Solar Demonstration Lab Quarterly Update During 2015 the Cooperative released The Power of Solar as a learner s guide to the various technologies, brands and installation methods of solar power available. By the fall of 2015, the Cooperative commissioned a Solar Demonstration Lab to study various technologies, brands and installation methods of solar power. The Lab s first full year of production ended in 2016. A comprehensive report of that information is available for your review. This Quarterly Update, provides new information gained since the Cooperative released the Lab s 2016 report.
Table of Contents A. Updated Purchase Costs B. 2017 Quarterly kwh Production C. Updated Maintenance Issues D. Bankruptcies and Warranty Questions E. Executive Summary
Updates to Installation Costs? The buzz around the solar industry is that prices are continuing to fall. While this may be true in some cases, it is not always the case. We spoke to an experienced installer and asked the following question: If we were to start over and install the solar lab again today (about two years after the original installation), would there be a change in price? Answer (paraphrased): No. It would be about the same. There are occasional instances where we can get really good deals on solar panels, but they are short lived and the quotes we give our customers based on these deals are only good for a day or two. Otherwise, not much has changed. Conclusion: It does appear low cost panels from overseas markets are being cited as the cause of many of the American-based bankruptcies. There also appears to be an excess supply of solar panels which has also contributed to the price drops. U.S. companies are pushing back on imports* and if successful, the market price of solar cells and modules for U.S. developers will rise. *us.eversheds-sutherland.com/newscommentarysolar-industry-import-drama-continues
Table of Contents A. Updated Purchase Costs B. 2017 Quarterly kwh Production C. Updated Maintenance Issues D. Bankruptcies and Warranty Questions E. Executive Summary
Quarterly kwh Production Q1 2016 Q2 2017 Total: 39,205 kwh Array 2016 2017 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Array Total Single Axis Tracker 453 577 560 390 393 574 - - 2,946 Dual Axis Tracker 488 598 628 436 421 623 - - 3,194 Solar World - Fixed 398 486 472 345 343 479 - - 2,523 Suniva - Fixed 332 454 440 319 321 447 - - 2,312 Canadian Solar - Fixed 373 459 449 321 324 456 - - 2,382 Trina - Fixed 368 456 445 315 320 453 - - 2,358 tenksolar 3,533 4,773 4,654 2,962 3,033 4,534 - - 23,489 Lab Total 5,945 7,803 7,648 5,088 5,156 7,565 - - 39,205
Coincidental Peak Capacity Factor The chart below shows the percentage of full capacity at which each array was operating when our wholesale power provider, Arkansas Electric Cooperative Corporation (AECC), peaked. The peak tends to coincide more closely with central Arkansas weather than the weather in Carroll s territory. This can be problematic when it is cloudy in Carroll s territory, but hot and sunny across the rest of the state. 2016 to 2017 Comparison - June Year Day Time Weather Lab Average Capacity Factor 2016 23rd 5:00 PM Mostly Sunny 64% 2017 Date and Weather Conditions Month Day Time Weather June 14th 6:00 PM Scattered Clouds July - - - Aug. - - - Sept. - - - Array 2017 14th 6:00 PM Scattered Clouds 48% Coincidental Peak Capacity Factor 2015 2016 2017 Array Avg. June July Aug. Sept. June July Aug. Sept. June July Aug. Sept. Single Axis Tracker - 66% 71% 12% 77% 69% 85% 60% 64% - - - 63% Dual Axis Tracker - 73% 77% 13% 81% 71% 85% 62% 71% - - - 67% Solar World - Fixed - 40% 40% 10% 59% 55% 81% 42% 42% - - - 46% Suniva - Fixed - 30% 26% 8% 55% 50% 75% 40% 40% - - - 41% Canadian Solar - Fixed - 27% 27% 10% 53% 51% 78% 41% 41% - - - 41% Trina - Fixed - 32% 37% 10% 55% 52% 77% 40% 34% - - - 42% tenksolar - - - - 68% 62% 92% 46% 44% - - - 62% Lab Average - 45% 46% 11% 64% 59% 82% 47% 48% - - - 50%
Quarterly kwh Production Q1 2016 Q2 2017 Average Daily Solar Lab kwh Production per kw of Capacity Array 2016 2017 Array Avg. Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Single Axis Tracker 4.98 6.34 6.08 4.24 4.37 6.31 - - 5.39 Dual Axis Tracker 5.36 6.57 6.83 4.74 4.68 6.85 - - 5.84 Solar World - Fixed 4.37 5.34 5.13 3.75 3.82 5.26 - - 4.61 Suniva - Fixed 3.65 4.98 4.78 3.46 3.56 4.92 - - 4.23 Canadian Solar - Fixed 4.10 5.05 4.88 3.49 3.60 5.01 - - 4.35 Trina - Fixed 4.04 5.02 4.84 3.43 3.56 4.98 - - 4.31 tenksolar 4.31 5.83 5.62 3.58 3.74 5.54 - - 4.77 Lab Average 4.40 5.59 5.45 3.81 3.90 5.55 - - 4.79 To provide an apples to apples comparison, this table illustrates the performance of each system in the lab scaled to the same size 1 kw. Conclusion: The lab s performance for 1 kw falls short of the estimated number of hours available (at full capacity) for this region of the United States. Poor weather conditions most likely explain most of the shortfall in production during the Q1. As expected, production has increased from Q1 to Q2. However, three of the five fixed arrays in the lab are still underperforming based on the map s estimates (4.5 to 5.5 kwh). With two of the five fixed arrays operating within the map s range, one can conclude panel quality is the discerning factor. Note: Among the fixed arrays, panel manufacturer is the only variable.
