Sunzest Solar

🤔 Are current PV modules and the state of their of sustainable/reliable/durable? 😤 No, not in the slightest. Both the financial stability of the PV module manufacturers and the quality of PV modules they produce is suffering. 📉 Trends in Altman Z scores as seen in Sinovoltaics Manufacturer Rankings (Downloadable for free) and PV Tech detailed analysis there of are very concerning and should be considered. 🥼 Both performance by ISO17025 labs and accelerated lifetime by RETC (Renewable Energy Test Center) or Kiwa PVEL tests (IV, EL, gel content/peel, Mechanical Load, UVID and PID) arent promising. 🕵♀️ Quality Assurance and Quality Control companies like Sinovoltaics are seeing more issues with incoming quality control of raw materials (amongst other solar PV cells), and poor calibration of machines (of which AI is used). 🏭 Various factories are cutting costs to keep their heads above water, which includes shutting down production lines or delaying maintenance/calibration of machines, extending the shelf life of stored materials all while heavily re-negotiating raw materials prices. 💲 As studied by SolarBankability David Moser the costs of poor quality can be up to 3.5 EUR/kWp per year. 💸 Cut your risks as Independent Power Producer or Solar PV asset owner. A 50MW project with smart contracts (including strict quality criteria), lab testing and factory audits may only cost between 0.03 - 0.08 EUR more but will save up to 3.5 EUR/kWp/year. 👀 Looking for an informed partner to help choose a negotiate quality criteria on your behalf? or conduct factory audits and production monitoring? 📳 Contact Sunzest Solar for quality support or Benoit van der Maas for inspections. 🥸 See #SVInsider or #MicrocrackMonday for more insights in PV challenges. #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #solarcells #solartesting #quality #bankability #qualitycontrol #QC #kwh #reliability #solarbankability #TIER1 #altmanzscore

💡 Inspired by Stephen Chapman on my last post, astutely noting that the EL images were related to Potential Induced Degradation - I thought I'd touch on the topic. 👍 Comment, Like and Re-Post! 🤔 Isnt PID a thing of the past and now integrated as part of IEC61215 Certification? 😤 To an certain extent, yes, but its coming back with a vengeance according to RETC (Renewable Energy Test Center) in their latest PV Module Index Report a large percentage of modules had red flags losing more than 2.5% power) and there is a negative upward trend with PID, in which they see up to 13% loss due to PID, which is reiterated by Peter Hacke from National Renewable Energy Laboratory during EU PVSEC that PID-polarization stabilizes around 6%. 🧐 What is PID? PID is a critical failure mode affecting both monofacial and #bifacial (PID polarization) PV modules of the #PERC, #HJT and #TOPCON type. Considering that according to VDMA ITRPV these are the new upcoming technologies; this must be known and addressed. 🧲 PID polarization according to a great article by imec Eszter Voroshazi is often a temporary, but reversible degradation of the passivation layer, which reduces the performance due to a surface recombination increase. Intricate solar cell architectures like TOPCON and heterojunction (HTJ #SHJ) seem to be more sensitive to PID-p.  ⚡ PID shunting is a combination of ion drift (Na+ from glass) and high voltages (1500v) that cause cells to shunt. The effect of PID can be visible in #EL images as noted in my previous post. 😊 Good news is if this is monitored, tested and known - solar panel manufacturers can address this like they did with PERC LID when they shifted to Gallium doping and controlling hydrogenation. 🥼 Lab testing managed by parties like Sinovoltaics can help test for PID, by either conducting 96 hour or 196 hour IEC62804 PID testing (60 C + 85% RH and 1500 volts) to see the degree of PID. 👀 Looking for an informed partner to help choose a mitigate risks? 📳 Contact Sunzest Solar (#QAQC) or Benoit van der Maas (#inspections) #MicrocrackMonday #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #solarcells #solartesting #quality #bankability #qualitycontrol #QC #kwh #reliability #solarbankability #TIER1 #USA

