Department of Mechanical and Aerospace Engineering Solar Charged Electric Farming Tractors Author: Konstantinos Michail Akritidis Supervisor: Dr. Paul Tuohy A thesis submitted in partial fulfilment for the requirement of degree in Master of Science in Advanced Mechanical Engineering 2015 Copyright Declaration This thesis is the result of the author’s original research. It has been composed by the author and has not been previously submitted for examination which has led to the award of a degree. The copyright of this thesis belongs to the author under the terms of the United Kingdom Copyright Acts as qualified by University of Strathclyde Regulation 3.50. Due acknowledgement must always be made of the use of any material contained in, or derived from, this thesis. Signed: Konstantinos Michail Akritidis Date: 30/8/2015 2 Acknowledgements I would like to thank my wife, Natalie, for being supportive in this tough year, without her nothing would be possible, my family for all these years of devotion and support and of course Dr. Paul Tuohy for all his guidance and cooperation. I would like to extend my thanks to my classmates and colleagues for making this year more enjoyable. This thesis is devoted to my new-born son Nicolas. 3 Contents Acknowledgements ........................................................................................................ 3 Table of Figures ............................................................................................................. 7 List of tables ................................................................................................................... 9 Nomenclature ............................................................................................................... 10 Abstract ........................................................................................................................ 12 1. Introduction .............................................................................................................. 13 1.1. Farming Tractors ............................................................................................... 13 1.1.1 Farming tractors and agricultural mechanisation index .............................. 13 1.1.2 Power output of Tractors and PTO ............................................................. 15 1.2. Solar radiation ................................................................................................... 16 1.2.1. The Photovoltaic effect .............................................................................. 18 1.2.2. Solar Photovoltaic panels ........................................................................... 18 1.3. Energy Storage .................................................................................................. 19 1.3.1. Batteries ..................................................................................................... 19 1.3.2. Battery performance and degradation facts ............................................... 20 1.4. Electric Motors .................................................................................................. 21 1.5. Important notifications ...................................................................................... 22 2. Methodology of the project ...................................................................................... 23 2.1. Methodology flow chart .................................................................................... 23 2.2. Background ....................................................................................................... 24 2.3. Mathematics of the crop energy analysis method ............................................. 24 2.4. Case study ......................................................................................................... 24 2.5. Financial analysis .............................................................................................. 24 2.6. Environmental issues ........................................................................................ 25 2.7. Conclusion and discussion ................................................................................ 25 3. Back ground and Literature Review of the Project ................................................. 26 4 3.1. Literature Review .............................................................................................. 26 3.1. Thessaloniki and solar data ............................................................................... 27 3.2. Software Review ............................................................................................... 30 3.2.1. Homer Pro .................................................................................................. 30 3.2.2. Ret Screen .................................................................................................. 30 3.2.3. Merit ........................................................................................................... 31 3.2.4. PVsyst ........................................................................................................ 31 3.2.5. The Spreadsheet ......................................................................................... 31 3.3. Basic schematic representation of the proposed system ................................... 31 3.4. Existing Solar chargers for EV ......................................................................... 33 3.4.1. Solar PV cell types ..................................................................................... 34 3.4.2. Solar Generation Capacity and Feed in Tariff ............................................... 35 3.5. Basics of Electric and Diesel Motors ................................................................ 35 3.6. Lithium Ion Batteries ........................................................................................ 38 3.7. Environmental Reports and Policies ................................................................. 39 4. Crop Energy Analysis Method ................................................................................. 40 4.1. Mathematics, Functions and Indicative Examples ............................................ 40 4.1.1. Calendar of planned farming activities ...................................................... 44 4.1.2. Further energy analysis for each crop ........................................................ 46 5. Case Studies ............................................................................................................. 47 5.1. Types of crops and number of acres ................................................................. 47 5.2. Farming tools specifications and diesel engine power requirement ................. 47 5.3. The engine matching ......................................................................................... 51 5.4. The energy capacity and size of the battery ...................................................... 56 5.4.1. Battery degradation .................................................................................... 57 5.5. Solar Generation Schemes ................................................................................ 58 5.5.1. 3kW installed capacity ........................................................................... 59 5 5.5.2. 5kW installed capacity ........................................................................... 60 5.5.3. 10 kW installed capacity ........................................................................ 61 5.6. Daily demand and generation matching ........................................................ 62 5.7. Flexible demand and generation matching .................................................... 63 5.8. Days with relatively less solar radiation ....................................................... 67 5.9. Conclusions ................................................................................................... 70 6. Financial Analysis .................................................................................................... 72 6.1 Methodology ...................................................................................................... 72 6.2. Parameters taken into consideration ................................................................. 72 6.2.1. Cost of the electric tractor .......................................................................... 73 6.2.2. Cost of the solar array of 10 kW capacity .................................................. 73 6.2.3. Revenue from the crops ............................................................................. 74 6.2.4. Lifetime of the project ............................................................................... 75 6.2.5. No subsidy for crops .................................................................................. 75 6.2.6. Feed in Tariff (Greece) .............................................................................. 75 6.2.7. IRR ............................................................................................................. 76 6.3. Analysis of the model ....................................................................................... 77 6.3.1. CAPEX and OPEX .................................................................................... 78 6.3.2. Energy & crops prices and revenues .......................................................... 79 6.3.3. Debt ...........................................................................................................