Quarterly kwh Production vs. Same Quarter last year Array 2016 Q1 2017 Q1 Single Axis Tracker 453 393 Dual Axis Tracker 488 421 Solar World - Fixed 398 343 Suniva - Fixed 332 321 Canadian Solar - Fixed 373 324 Trina - Fixed 368 320 Number of Favorable Days (Partly Cloudy, Scattered Clouds, Clear) Number of Unfavorable Days (Mostly Cloudy, Overcast, Fog, Rain, Snow) Weather Conditions Jan Feb Mar Quarter 1 Jan Feb Mar Quarter 1 21 10 2016 2017 19 16 56 16 17 6 62% 43% 9 15 34 15 11 25 39 51 38% 57% Conclusion: Less favorable weather during Q1 2017 appears to be the primary contributor to the drop in production in Q1 2017. tenksolar 3,533 3,033 Lab Total 5,945 5,156 13% Decrease in kwh Production Total Days in Month/Quarter 31 28 31 90 31 28 31 90 100% 100% Array 2016 2017 Q2 Q2 Single Axis Tracker 577 574 Dual Axis Tracker 598 623 Solar World - Fixed 486 479 Suniva - Fixed 454 447 Canadian Solar - Fixed 459 456 Trina - Fixed 456 453 tenksolar 4,773 4,534 Lab Total 7,803 7,565 3% Decrease in kwh Production Number of Favorable Days (Partly Cloudy, Scattered Clouds, Clear) Number of Unfavorable Days (Mostly Cloudy, Overcast, Fog, Rain, Snow) Weather Conditions 2016 2017 Apr May Jun Quarter 2 Apr May Jun Quarter 2 18 15 18 51 15 18 19 52 12 16 12 40 15 56% 57% 13 11 39 44% 43% Total Days in Month/Quarter 30 31 30 91 30 31 30 91 100% 100% Conclusion: Production varied, but the weather was slightly more favorable during Q2 of 2017. The larger variances are primarily due to maintenance issue #3, #4, and #6. Also, panel degradation could have played a small role.
Weather and Maintenance Issues 3, 4, and 6 The weather during Q2 2016 and Q2 2017 was similar. Most individual system production data correlates with the weather data. There was a small drop in production from 2016 to 2017. This is presumed to be due to panel degradation. Discrepancies in the weather to production correlation are discussed below. Maintenance Issues 3 and 4: The dual axis tracker experienced an inverter failure (Issue 3) and intermittent tracking failure (Issue 4) in Q2 2016. No maintenance issues occurred in Q2 2017 and production was higher. Quarterly Solar Lab kwh Production Array 2016 2017 Q2 Q2 Single Axis Tracker 577 574 Dual Axis Tracker 598 623 Maintenance Issue 6: It was originally assumed that no production was lost due to this panel failure because the DC to AC ratio of the tenksolar system is so high (1.28 to 1.00). However, anytime the system was not producing at full AC capacity, there was room for the power that would have been produced by the failed panel. Solar World - Fixed 486 479 Suniva - Fixed 454 447 Canadian Solar - Fixed 459 456 Trina - Fixed 456 453 tenksolar 4,773 4,534 May 25, 2017 Lab Total 7,803 7,565
Table of Contents A. Updated Purchase Costs B. 2017 Quarterly kwh Production C. Updated Maintenance Issues D. Bankruptcies and Warranty Questions E. Executive Summary
Issue #2: Intermittent drops in production. Resolution: Version 3 of inverters installed. Status: Appears to be resolved. Cost: No out of pocket costs. Diagnosis/management time. Lost production: Estimated 200 kwh Maintenance Issues Issue #3: Inverter Failure. Resolution: Replacement inverter. Status: Appears to be resolved. Cost: Installer did not charge for labor. Approx. two hours of diagnosis/management time. Lost production: Estimated 38 kwh Issue #6: Panel Failure. Resolution: Replaced Panel. NEW Status: Resolved. Cost: No out of pocket costs. Lost production: 194 kwh Ratio with all panels functioning: 1.28 Ratio with one panel failure: 1.23 Issue #1: Low Production. (Suniva) Resolution: Replacement panels. Status: Appears to be resolved. Cost: $322 of labor to reinstall. Diagnosis/management time. Lost production: Estimated 72 kwh Issue #4: Intermittent Tracker Failure. Resolution: Maintenance Call, Reprogram Controls, Continue Monitoring. Status: Appears to be resolved. Cost: Approx. 4 hours of diagnosis/management time. Lost production: Estimated 7 kwh Issue #5: Inverter Failure. Resolution: Replacement inverter. Status: Appears to be resolved. Cost: Labor - unknown. Approx. two hours of diagnosis/management time. Lost production: Estimated 42 kwh from 4/5/2017 thru 5/3/17.
