Report on Forecasting, Concept of Renewable Energy Management Centres and Grid Balancing
Total Page:16
File Type:pdf, Size:1020Kb
1. GIZ - India Green Energy Corridors IGEN-GEC Report on Forecasting, Concept of Renewable Energy Management Centres and Grid Balancing Published by Consortium Partners University of Oldenburg, Germany Fraunhofer IWES, Germany FICHTNER GmbH & Co. KG, Germany Ernst & Young LLP, India Table of Contents Table of Contents 1 Table of Figures 3 List of Tables 4 List of Abbreviations 5 Executive Summary 6 1 Introduction 9 2 Overview of the Work Package 10 3 Wind & Solar Power Forecasting Infrastructure and Requirements 11 3.1 Existing Infrastructure and Practices for RE Forecasting in India 11 3.1.1 Operational Wind and Solar Power Forecasting in India Today 11 3.1.2 Operational Numerical Weather Prediction System of IMD 12 3.1.3 Role of Forecasting in New Regulation issued by CERC 14 3.1.4 Comments on Current Practice of Load Forecasting 15 3.2 State of the Art Operational Wind and Solar Power Forecasting 17 3.2.1 Overview 17 3.2.2 Numerical Weather Prediction 18 3.2.3 Measure of Accuracy of Wind and Solar Power Forecast 19 3.2.4 Wind Power Forecasting 21 3.2.5 Solar Power Forecasting 28 3.3 The Australian Wind Energy Forecasting System as reference implementation for India 38 3.3.1 Anemos wind power prediction platform 39 3.3.2 Extreme event warnings 41 3.3.3 Experience 41 3.4 Wind and Solar Power Forecasting Practice in Germany 44 3.5 Recommendations for Wind & Solar Power and Load Forecasting in India 46 4 Establishment of Renewable Energy Management Centres (REMC) 49 5 Balancing Capability Enhancement 52 5.1 Methodology and Introduction 52 5.1.1 Introduction 52 5.1.2 Methodology 53 6 Enhancing Balancing Capacity 54 6.1.1 Wrap-up of interview phase in India 54 6.1.2 Introduction 54 6.1.3 State perspective 54 6.1.4 Central perspective 59 1 | P a g e 6.1.5 Assessment of existing balancing capacity 61 6.1.6 Flexibility of power plants – literature overview 61 6.1.7 Turndown capability in India 61 6.1.8 Theoretical thermal balancing and ramping potential 62 6.1.9 Theoretical hydro balancing potential 65 6.1.10 Conclusion 65 6.1.11 Short-term solutions 66 6.1.12 Mid-term solutions 70 6.1.13 Long-term solutions 75 7 Cost analysis of balancing options 78 7.1.1 Regional balancing 78 7.1.2 Retrofitting 78 7.1.3 Storage options 79 8 Summary and Recommendations 82 8.1.1 Main outcomes and recommendations 82 9 Overall Strategy Roadmap & Recommendations 84 9.1 Summary of the strategy and the recommendations of all three work packages 84 Annexures 86 References 87 2 | P a g e Table of Figures Figure 1 - Outer and inner domain of the WRF model at 27 km and 9 km ........................................... 13 Figure 2 - WRF model domains with 3 km horizontal resolution at Regional Centres ......................... 14 Figure 3 - Typical pattern of geographical diversity for the daily load curve in the N, W, and S states of India on a single day (29 March 2014) .................................................................................................. 16 Figure 4: Wind power forecasting time scale ........................................................................................ 21 Figure 5: Temporal development of the one-day forecast error in the German control area of ‘E.On Netz’(blue) and for Germany (red) ........................................................................................................ 23 Figure 6: Very high resolution model domains, left: UM-4km (grey shaded area, UK Met Office, 70 vertical layers), right: COSMO-DE (DWD, 50 vertical layers). .............................................................. 24 Figure 7: Table of Wind power software models with international operation ...................................... 26 Figure 8 : Example of a ramp event following a shut-down due to high wind speeds .......................... 28 Figure 9: Forecasting methods used for different spatial and temporal scales .................................... 29 Figure 10: Overview of a regional PV power production scheme ......................................................... 29 Figure 11: Shortest-term forecasting scheme using cloud index images. ............................................ 32 Figure 12: Example of nested domains used in the WRF model......................................................... 34 Figure 13: Derivation of global irradiance on tilted surfaces from global horizontal irradiance. ........... 35 Figure 14: Forecast of global irradiance ............................................................................................... 37 Figure 15: RMSE of five forecasting approaches and persistence for three German stations for the first three forecast days. (1)–(3): different global models plus post-processing, (4)–(5): ............................ 37 Figure 16: Absolute (left) and relative (right) forecast errors ................................................................ 38 Figure 17: Indian wind farm example .................................................................................................... 39 Figure 18: Simplified flow chart of the Anemos short-term model chain (0-72 h) ................................. 40 Figure 19: Anemos. Live GUI for forecasts visualization ...................................................................... 40 Figure 20: Visualization example .......................................................................................................... 42 Figure 21: Example for the platform surveillance processes: Monitoring of SCADA data feed quality. .............................................................................................................................................................. 43 Figure 22 - Proposal of a load forecasting framework .......................................................................... 48 Figure 23: Focus of report and distinction between short-term (frequency control) and long-term balancing (scheduling) .......................................................................................................................... 52 Figure 24: Installed capacity and capacity penetration of RE in the analyzed states in India in 2014 . 54 Figure 25: Minimum load of power plants in Gujarat ............................................................................ 62 Figure 26: Total theoretical balancing potential for each state and comparison to installed RE capacity .............................................................................................................................................................. 63 Figure 27: Theoretical thermal balancing potential in RE rich-states compared to the potential of regions and all India ........................................................................................................................................... 63 Figure 28: Theoretical state wise ramping potential of all thermal power plants (left) and ramping demand in Gujarat (right) ...................................................................................................................... 64 Figure 29: Installed capacity ................................................................................................................. 65 Figure 30: Theoretical thermal balancing capability of RE-rich states today and up to 2022 ............... 66 Figure 31: Forecasting quality of three selected DISCOMs in 2014 ..................................................... 67 Figure 32: Overview of natural gas sector in India................................................................................ 70 Figure 33: Storage capacity .................................................................................................................. 71 Figure 34: Thermal Balancing Potential – Comparison between states, regions and India ................. 72 Figure 35: Potential and installed capacity of pump hydro storage in India ........................................ 73 Figure 36: Increase of transmission capacity under the Green Energy Corridor Project Plans ........... 74 Figure 37: Smoothing effects of wind energy supply from RE due to geographical diversification ...... 75 Figure 38: Overview of storage options and their typical storage capacity and possible cycle durationSource: Sterner/Stadler 2014 .................................................................................................. 76 Figure 39: Cost estimates of retrofitting gas turbines in single cycle and combined cycle plants ........ 79 Figure 40: Cost of electric load shifting for different storage options .................................................... 80 3 | P a g e List of Tables Table 1: Challenges for balancing and integrating RE in India – state perspective ............................. 58 Table 2: Problems in respect to grid operation and challenges of RE integration – central perspective .............................................................................................................................................................. 60 Table 3: Overview of flexibility parameters of power plants to be found in literature (international practice today / state-of-the-art) ......................................................................................................................... 61 Table 4: Starting capabilities of power plants ....................................................................................... 68 Table 5: Improvement potential ............................................................................................................ 70 Table 6: