ממירי העתיד - מעבר ל-99% נצילות

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ממירי העתיד - מעבר ל-99% נצילות

  1. 1. Large Scale PVSystemsBeyond the 99%EfficiencyTashtiot conference “MaximumRenewable Energy”, March 2012Lior Handelsman, VP ProductStrategy & BusinessDevelopment, Founder Website: www.solaredge.com Email: info@solaredge.com Twitter: www.twitter.com/SolarEdgePV Blog: www.solaredge.com/blog Facebook: www.facebook.com/solaredge ©2011 SolarEdge
  2. 2. Inverters – Beyond the 99% barrier In the last 10 years inverters have made huge advancement  Average efficiency went up from 86% to 96%  Average weight went down from 16 Kg/KWp to 5 Kg/KWp  Average price went down from 1.5 $/Wp to 0.35 $/Wp You can already see in the market inverters with 99% - 98% which is close to the theoretical limits Where can we go from here?? ©2011 SolarEdge 2
  3. 3. SystemOptimization ©2011 SolarEdge
  4. 4. Module Mismatch Impact on Power Loss Modules provide maximum power at specific optimal current and voltage Optimal current (Impp) depends on irradiance Optimal voltage (Vmpp) depends on temperature Modules exposed to different sunlight / temperature need different current and voltage to output maximum power  Traditional fields:  Modules: equal current  Strings: equal voltage V1 V1 V1 V1 I1 I1 … … … … … I1 Inverter ©2011 SolarEdge 4
  5. 5. Large Scale PV Plants - Design Perfectly designed large scale PV plants avoid shading, and strive to provide module uniformity ©2011 SolarEdge 5
  6. 6. Large Scale PV Plants - Reality  Can mismatch be completely avoided ?  Bottom: 20MW field in Rothenburg, Germany (1/3 of the field shown)  Right: actual I-V scatter plot of a 2MW sub-segment, between 4-9/2010.Source: B. Giesler et al., “Operating data analysis of various subsystems at the 20 MW PV power plant Rothenburg””,26th EUPVSEC, 5-9/9/11, Germany ©2011 SolarEdge 6
  7. 7. Temperature Derived Mismatch  German researchers* equipped a helicopter with an IR-camera  Temperature gradient found within a PV plant at operating conditions  13°C temperature decrease from the top module row to the bottom row (7.8m distance), due to convective heat transfer  4.3% Vmpp mismatch between top - bottom rows  ∆Vmpp=13°C * 0.33 [%/°C]  These strings will perform sub-optimally when parallelizedSource: C. Buerhop et al., ZAE Bayern, “The role of infrared emissivity of glass on IR-imaging of PV-plants”, 26th EUPVSEC, 5-9/9/11,Germany ©2011 SolarEdge 7
  8. 8. Mismatch Due to Soiling  Module soiling by dirt or bird droppings contributes to mismatch between modules and strings (beyond power loss due to sunlight blockage)  Soiling mismatch exposed by a SolarEdge monitoring system connected to the strings of a 700kW plant, installed flat on a winery roof in California:  Before:  After: cleaning the modules String mismatch due to increased power output by over uninterrupted soiling 30% (1MWh per day) (shade of blue = daily string energy)Source: SolarEdge Monitoring Portal. 700kW site monitored by SolarEdge String Monitoring Combiner Box (MCB), 7/2011 ©2011 SolarEdge 8
  9. 9. Mismatch Increase under Operating Conditions (2 years) Can PV investors assume 20% plant degradation by the 20th year, according to individual module guarantees?  Italian Research*: module degradation in 19MW & 13MW plants in Spain  785 modules flash tested before installation (2008), in 2009, and in 2010  Peak power decreases 1.0% - 3.5% in 2009, further 0.4% - 1.3% in 2010  Interestingly, the current drop exhibited a variance of up to 6%  Uneven module degradation rates increase the mismatch between the plant’s aging modules and reduce the plant performance beyond initial expectationSource: J. Coello, Enertis Solar, “Degradation of c-Si modules: a case study on 785 samples after two years under operation”,26th EUPVSEC, 5-9/9/11, Germany ©2011 SolarEdge 10