🤔 Are you a developer, IPP or equity investor in solar PV with concerns about the financial strength of your PV module supplier with comments like " 9 cent/Wp are irrational prices" by Jinko Solar Co., Ltd. and Carlos León Worner - 卡洛斯 reports of solar panel manufacturers reporting losses & should address their profitability instead of market share? 😲 Are you also worried about the quality the modules now they are being sold under cost price? Are you looking beyond financial bankability? 👩🎓 Smart developers, IPP & Equity Investors are doing the following to ensure they can squeeze out every electron/kWh over the full lifespan of their project despite the technology challenges & market circumstances. 🤑 They look at Sinovoltaics Altman Z scores and the trend in the last 3 years, along with PV Tech Bankability Ratings - request the latest Dun & Bradstreet credit reports to start the discussion with your supplier. 📖 These parties read the latest literature on the polymers in PV modules and known degradation rates in PV cells via EU PVSEC papers like that of Gernot Oreski, the PEARL PV Group (Angele Reinders), IEA PVPS - Photovoltaic Power Systems Programme or UNSW on TOPCON/SHJ issues. 🚧 Making a risk map on how to mitigate these issues and how to mitigate them. ⛈ Or looking into using the Malte Ruben Vogt PhD paper on TMY data including UV, Temperature, Precipitation and Irradiance. Pulsar Power does your team integrate this? 🕵♂️ They execute factory audits & production monitoring, agreeing upon quality standards, contractually putting in third party testing and review. 👓 They broaden the definition of bankability to include a module that has 6 months of outdoor data, and has done third party accelerated lifetime testing and opting for that BOM, taking into account local site considerations that may accelerate degradation or failure modes. 💰 Instead of paying 9 cents, they pay a few more cents to test modules for IV, EL, gel content and some other tests to ensure its reliability & durability. 🧠 There are great papers like that of Joseph Kuitche @Govindasamy TamizhMani Arizona State University on what tests there may give some insight the 10 - 30 year lifetime, that isnt covered by the initial 5 - 10 year by the IEC61215/61730. Though more insights are needed. 👀 Looking for an informed partner to help choose a financial & technical bankable PV module and supplier? 📳 Contact Sunzest Solar (latest mitigation tactics & strategies for true bankability) or Benoit van der Maas from Sinovoltaics (factory/ESG audits or production monitoring). #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #solarcells #solartesting #quality #bankability

👍 Like, Re-post, comment! 🌞 Is the first year(s) 7% or more performance loss caused by UV Induced Degradation #UVID for #PERT/ #IBC/ #SHJ = 10 - 15% Light Induced Degradation #LID was for #PERC (now resolved with Gallium doping)? 👻 Isnt UVID addressed by smart selection of bill of materials? 🤔 Yes, to an extent it is mitigated with high UV cut off encapsulants; but UVID is a challenge that needs addressed to avoid yield losses. 🖨 As Radovan Kopecek from ISC Konstanz mentioned this also depends on the front and back cell structure deposition and (and quality thereof) though additional factors also play a role. 🏫 National Renewable Energy Laboratory along with Peter Hacke, David C. Miller Laura Schelhas @Archana Singh has a great paper on UVID (see link in the comments). The take aways are: 😵 SHJ suffered the most from UVID with ~5% loss per year and maximum 8% per year (Voc & FF loss). Meyer Burger Technology AG what smart approaches has your team taken to mitigate these losses? 🎒 SHJ loss could be attributed to Hydrogen concentrations as studied earlier by UNSW Catherine Chan Bram Hoex Chandany Sen and Alison Ciesla for PERC LID and #LETID. See their earlier paper on additional TOPCON concerns that should be addressed. 👩🎓 TNO has a paper from 2016 discussing UVID/PID-s free n-Pasha cells (PERT). Maciej K. Stodolny Bas Van Aken 😵 Backside of bifacial SHJ/PERT/IBC saw higher rates of degradation (up to 13%) vs 1 - 4% frontside; potentially due to the type of emitter and passivation schemes, SiNx thickness & Refractive Index. 😵 IBC cell showed an increase of power, despite 2% loss in Voc however the power loss depends if on the IBC cell architecture SBC, ABC, TBC. Aiko Energy keen to hear your insights and how your team has tackled this! 🚧 UVID Mitigation option: Encapsulants with a high UV cut-off 🚧 UVID Mitigation option: Glass Anti-reflection coatings that reduce UV absorption 🚧 UVID Mitigation option: Opting for cells with a more UV stable passivation type. 