Energy efficiency is today a crucial topic in the built environment - for both designers and managers of buildings. This increased interest is driven by a combination of new regulations and directives within the EU and worldwide to combat global warming. All buildings now must now acquire and display an EPC (energy performance certificate), a rating similar to the AG rating given to white goods. But in order to understand how to be more efficient in energy use, you need first to understand the mechanisms of both energy requirements and howenergy is used in buildings. Energy Audits: a workbook for energy managementin buildings tackles the fundamental principles of thermodynamics through day-to-day engineering concepts and helps students understand why energy losses occur and how they can be reduced. It provides the tools to measure process efficiency and sustainability in power and heating applications, helping engineers to recognize why energy losses occur and how they can be reduced utilizing familiar thermodynamic principles. The author describes the sources of energy available today; explains how energy is used in buildings and how energy is lost - and how this can be controlled and reduced. Investments in energy efficiency are considered for a number of case studies conducted on real buildings Thebook explains the theory; illustrates it with case studies and worked examples; and then tests students understanding with tutorial problems. This is an invaluable resource for students on engineering and building courses where energy management is now a core topic. INDICE: Preface xi Acknowledgements xiii Dimensions and Units xv List of Figures xxi List of Tables xxv 1 Energy and the Environment 1 1.1 Introduction 2 1.2 Forms of energy 2 1.2.1 Mechanical energy 2 1.2.2 Electrical energy 3 1.2.3 Chemical energy 4 1.2.4 Nuclear energy 4 1.2.5 Thermal energy 5 1.3 Energyconversion 6 1.4 The burning question 8 1.4.1 Combustion of coal 9 1.4.2 Combustion of oil 10 1.4.3 Combustion of natural gas 10 1.5 Environmental impact from fossil fuels 11 1.6 Energy worldwide 12 1.7 Energy and the future 13 1.7.1The dream scenario 15 1.7.2 The renewable scenario 15 1.8 Worked examples 15 1.9 Tutorial problems 19 1.10 Case Study: Future energy for the world 20 2 Energy Audits for Buildings 23 2.1 The need for an energy audit 24 2.2 The energybenchmarking method 25 2.2.1 Benchmarking step by step 25 2.2.2 How savings can be achieved 29 2.3 The degree-days concept 33 2.3.1 Regression of degree-day and energy consumption data 33 2.4 Energy Performance Certificates 34 2.5 Worked examples 36 2.6 Tutorial problems 43 3 Building Fabrics Heat Loss 45 3.1 Modes of heat transfer 46 3.2 Fouriers law of thermal conduction 46 3.2.1 Conduction through a planar wall 46 3.2.2 Radial conduction through a pipe wall 473.3 Heat transfer by convection 48 3.3.1 Convective heat transfer: experimental correlations 49 3.3.2 Free convection 50 3.3.3 Forced convection 50 3.4 Heat transfer through a composite wall separating two fluids 51 3.5 Heat exchangethrough a tube with convection on both sides 52 3.6 A composite tube with fluid on the inner and outer surfaces 53 3.7 Heat transfer by radiation 54 3.8 Building fabrics heat load calculations 55 3.9 Energy efficiency and the environment 57 3.9.1 Space heating 57 3.9.2 Insulation standards 58 3.9.3 The economics of heating 58 3.10 Worked examples 60 3.11 Tutorial problems 67 4 Ventilation 69 4.1 Aims of ventilation 70 4.2 Air quality 70 4.2.1 Minimum fresh air requirements 71 4.2.2 Composition of respired air 71 4.3 Ventilation methods 73 4.3.1 Natural ventilation 74 4.3.2 Mechanical or forced ventilation 75 4.4 Ventilation flow calculations 76 4.4.1 Volume flow calculations 76 4.4.2 Ventilation heat load calculations 76 4.4.3 Ventilation calculations based on CO2 build-up 76 4.5 Fans 77 4.5.1 Fan laws 78 4.5.2 Selection of fans 78 4.5.3 Calculation of ventilation fan duty 79 4.5.4 Pressure drop calculation 79 4.5.5 Energy efficiency in ventilation systems 81 4.6 Worked examples 82 4.7 Tutorial problems 91 4.8 Case Study: The National Trusts ventilation system 92 5 Heat Gains in Buildings 99 5.1 Introduction 100 5.2 Lighting 100 5.2.1 Lighting criteria 100 5.2.2 Lighting terminology 101 5.2.3 Measurement of light intensity 102 5.2.4 Types of lamp 102 5.3 Energy-saving measures for lighting 104 5.4 Casualheat gains from appliances 105 5.5 Occupants heat gains 106 5.6 Worked examples 106 5.7 Tutorial problems 110 5.8 Case Study: Calculation of heating load for a building options 111 6 Thermal Comfort 1
- ISBN: 978-0-470-65608-2
- Editorial: John Wiley & Sons
- Encuadernacion: Rústica
- Páginas: 320
- Fecha Publicación: 09/09/2011
- Nº Volúmenes: 1
- Idioma: Inglés