  10. 10. Mismatch Increase under Operating Conditions (20 years)  EU JRC’s research* analyzed degradation of 204 modules from 20 different manufacturers, following 19 - 23 years of outdoor exposure in Italy  82% of modules - high individual module quality: power > 80% after 20 yrs  But… power loss variance of identical modules reveals high mismatch, standard deviation > 5%, and in some cases 15%  Black lines: Power variance of identical modules after 20 yearsSource: A. Skoczek et. al., “The results of performance measurements of field-aged c-Si photovoltaic modules”, Prog. Photovolt: Res.Appl. 2009; 17:227–240 ©2011 SolarEdge 11
  11. 11. Mismatch - Summary Module mismatch challenges PV plant planners, installers and owners. Module heterogeneity sources:  Manufacturing tolerance  Temperature mismatch  Soiling mismatch  Undetected transport damage  Uneven module aging rate  Partial shading – inter-row, and cloud fronts Perfect site design, shading prevention, and even sorting by factory flash test reports cannot resolve mismatch power loss ©2011 SolarEdge 12
  12. 12. Large Field Optimization ©2011 SolarEdge
  13. 13. Solution 1: On-site Module Sorting  Research* reports on-site sorting of 2,800 modules in a 815kW plant, Italy  Random layout: Gaussian distribution of the Impp current, with three averages corresponding to manufacturing batches  Modules were re-sorted in homogenous strings  Added cost (design, re-sorting installation): 0.015-0.03 €/W depending on sorting tolerance  An increase of 0.5% in yield will offset the added cost  Re-sorting the modules does not protect against mismatch due to uneven aging unless repeated every several years of operationSource:P. Perotti et. al., “Monitoring and evaluation of economic impact in the reduction of mismatching in a PV plant located in NorthernItaly”, 26th EUPVSEC, 5-9/9/11, Germany ©2011 SolarEdge 14
  14. 14. Solution 2: Module-Level Optimization  As opposed to centralized Maximum Power Point (MPP) tracking, power optimizers perform MPP tracking at the module level  Mismatch loss is eliminated: each module operates at its individual optimal current and voltage, independently of other modules in the plant* Voltage 1 2 3 MismatchImpp 1 Current MismatchImpp 2 Vmpp 1 Vmpp 3 Inverter Source:H. Mann et. al., “Field Trial Results of Energy Maximizing Distributed DC Topology - Residential and Commercial Installations”, 25th EUPVSEC, 6-10/9/2010, Spain ©2011 SolarEdge 15
  15. 15. SolarEdge Module-Level Monitoring AdvantageAutomatic, accurate fault detection  Module-level performance monitoring  Faults located on site map  No additional wiring  Web and iPhone applications The Result:  Increased system availability and production:  Underperformance detected faster and more accurately  Operations and Maintenance cost reduction:  Remote diagnostics, reduced on-site troubleshooting Click to watch demo on:  Proactive customer service 16
  16. 16. Utility Scale Inverter +Module-level Optimizers ©2011 SolarEdge