🚧 UVID Mitigation option: Opting for Ce+ solarization glass (though more expensive). ❗ Note TOPCon solar cell structure take the base structure of PERT, but replaces the back surface field with n+ Poly-Si layer. Though RETC (Renewable Energy Test Center) & Kiwa PVEL have seen a higher frequency of UVID issues with TOPCON solar panels. 🕵♀️ Have you as a developer or investor asked these questions to your PV module supplier or done risk probability assessments when using TOPCON, SHJ or IBC for your projects? 👀 Looking for an informed partner to help navitage and mitigate these UVID from affecting the yield of your solar parks? 📳 Contact Sunzest Solar (contract negotiations and QAQC strategies) or Sinovoltaics (factory/ESG audits or production monitoring). ® Picture from Kiwa PVEL #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #solarcells #solartesting #quality

🌞 How do bill of materials (encapsulant, backsheet and front sheet (glass) impact degradation or failure modes in different regions of the world as mentioned by Jan◾ Mastny? 👻 Arent PV modules ready for all climates? 🤔 To an extent it is, however some polymers are better suited than others for different climates. The IEC damp heat and thermal cycling tests are mainly to replicate temperate/continental climates, not tropical (hot & humid) and desert (arid) climates. 👍 Like, Re-post and comment! 🍸 There are various different thicknesses of glass to be chosen, 3.2 mm, 2 mm. They can also be tempered, semi-tempered or chemically tempered. The thickness and how they are tempered plays a role in their resilience towards wind loads, hail, snow loads and mechanical rigidity. 🧞♂️ There are various types of encapsulants available, those being EVA, white EVA, EPE, POE and TPO. TaiyangNews - All About Solar has some great reports on the market shares hereof and challenges. 🔍 All in all, the encapsulant should be chemically inert and have a high dielectric constant, high resistivity, low elastic modulus, low thermal oxidation coefficient, high light transmissivity >90% and resistant to UV light, suitable thermal expansion coefficients with high water resistance, and oxygen permeability. 🎶 Note! Not all polymers/encapsulants are made the same and performance/reliability can vary within the different groups. Gernot Oreski Polymer Competence Center Leoben GmbH (PCCL) has some great insights on this and is working on a POE overview. Also EVA is the cheapest alternative, then EPE, POE and then lastly TPO. Manufacturers look to balance costs, performance and reliability. 🎒 There are various different types of backsheets with varying levels of reliability/durability. Those being hashtag #PFAS family (Tedlar/Keynar) (TPT, KPK, KPE, TPE, KPC, TPP, TPC) or PET, CPC, ApPo, PPP. They have varying levels of also WVTR and resistivity, but also sensitivity to yellowing, cracking and hydrolysis. The balance is then not only performance, cost and reliability - but also future recyclability like options like Energyra Europe, Solarge. 👨🔧 Combinations like higher WVTR encapsulants + high WVTR backsheets could be a risk for PID and tropical locations. Mapping out these BOM combinations should be part of your #QAQC risk assessment even if IEC certified. ⚠ SHJ/+ #Perovskite tandem modules with very low WVTR encapsulants, and high UV resistance and low resistivity could be a major concern. As they are very sensitive to water and #UVID and due to the higher voltages more likely to suffer from #PID. 👀 Sunzest Solar and Sinovoltaics are your partners in helping you review these modules for performance, but also durability/durability. Mapping out the risks for the different BOM combinations (+ cell sensitivities). #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #solarplant #solarcells #solartesting

