Evaluating a Power Supply System for a Small-Scale Cocoa Processing Plant A Multi-Criteria Decision Analysis Approach Alexander Rothoff 2018 Student thesis, Master degree (one year), 15 HE Decision, Risk and Policy Analysis Master Programme in Decision, Risk and Policy Analysis Supervisor: Fredrik Bökman Examiner: Ulla Ahonen-Jonnarth Evaluating a Power Supply System for a Small-Scale Cocoa Processing Plant A Multi-Criteria Decision Analysis Approach by Alexander Rothoff Faculty of Engineering and Sustainable Development University of Gävle S-801 76 Gävle, Sweden Email: [email protected] Abstract The global supply and demand of energy is facing different challenges. On one hand an increasing energy demand, foremost in developing countries, and an increasing pressure on reaching climate goals changes the requirements on the design of power supply systems. This may be particularly relevant in terms of decentralized energy solutions and hybrid systems that incorporates renewable energy sources. This study exemplifies the use of multi-criteria decision analysis (MCDA) to evaluate different power supply alternatives for a small-scale cocoa processing plant (SSCPP), placed in Côte d´Ivoire. MCDA is an analytical approach to evaluate decision alternatives according to certain criteria, with the aim to find a preferred alternative. The function of a cocoa processing plant depends highly on its power supply. This study has been performed by first analysing the energy needs of the processing plant, which includes electricity, heating and cooling. Based on those specific energy needs different power supply alternatives have been created. In a following evaluation it has been exemplified how MCDA can be used within the energy sector to evaluate different alternatives. Within this exemplifying evaluation, following power supply solutions have been considered: power grid, power grid with back-up generator, power grid with LPG-heating (Liquified Petroleum Gas), power grid with solar energy, off-grid solar system with back-up generator and an off-grid generator with heat exchanger. The evaluation of alternatives has been made by using the three evaluation attributes: levelized cost of energy (LCOE), loss of load hours (LOLH) and carbon footprint of energy (CFOE). Contents Abbreviations and Terminology ................................................................................. 1 1 Introduction .............................................................................................................. 2 1.1 The Aim ........................................................................................................................... 3 1.2 Content and Structure ...................................................................................................... 4 1.3 Terms and Expressions .................................................................................................... 4 1.4 Conditions ....................................................................................................................... 5 1.5 Assumptions and estimations .......................................................................................... 5 1.6 The Author ...................................................................................................................... 6 2 The Cocoa Industry ................................................................................................. 7 2.1 The Cocoa Value Chain ................................................................................................... 7 2.2 Small Scale Cocoa Processing Plant................................................................................ 8 3 Methods .................................................................................................................. 10 3.1 Multi-Criteria Decision Analysis ................................................................................... 10 3.1.1 MCDA Approaches ............................................................................................. 10 3.1.2 Evaluation of Consequences ............................................................................... 13 3.1.3 How MCDA has been used in this thesis ............................................................ 16 3.2 Energy Analysis ............................................................................................................ 17 3.2.1 LCOE - Levelized Cost of Energy ....................................................................... 17 3.2.2 CFOE - Carbon Footprint of Energy.................................................................. 19 3.2.3 LOLH – Loss of Load Hours ............................................................................... 20 3.2.4 Solar power input ............................................................................................... 22 3.2.5 Energy and power demand ................................................................................. 24 3.3 Collection of information .............................................................................................. 25 4 Power Supply Requirements ................................................................................. 27 4.1 Target Requirements ..................................................................................................... 27 4.2 Energy Requirements .................................................................................................... 28 4.2.1 Drying ................................................................................................................. 29 4.2.2 De-hulling ........................................................................................................... 29 4.2.3 Roasting .............................................................................................................. 30 4.2.4 Grinding.............................................................................................................. 30 4.2.5 Tank storage and piping ..................................................................................... 31 4.2.6 Tempering, blocking and storage ....................................................................... 31 4.2.7 Summary of energy needs ................................................................................... 31 5 Objectives and Criteria ......................................................................................... 33 5.1 Cost................................................................................................................................ 35 5.1.1 Investment cost.................................................................................................... 35 5.1.2 Annual costs ........................................................................................................ 35 5.1.3 Lifetime ............................................................................................................... 35 5.2 Environmental Impact ................................................................................................... 36 5.3 Reliability ...................................................................................................................... 37 6 Power Supply Alternatives .................................................................................... 39 6.1 Alternative 1 .................................................................................................................. 40 6.2 Alternative 1b ................................................................................................................ 41 6.3 Alternative 2 .................................................................................................................. 42 6.4 Alternative 3 .................................................................................................................. 43 6.5 Alternative 4 .................................................................................................................. 45 6.6 Alternative 5 .................................................................................................................. 46 7 Consequences ......................................................................................................... 48 7.1 Levelized Cost of Energy (LCOE) ................................................................................ 48 7.1.1 Investment Cost ................................................................................................... 48 7.1.2 Annual Cost ........................................................................................................ 49 7.1.3 System Lifetime ................................................................................................... 50 7.1.4 LCOE values ....................................................................................................... 51 7.2 Carbon Footprint of Energy (CFOE) ............................................................................. 51 7.3 Loss of Load Hours (LOLH) ......................................................................................... 53 7.4 Summary of Consequences ........................................................................................... 54 8 Evaluation ............................................................................................................... 55 8.1 Utility values ................................................................................................................. 56 8.2 Weight assessment........................................................................................................