  17. 17. Power Optimizers Drive Inverter Cost Down Utility scale inverter cost depends on its current limit Per given max current and cost, higher voltage = greater power Same 1,250Aac inverter, 1,250Aac inverter, + power optimizers with fixed without power optimizers string voltage Max Voc (dc) 1,000 V (by regulation) VDC (String voltage) 622 V – 773 V 920 V (20 x Suntech, Vmpp @ -5°C - +60°C) Fixed string voltage Nominal AC voltage 700 / √2 / 1.12 = 440 V 920 / √2 / 1.12= 580V assuming 12% AC fluctuations AC current limit (by inverter spec.) 1,250 A Max power output 440 * 1,250 * √3 = 0.96 MW 580 * 1,250 * √3 = 1.26 MW Inverter cost reduction / Watt 24% saving in $/W Assumptions  Inverter: SolarEdge SE1250K  Power optimizer: SolarEdge OP300-MV SolarEdge  Module: Suntech STP280 1250k ©2011 SolarEdge 18
  18. 18. Lower Input Current Rating –Further Cost Reduction Higher fixed string voltage enables lower input current rating - further saving Same 1,250Aac inverter, 1,250Aac inverter, + power optimizers with fixed without power optimizers string voltage VDC (String voltage) 622 V – 773 V 920 V (20 x Suntech, Vmpp @ -5°C - +60°C) Fixed string voltage Max power output 440 * 1,250 * √3 = 0.96 MW 580 * 1,250 * √3 = 1.26 MW Inverter cost reduction / Watt 24% saving in $/W Max input current rating 0.96 MW / 622 V = 1,540 A 1.26 MW / 920 V = 1,370 A Lower current rating required  1,370 / 1,540 = 11% saving in Further cost reduction enabled current related hardware Assumptions  Inverter: SolarEdge SE1250K  Power optimizer: SolarEdge OP300-MV SolarEdge  Module: Suntech STP280 1250k ©2011 SolarEdge 19
  19. 19. Lower Input Current –Wiring Loss Reduction Lower input current reduces wiring losses by 26% Same 1,250Aac inverter, 1,250Aac inverter, + power optimizers with fixed without power optimizers string voltage 920 V Nominal VDC (String voltage) 700 V Fixed string voltage Max power output 440 * 1,250 * √3 = 0.96 MW 580 * 1,250 * √3 = 1.26 MW Nominal IDC (String current) 0.96 MW / 700 V = 1,370 A = 1.26 MW / 920 V = 1,370A Warmer, sunnier days: 920 V 622 V (11% lower than 700V) Min VDC (String voltage) Fixed string voltage Max power output 0.85 MW 1.12 MW (Current * 11% lower Vmpp) Nominal IDC (String current) 0.85 MW / 1,370 A 1.12 MW / 920 V = 1,220 A Wiring power loss reduction 26% I1 2R / I2 2R = (1370/1220)2 Assumptions  Inverter: SolarEdge SE1250K SolarEdge  Power optimizer: SolarEdge OP300-MV 1250k  Module: Suntech STP280 20 ©2011 SolarEdge
  20. 20. SolarEdge at a Glance Founded in 2006 5 kW Czech Republic Over 65 patents filed Offices in Israel, Germany, California, Japan and Italy Thousands of installations in 30 countries worldwide 50MW installed in 2010  150MW expected in 2011 End to end solution, for residential, commercial, and large scale PV site: 50 kW Israel  Power optimizers: module-level MPPT, monitoring, safety  Inverters: from 3kW to 1.25 MW  Monitoring portal: module-level, and string level iSuppli, Market Research Firm, 2/2011 900kW France  “SolarEdge has over 70% share of the optimizer market” Photon Magazine, test result, 10/2011  “additional yield in all scenarios, even when no shadows were cast”  “makes it easy to detect faulty modules – a task that can otherwise require a great deal of effort.”  “easy to install” ©2011 SolarEdge 21
  21. 21. >100MW installations in 2010-2011 900kW, France 250kW, Czech Republic 15kW, Israel 4kW, United Kingdom 22
  22. 22. European mid-size reference sites 900kW, France 250kW, Czech Republic50kW, Israel 200kW, Italy 250kW, France France 23
  23. 23. Thank you Website: www.solaredge.com Email: info@solaredge.com Twitter: www.twitter.com/SolarEdgePV Blog: www.solaredge.com/blog Facebook: www.facebook.com/solaredge ©2011 SolarEdge

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