👍 Like, Re-post and comment! 🌞 If IEC61215 and IEC61730 only are an indicator of the first 5 - 10 years of performance/reliability, what should be asked to get insights on the 5 - 30 year durability or reliability? 👻 Don't warranties cover product and/or lifetime failures? 🤔 Yes, however the best warranty is the one you don't have to use. Claims are challenging, few companies will take accountability, they take long and are often settled outside of court (if at all). Note, that these certificates are often a bare minimum needed to pass (so getting details of how well a solar panel did gives more confidence). 🌍 The certificates or test scheme should be considered based on where the module is being placed (climate & windload), application (floating, agrivoltaics, ground, rooftop). 54% of manufactured in the solar panels often still failure TC200 or even DH1000 hour tests despite being certified according to International Energy Agency (IEA) PVPS. ⭐ Repeating even IEC61215/61730 tests (static or dynamic load), TC, DH just to verify. 📏 IEC62804 PID to see the level of impact of PID on the module. 🔨 IEC63209 Test Scheme or equivalent third party testing like that from RETC (Renewable Energy Test Center), Kiwa PVEL or manufacturer 3 x IEC tests like that of DH/TC or DuPont MAST, ATLAS® 25 year or other! less the 5% degradation is good, more is fail and less than 3$% is really good. 🌊 IEC61701 Salt Mist for those modules close to the sea. Note there are different grades so ask what grade was tested. 💩 IEC62716 Ammonia for those modules near pig/chicken or cow farms. Note there are different grades so ask what grade was tested. 📈 IEC63342 LETID as according to UNSW this is a problem for TOPCON and PERC. 🌶 IEC63126 High Temperature for locations with high temperature like deserts. This should include IEC62788 for sand Abrasion in this list. 🔬 It is critical to have a small batch (using IS2859) S2 or S3 levels to test for UVID/PID/wet Leakage or DH/TC testing. Or further testing depending on your budget, risk appetite and the location where the module is installed. 🤐 Note that EPCs only have 2 year warranties, O&M 3 - 5 year contracts, some developers sell before or after construction (or within 5 years) and IPPs own projects for the full lifetime and depend on the module to produce every electron it can. This is why parties like Straightforward BV and Pulsar Power are critical in helping you mitigate technical risks before, during or after construction. The risk per player varies and in turn how they mitigate them - discuss this with your Stakeholders. 👀 Look for Sunzest Solar and Sinovoltaics to be your partners in helping you test these modules for reliability and durability. #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarcells #solartesting

👍 Like, Re-post, comment! Your opinion and insights are well needed! 🌞 Are solar panels still a great sustainable & renewable investment and what is needed to make it excellent as a conversation starter. 👻 Arent solar PV modules hard to recycle have big carbon footprint? 🤔 Roughly 95 - 98% of the module is recyclable. Though various factors come into play if circularity and sustainability are your priority. Below is some literature (albeit some are outdated and would require an update). 👣 Glass-backsheet (glass-glass) modules produced in China, Germany or the EU are linked to CO2 emissions of 810 (750), 580 (520) and 480 (420) kg CO2- eq/kWp, respectively according to CO2 Emission of Si-PV modules - Impact of Module design and Production Location by Fraunhofer-Institut für Solare Energiesysteme ISE (2022). 🎯 Alternatively 💡 ~40 g CO2 eq/kWh life cycle greenhouse gases (GHG) LCA for solar PV vs ~1000 for coal as revised by National Renewable Energy Laboratory (2012) in Life Cycle Greenhouse Gas Emissions from Solar Photovoltaics (though dependent of solar irradiation, performance ratio, operating lifetime, module efficiency). Given this report is 12 years old, these numbers may have drastically changed. 📊 Energy payback time also depends on type of technology, location of manufacturing and insolation of the site according to U.S. Department of Energy (DOE) but is between 1 - 4 years. 🗑 160 million tones in solar PV waste worst case by 2050 vs 70,350 million tonnes of waste for municipal waste. The market is taking serious steps in reducing the waste - Colorado School of Mines. 📉 Energyra Europe and Solarge have even lower carbon footprints as they focus on recyclable polymers! Biosphere Solar is looking at the next generation of circular modules. 🔍 Parties like Sinovoltaics can not only do factory audits, but also Environmental Sustainable Governance (ESG) audits to determine GHG emissions and much more to determine the impact of the chosen module you opt for. The team also has some great blogs on a wide range of topics that I would highly recommend to read! 