Maintenance Issue #6 On June 9, 2017, routine maintenance was conducted in the Solar Lab. The trackers were greased, and the LED indicator lights on the tenksolar system were checked. Panels: A single green flash indicates the panel is working properly. Inverters: A steady green light indicates the inverter is working properly. All panels and inverters were found to be in working order, except one panel. The indicator light was inactive. All breakers and connections were Good Panel: Amperage increased (0.06) from one side of the connection to the other. Bad Panel: Amperage did not increase from one side of the connection to the other. checked and found to be in good condition. A call to the installer was placed. He recommended taking amperage readings to confirm the panel was bad. The readings were taken and the panel was confirmed to be bad. The panel was replaced by the installer the following Tuesday, June 13, 2017.
Issue Maintenance Issues Failed Component In-Service Date Detection Date Estimated Lost Production #1 Panels July 15, 2015 November 15, 2015 72 kwh Ease of Detection Panels were obviously producing less than other Lab panels. Once contact was finally made with the manufacturer, they were able to confirm the underperformance. Delivery of freight-damaged replacement panels extended this resolution. Cooperative Hours to Resolve Event 60 #2 Version 1 Inverter Version 2 Inverter October 15, 2015 November 1, 2015 200 kwh Several rounds of detection and debate with the supplier extended the resolution of this issue over a 116-day period. Following the installation of the third version of inverters, the intermittent failures subsided. However, close monitoring of real-time production data was required to resolve this issue. 325 (see next page) #3 Inverter July 15, 2015 March 28, 2016 38 kwh Discovered via production monitoring system. Also, an automated email was sent from the inverter manufacturer. 2 #4 Tracker July 15, 2015 June 5, 2016 7 kwh Discovered via production monitoring system and a 16 visual inspection. #5 Inverter July 15, 2015 April 5, 2017 42 kwh #6 Panel October 15, 2015 June 9, 2017 194 kwh Discovered via production monitoring system. Also, an automated email was sent from the inverter manufacturer. Each panel has an indicator light that must be visually checked. One must walk across the panels to see the lights. 4 3 Conclusions: 1. Maintenance issues appear to be likely, even for a new system. 2. Closely monitoring the production of a solar system will help detect maintenance issues as they arise. 3. A valid long-term warranty is an important element to owning and operating a solar system.
