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Connecting Micro-Generators in Parallel to the Low Voltage Distribution Network Utilising Standard EN50438 in the Republic of Ireland

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Technological University Dublin ARROW@TU Dublin Other resources School of Electrical and Electronic Engineering 2010 Connecting Micro-Generators in Parallel to the Low Voltage Distribution Network Utilising Standard EN50438 in the Republic of Ireland Liam Murphy Technological University Dublin, [email protected] Follow this and additional works at: https://arrow.tudublin.ie/engschelecon Part of the Electrical and Computer Engineering Commons Recommended Citation Murphy, L., : Connecting Micro-Generators in Parallel to the Low Voltage Distribution Network Utilising Standard EN50438 in the Republic of Ireland, University of Ulster, Dissertation. Master of Science (MSc), University of Ulster, 2010. This Dissertation is brought to you for free and open access by the School of Electrical and Electronic Engineering at ARROW@TU Dublin. It has been accepted for inclusion in Other resources by an authorized administrator of ARROW@TU Dublin. For more information, please contact [email protected], [email protected]. This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 License UNIVERSITY OF ULSTER Liam Murphy Connecting micro-generators in parallel to the low voltage distribution network utilising standard EN50438 in the Republic of Ireland SCHOOL OF THE BUILT ENVIRONMENT May 2010 MSc Thesis UNIVERSITY OF ULSTER SCHOOL OF THE BUILT ENVIRONMENT Academic Year 2009-2010 Liam Murphy Connecting micro-generators in parallel to the low voltage distribution network utilising standard EN50438 in the Republic of Ireland Supervisor: Dr. Ye Huang May 2010 This thesis is submitted as part of the requirements for the degree of Master of Science (MSc) Abstract The green agenda has been much to the fore internationally and has particularly had an influence in Republic of Ireland (ROI) where there are ‘green’ ministers in Government. Mr. Eamon Ryan who is the Minister for Communications, Energy and Natural Resources has particularly championed the idea of self generation. The author’s interest in the subject matter is to investigate the up-take of micro-generation and determine the likely short term future along with the grid tie standard i.e. EN50438. Issues surrounding micro-generation are considered from the international and national perspective and from a customer and generation utility point of view. The market for micro-generation in the ROI is examined and particularly the tariffs offered for export. Two case studies are investigated; a micro-Combined Heat and Power (CHP) unit operational since early 2008 and a micro-wind unit which has become operational since February 2010. Type certification issues with Chinese manufactured wind turbines are discussed backed up with case studies from Northern Ireland (NI). The principal methods of investigation were by researching, particularly by discussion (qualitative means) with key stakeholders in the ROI and United Kingdom (UK) and by research of the relevant literature. In addition, an analysis of the performance of a photovoltaic (PV) inverter located at DIT was carried out (quantitative analysis). Micro-generation has important role to play from a national and international perspective in reducing dependence on central generation and in Green House Gases (GHG) reduction strategies. EN50438 has a role in ensuring the safe connection of grid tied micro-generation and has been adopted by Electricity Supply Board Networks (ESBN). i Acknowledgements The author acknowledges the invaluable support received from colleagues in the Dublin Institute of Technology (DIT) throughout the period of the research but particularly in facilitating data harvesting from one of the photovoltaic (PV) arrays located on the Kevin Street campus. The author particularly wishes to thank the following colleagues, Mr. Derek Kearney, Mr. Keith Sunderland, Mr. Thomas Woolmington and Mr. Eamonn Murphy. The author also wishes to extend a heartfelt thanks to all my family who sacrificed so much quality family time in order to facilitate this research, particularly my wife Carol, my mother Bridie and my children Clodagh, Dearbhla and Aoife. The author also wishes to extend thanks to the University of Ulster for acceptance onto the MSc programme and particular thanks to the course coordinator Dr. Philip Griffiths and my mentor, Dr. Ye Huang, for his guidance during the research. Acknowledgement is also extended to the industry contacts that facilitated the case studies, Mr. Micheal Galvin, micro-Combined Heat and Power (micro-CHP) and Mr. Peter Stone (micro-wind). ii Table of Contents Abstract .............................................................................................................................. i Acknowledgements ........................................................................................................... ii List of Tables..................................................................................................................... v List of Figures .................................................................................................................. vi Abbreviations ................................................................................................................. viii Nomenclature .................................................................................................................... x Note on Access to Contents ............................................................................................. xi 1.0 Introduction ............................................................................................................ 1 1.1 What is Micro-generation ................................................................................... 2 2.0 Literature Review ................................................................................................... 6 2.1 Irish Literature .................................................................................................... 6 2.2 International Literature ..................................................................................... 12 2.2.1 Portugal ..................................................................................................... 12 2.2.2 United Kingdom ........................................................................................ 15 2.3 Conclusions ...................................................................................................... 20 3.0 Research Methodology......................................................................................... 22 3.1 Introduction and Scope ..................................................................................... 22 3.2 Aims and Objectives ........................................................................................ 24 4.0 Evolution of EN50438 ......................................................................................... 26 4.1 Requirements of EN50438 ............................................................................... 26 4.2 Discussion of EN50438 Requirements ............................................................. 35 4.3 Discussion and Evaluation of EN50438 Adoption ........................................... 38 4.4 Type Certification Issues .................................................................................. 41 5.0 Discussion and Analysis of the 40% Transformer Capacity Limit ...................... 46 6.0 Efficiency of PV Inverter (DIT) ........................................................................... 54 7.0 Case Study – Micro-CHP Connected Generator .................................................. 74 7.1 Baxi Micro-CHP ............................................................................................... 80 8.0 Case Study – Micro-Wind Generator ................................................................... 83 9.0 Conclusions and Recommendations for Further Work ........................................ 91 9.1 ROI Grid Development .................................................................................... 95 9.2 Tariffs and DSO Economic Considerations ..................................................... 99 iii 9.3 Specifier and Installer Training ...................................................................... 101 10.0 References .......................................................................................................... 103 11.0 Appendices ......................................................................................................... 113 A. An Overview of Relevant Regulations for DG ..................................................... 113 B. PV System Data .................................................................................................... 114 B.1 Sunny Boy Control Plus Datasheet ................................................................ 114 B.2 SB 1100LV Datasheet ................................................................................... 115 B.3 SMA Quotation and Technical Data .............................................................. 119 B.4 Solarwatt PV Panel Datasheet ........................................................................ 124 C. Dachs Micro-CHP G83/1 Test Certificate ............................................................ 126 D. Micro-Wind System .............................................................................................. 130 D.1 Micro-Wind Inverter G83/1 Certification ...................................................... 130 D.2
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