👀 Sunzest Solar for more insights. 😹 Keen to your expert insights and updated numbers! Bethany Willis Mariska de Wild-Scholten ☀️Evert Bende☀️ Benoit van der Maas Dricus de Rooij ☀️🔋Arthur Claire ☀️🔋Patrick Saat MSc. Dr. Debajyoti Sarangi Guy Vandendungen Elbert -Jan Achterberg Luigi Marras David Moser Radovan Kopecek Calin Sas M.Sc Dennis van der Meij Gerard Scheper Tor "Solar Fred" Valenza Niclas D. Weimar Chetan Singh Solanki Julija Kaladžinskaitė Marco Raugei Max Mittag Ferruccio Ferroni Robert Hopkirk Heather Mirletz Jessica Daaboul Patrick Moriarty Teresa Barnes Silvana Ovaitt Bonna Newman #ESG #enviromentalsustainabilitygovernance #solarpv #solarpower #kennisdelen #climatecrisis #wind #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #solarplant #solarcells #quality #circularity #sustainability

👍 Like, Re-post, comment! 🌞 How often do modules break and when they break what issues happen and how to determine how severe the issues are? 👻 Isn't the rate of module failure issues low? 🤔 Yes, it is looking at claims this is between 3 - 7% of all failure events during the lifetime of a project according to Sandia National Laboratories and public claim reports. 🎩 Of that 3 - 7% , what defects occur then during the lifetime of a project - according to Ulrike Jahn and Gernot Oreski are: 🏭 Manufacturing faults, severity and time frame 😵 LID - Low Frequency - Low Severity: First Year (PERC only)* 😵 UVLID - Medium Frequency - Medium Severity: First Years (TOPCON, IBC)* 😵 PID - Low-Medium Frequency - High Severity: First 5 years 😵 Hotspots - High Frequency + High Severity (may also occur due to shading) 😵 Glass Breakage - Medium - High Frequency + Medium - High Severity: First 2 years 😵 Encapsulation Discoloring - Medium - High Frequency + Low - Medium Severity: Year 7 onwards 😵 Discoloring of potant - High Frequency + Low Severity: Year 3 onwards 😵Defective bypass diode - Medium Frequency + Medium - High Severity: First 3 years 😵 AR Coating loss - Medium Frequency + Low - Medium Severity: After 3 years 😵 Burn Marks - Low Frequency - High Severity: First 7 years 😵 Minor Delamination - Low Frequency + Low Severity: First 10 years 😵 Major Delamination - Low Frequency + High Severity: After 12 years 😵 Fractured Cells: Medium Severity + Medium Severity: First 4 years 😵 Disconnected strings or interconnect breakage or discoloration: Medium - High Frequency - Medium Severity: Year 1 to 6 🏞 Weather and outdoor impacts 😵 Hail: Low Frequency + High Severity: first 5 years 😵 Birds (stone drops) - not noted but observed frequently from different site visits - Low Severity: All years* 😵 Storm: Low Frequency + Low Severity: All years: First year(s) 😵 Lightinging strike : Low Frequency + Low Severity: All years 😵 Animal bites: Low - Medium Frequency + Low - Medium Severity: First year(s) 😵 Soiling/shading - High Frequency + Medium - High Severity: First 7 years 😣 Severity determined by Sarah Kurtz, Michael Woodhouse and Dirk Jordan and International Energy Agency (IEA) PVPS team and DNV. ❗ The defects and their frequency depend heavily on manufacturing, installation, location, climate and operational/monitoring quality. 👀Looking for an informed partner to help navitage and mitigate these high frequency, high severity issues and avoid manufacturing defects? 📳 Contact Sunzest Solar (contract negotiations and QAQC strategies) or Sinovoltaics (factory/ESG audits or production monitoring). *not noted in the papers - integrated. #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #solarcells #solartesting #quality

👍 Like, Re-post and comment! 🌞 What do the climate crisis, wind loads and thermo-mechanical stresses of PV modules have to do with each other? 👻 Isnt the utility market looking at glass glass modules which have a stronger thermomechanical strength? 🤔 Yes, research shows that glass glass in combination with multibusbar or back contract reduce the impact of microcracks - though larger solar panels and thinner glass show a higher frequency of glass breakage. 📏 To reduce weight of the ultra-large format modules, thinner glass is being used (2mm). Heat strengthend instead of tempered it provides less compressive strength. Chemical treatment of the glass could be a alternative, but is more expensive. 