tenksolar Maintenance Issues A recent article published by Green Tech Media* has provided insight into tenksolar s failures. Key Take-Aways According to a source for the article, tenksolar operated their inverters outside the inverter manufacturer s (APSystems) prescribed parameters. Inverters at over 100 installation sites had to be reprogrammed. According to the article, inverters manufactured by LeadSolar experienced catastrophic potting failures. Potting helps protect the inverter from the elements. It is important to note, tenksolar and LeadSolar** dispute Green Tech Media s conclusion within this article but do not offer any additional insight for the multiple inverter problems experienced in the lab. *GTM (Green Tech Media) who provides analysis for investors in the solar industry. Read the Full Article Here https://www.greentechmedia.com/articles/read/sources-ten-k-solar-winding-down-operations-after-a-series-of-field-failure **As a current employee of LeadSolar and a former employee of TenK Solar, I can definitely say that their problems were NOT primarily based on "disastrous field failures" due to "catastrophic potting failures" of the LeadSolar microinverters. LeadSolar has been a valued supplier to TenK for most of their history. The potting issues raised were limited in scope and were being addressed through mutually agreed upon corrective actions. These facts were confirmed by TenK in a recent statement. I believe that if you dig a bit deeper you will find that the current level of frustration among the customer base is due predominately to the abrupt announcement by TenK of its closure, with no advance notice to key customers, and no clear plan of support for moving forward. LeadSolar is working diligently with TenK s customer base to fill this void. We have agreed to continue the manufacture of microinverters for TenK systems and are dealing directly with TenK customers regarding warranty issues. This is a difficult situation for LeadSolar as well. The original intent of our relationship was for LeadSolar to focus on the integrity of our product, with TenK responsible for any customer or system-related issues. We now find ourselves in a position of being asked to support warranty issues of a much greater scope than originally intended. We will endeavor to do this to the best of our abilities. We ask only that TenK customer s be patient with us as we work through this difficult situation. Philip Benguhe General Manager- North America Operations LeadSolar Energy
Table of Contents A. Updated Purchase Costs B. 2017 Quarterly kwh Production C. Updated Maintenance Issues D. Bankruptcies and Warranty Questions E. Executive Summary
Bankruptcies and Warranty Questions SolarWorld AG, the parent company of SolarWorld Americas, has entered INSOLVENCY (being in a state that prompts one to file for bankruptcy). http://dailycaller.com/2017/05/11/largest-us-solar-panel-maker-files-for-bankruptcy-after-receiving-206- million-in-subsidies/ Suniva filed a voluntary CHAPTER 11 PETITION FOR RELIEF UNDER THE U.S. BANKRUPTCY CODE. http://www.renewableenergyworld.com/articles/2017/04/solar-module-manufacturer-suniva-files-forbankruptcy.html https://www.fool.com/investing/2017/07/01/the-1-thing-that-should-keep-solar-investors-up-at.aspx tenksolar: The Cooperative was recently notified by tenksolar s installer/distributer of tenksolar s CEASED FURTHER OPERATIONS. https://www.greentechmedia.com/articles/read/sources-ten-k-solar-winding-down-operations-after-aseries-of-field-failure ADDITIONAL recent solar industry bankruptcies include, but are not limited to the following: http://solarindustrymag.com/u-s-manufacturer-ten-k-solar-discontinuing-current-operation Enphase and other significant manufacturers of solar microinverters are facing serious competition and possible technology obsolescence. This is raising questions about Enphase s long-term viability. https://www.fool.com/investing/2017/04/18/solar-shake-up-why-more-bankruptcies-are-coming-in.aspx https://www.pv-magazine.com/2017/06/30/enphase-threatened-with-de-listing-due-to-low-stock-price/ Even more breathtaking is this https://www.greentechmedia.com/articles/read/the-mercifullyshort-list-of-fallen-solar-companies-2015-edition
??? What does this all mean for the Solar Demonstration Lab? What questions should we ask? Will another company pick up the bankrupt companies technology and honor existing warranties? Conclusions: 1. No easy answers to these questions exist. 2. It is impossible to know which companies, if any, will be in business throughout the warranty period.
Table of Contents A. Updated Purchase Costs B. 2017 Quarterly kwh Production C. Updated Maintenance Issues D. Bankruptcies and Warranty Questions E. Executive Summary
Executive Summary Technology Single Axis Tracker Dual Axis Tracker Fixed Panel Panel Brand Inverter Brand Maintenance Issues Solar World Enphase (See issues 3 and 5) Solar World Enphase Issue # 3 Issue # 4 Issue # 5 Solar World Enphase (See issues 3 and 5) Suniva Enphase Issue # 1 (See issues 3 and 5) Canadian Solar Enphase (See issues 3 and 5) Trina Enphase (See issues 3 and 5) tenksolar tenksolar tenksolar Issue #2 Issue #6 Panel/Inverter Warranty Bankruptcy and Warranty Questions Recovery of Investment 25/25 years 45 years 2060 25/25 years 52 years 2067 25/25 years 37 years 2052 25/25 years 41 years 2056 30/25 years 38 years 2053 25/25 years 38 years 2053 25/25 years 29 years 2044
Want More Information? For more detailed information about the Solar Demonstration Lab, click on the link below to see our 2016 report. http://www.carrollecc.com/files/solar/solar_lab_report.pdf For more general information about solar power, click on the following link. http://www.carrollecc.com/files/solar/the_power_of_solar_energy_12_13_16.pdf 20
Questions? Joey Magnini Carroll Electric Cooperative Corp. 800-432-9720, ext. 1306 jmagnini@carrollecc.com 21