanced glazing materials...................................................... 8 2.1. Introduction.................................................................................................................................... 8 2.2. Building-integrated PV .................................................................................................................. 8 2.3. Passive solar systems .................................................................................................................... -
Utilizing Solar Energy to Reduce Air Pollution in Ulaanbaatar
Die approbierte Originalversion dieser Diplom-/ Masterarbeit ist in der Hauptbibliothek der Tech- nischen Universität Wien aufgestellt und zugänglich. MSc Program http://www.ub.tuwien.ac.at Environmental Technology & International Affairs The approved original version of this diploma or master thesis is available at the main library of the Vienna University of Technology. http://www.ub.tuwien.ac.at/eng Utilizing Solar Energy to Reduce Air Pollution in Ulaanbaatar A Master’s Thesis submitted for the degree of “Master of Science” supervised by Prof. Dr. Günther Brauner Enkhchimeg Munkhgerel 1528141 Vienna, 25.05.2017 Affidavit I, ENKHCHIMEG MUNKHGEREL, hereby declare 1. that I am the sole author of the present Master’s Thesis, "UTILIZING SOLAR ENERGY TO REDUCE AIR POLLUTION IN ULAANBAATAR", 63 pages, bound, and that I have not used any source or tool other than those referenced or any other illicit aid or tool, and 2. that I have not prior to this date submitted this Master’s Thesis as an examination paper in any form in Austria or abroad. Vienna, 25.05.2017 Signature Abstract Ulaanbaatar, the capital city of Mongolia, is among the top 5 cities with worst air quality in the world. Particulate matter pollution is extreme during winter with PM2.5 3 3 and PM10 reaching 436 µg/m and 1100 µg/m , respectively. One of the major air pollution sources is suburban traditional housing areas called “ger districts”. Households of ger districts consume approximately 850,000 tons of coal per year primarily for heating purposes, emitting tons of pollutants into the atmosphere. This thesis presents possibilities of utilizing solar energy to reduce air pollution from ger districts. -
Integration of Micro-Cogeneration Units and Electric Storages Into a Micro-Scale Residential Solar District Heating System Operating with a Seasonal Thermal Storage
energies Article Integration of Micro-Cogeneration Units and Electric Storages into a Micro-Scale Residential Solar District Heating System Operating with a Seasonal Thermal Storage Antonio Rosato * , Antonio Ciervo, Giovanni Ciampi , Michelangelo Scorpio and Sergio Sibilio Department of Architecture and Industrial Design, University of Campania Luigi Vanvitelli, 81031 Aversa, Italy; [email protected] (A.C.); [email protected] (G.C.); [email protected] (M.S.); [email protected] (S.S.) * Correspondence: [email protected]; Tel.: +39-081-501-0845 Received: 31 July 2020; Accepted: 9 October 2020; Published: 19 October 2020 Abstract: A micro-scale district heating network based on the operation of solar thermal collectors coupled to a long-term borehole thermal storage is modeled, simulated and investigated over a period of five years. The plant is devoted to covering the domestic hot water and space heating demands of a district composed of six typical residential buildings located in Naples (southern Italy). Three alternative natural gas-fueled back-up auxiliary systems (condensing boiler and two different technologies of micro-cogeneration) aiming at balancing the solar energy intermittency are investigated. The utilization of electric storages in combination with the cogeneration systems is also considered with the aim of improving the self-consumption of cogenerated electric energy; heat recovery from the distribution circuit is also evaluated to pre-heat the mains water for domestic hot water production. The performances of the proposed plant schemes are contrasted with those of a typical Italian decentralized heating plant (based on the utilization of natural gas-fueled non-condensing boilers). -
Thermal Storage Technology Assessment an Introductory Assessment of Thermal Storage in Residential Cold Climate Construction
Thermal Storage Technology Assessment An introductory assessment of thermal storage in residential cold climate construction February 2013 by Vanessa Stevens Colin Craven Bruno Grunau With funding from the Alaska Housing Finance Cor- poration & the Alaska Department of Commerce, Community, and Economic Development Acknowledgements The authors would like to acknowledge the many people who participated in interviews for this report, sharing their knowledge and expertise on the topic of thermal storage. Several of the systems built by these individuals appear in Appendix B. Also, thanks to the Alaska Department of Commerce, Community, and Economic Development and the Alaska Housing Finance Corporation for providing funding for this project. 3 Thermal Storage Technolog y Assessment www.cchrc.org Contents Acronyms ............................................................................................................................................................ 5 Introduction ........................................................................................................................................................ 6 1. Thermal Storage Fundamentals........................................................................................................................ 7 1.1 Definition ................................................................................................................................................... 7 1.2 Uses of thermal storage ............................................................................................................................ -
Dynamic Performance of a Solar Hybrid Heating Network Integrated with a Micro
________________________________________________________________________________________________ Dynamic Performance of a Solar Hybrid Heating Network Integrated with a Micro- Cogeneration Unit Serving a Small-Scale Residential District including Electric Vehicles Antonio Rosato, Antonio Ciervo, Giovanni Ciampi, Michelangelo Scorpio, Francesco Guarino, Sergio Sibilio University of Campania Luigi Vanvitelli, Department of Architecture and Industrial Design, Aversa, Italy Abstract (Angrisani et al., 2014). The micro-cogeneration devices applied in residential units generally operate under a heat- A solar hybrid district heating network integrated with a load following control strategy in response to variations seasonal borehole thermal energy storage is modelled, in heat demand (Sibilio and Rosato, 2015); in this case, a simulated and analyzed over a 5-year period. The system large fraction of the cogenerated electricity is usually is devoted to satisfying the thermal demand of a small- produced at times when the electric demand of the scale district consisting of 6 typical Italian single-family building is lower than MCHP electric output due to the houses in Naples (south of Italy); the charging of 6 plug- usual mismatch between electric and thermal demands in electric vehicles is also considered. The performance of (Ribberink and Entchev, 2014), requiring substantial the proposed plant is investigated by considering two amounts of electricity to be exported to the grid with low alternative natural gas-fueled back-up systems. The revenues. EVs consume considerable amounts of energy, environmental and economic performance of the electricity; they are mostly driven during the day and proposed plant are analyzed and compared with those charged at home during the night, so that the recharging associated to a conventional heating system in order to of EVs could be a way to increase the own use of assess the potential benefits.