🔨 RETC (Renewable Energy Test Center) and Kiwa PVEL and DurAMat Project are seeing a higher frequency of glass breakage. ☁ According to NSF NCAR - The National Center for Atmospheric Research winds will accelerate by about 2% for every degree Celsius that the world warms. KNMI - Royal Netherlands Meteorological Institute argues ont he region. Typically winds are higher along the coast (but even higher in warm regions like South Europe). 👨🔬 Technical advisors like Pulsar Power and Straightforward BV may consider higher wind loads for a given location to account for thermo-mechcanical stresses. 📚 The current theory is it is due to potentially manufacturing defects in the glass or module clamps being torqued down with too much force during installation combined with use of installation on short rails which cause modules to bend. Higher wind loads can play a future role as most wind like irradiation are based on last 20 year estimations for the future. 🕵♀️ IEC61215 commitees are most likely already discussing an update to accomodate these new ultra large module issues with focus on dynamic and static load tests and how they are mounted. Norms always lag behind the latest innovations by 2 - 4 years. ❗ imec has some work on thermo-mecahnical stresses of these large modules for different applications (including floating). 🏋♀️ Recommend doing site reviews + dynamic load testing in the same mounting style as considered for your site. 👀Looking for an informed partner to help navitage and mitigate these thermo-mechanical risks and other QAQC avoidance measures? 📳 Contact Sunzest Solar (contract negotiations and QAQC strategies) or Sinovoltaics (factory/ESG audits or production monitoring). #kennisdelen #climatecrisis #wind #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #solarcells #solartesting #quality

👍 Comment, re-post or like! 🌞 The questions sometimes pops up: with the shift towards TOPCON and SHJ/HJT, what technological concerns should we mitigate when opting for either given my last post on solar cell encapsulation requirements. 📚 For the latest and greatest on reliability (5 - 15 years) and durability (+15 year) failure modes and degradation rates: look at National Renewable Energy Laboratory Reliability Workshop, Angele Reinders TRUST PV, Teresa Barnes DurAMat Project, Karl-Anders Weiss Fraunhofer-Institut für Solare Energiesysteme ISE SOPHIA workshop or EU PVSEC, kWh Analytics Risk Assessment Report or EU SolarBankability or Peter Seidel Ingrid Repins PVQAT 👻  Doesn't the IEC61215/61730 and IEC62804 (PID) cover most of these concerns? 🤔 Unfortunately not. These certificates first need to be verified for the aimed for product, but know that certification is always lagging behind technological advancements. The last 10 years have seen huge leaps and jumps made (as seen in the NREL Martini Graph of changes). 🏭 Most certified test bodies have online platforms to verify the certificate of the solar PV module you re looking at. Good to always double check. 🔍 Various mitigation strategies and tactics exist - be it lab testing (Basic testing: IV, EL, Wet Leakage or advanced testing: PID, Backsheet, etc), IR/EL drones, UV Fluoresncence, RISO, String IV. 🖼 The picture gives some insight into what you can look to test if opting for these cell architectures, but will depend on how it is Encapsulant and where it is installed (and how). 🤓SolarPower Europe EPC Best Practices 2.0 gives a foundation to start from (AQL and types of tests), however does not yet reflect the latest technology developments. 👀Looking to adapt your QAQC and risks avoidance measures for these new technologies or factory audits to mitigate known production challenges? Contact Sunzest Solar or Sinovoltaics for their dedicated services. 👓 Keen to hear your expert opinions, insights, questions, conundrums, worries and headaches are on the matter. Michaël Daenen Niclas D. Weimar Benoit van der Maas Dricus de Rooij Arthur Claire ☀️🔋 ☀️Evert Bende☀️ Patrick Saat MSc. Dennis van der Meij Dr. Debajyoti Sarangi Tor "Solar Fred" Valenza Calin Sas M.Sc Radovan Kopecek Gerard Scheper Luigi Marras Guy Vandendungen Elbert -Jan Achterberg David Moser Peter Hacke Daniel Etschmann Emiel Ponte Eleonora Annigoni Sarah Kurtz Eszter Voroshazi Mauricio Richter Rios Wilfried Van Sark Jason Kaminsky Robert White #kennisdelen #solarenergy #solarpv #photovoltaics #solarpanels #pvmodules #solarphotovoltaics #QAQC #solarplant #solarpvplant #IEC #IEC61215 #solarcells #IEC63209 #solartesting