You have questions? We got the answers!
1. Innovation
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1.1. What is our present technical edge?
We are offering a unique technology of individual module monitoring, called SunSniffer, which is integrated in the junction boxes of solar modules, allowing 100% transparency on the performance and functioning of power plants thanks to real-time data collection from individual modules/strings and advanced artificial intelligence. This allows for problem detection and pattern prediction, providing the customer with a totally user-friendly interpretation of the data and with an indication of which O&M actions are to be taken. By precisely indicating which are the modules affected, what the problem may be and what actions are to be taken, the SunSniffer saves plant owners expensive on-site visits to diagnose the issues and enables technicians to easily and effectively repair the affected modules. This helps save up to 50% in O&M costs and improves plant performances by up to 7%. See section below “SunSniffer Technology”.
2. Sunsniffer Technology
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2.1. What is it? Integrated monitoring at module level
The SunSniffer technology by SunSniffer GmbH & Co. KG is an innovative technology designed for highly accurate monitoring at module level of the overall performances of whole PV installation, allowing for safe and consistent energy production as it increases the efficiency of the plant by up to 7% and saves up to 50% from O&M. Thanks to SunSniffer the efforts in monitoring the performance of the power plant are minimized, as this smart technology is able to detect problems and predict problem patterns from remote, which allows for tailored O&M interventions without the necessity to invest in expensive problem detection activities on site. As a result the yields from the power plant are maximized. -
2.2. What are its advantages?
SunSniffer has several advantages: -
2.2.1. Why it is needed
PV Plants do not operate as well as they could: each module is subject to natural degradation, plus faults resulting from production and external influences cause reduction in performance - often much greater than assumed.
Conventional technology provides no feedback from where the electricity is produced: namely in the module. Many errors cannot be detected by conventional diagnostic methods in the field. Further, these methods are also complex and expensive. -
2.2.2. Why it is good
Only through accurate, module-specific data collection and data analysis can data quality and depth of information be obtained that goes beyond mere error detection: where and what the problem is becomes clear. This provides you with 100% transparency on the installation.
This allows precise recommendations for action and provides an easy-to-understand display, also for non-technical personnel. Repair and maintenance costs can be accurately assessed, weighed and calculated
The simple yet ingenious technical system not only uses the existing wiring and thus offers the highest efficiency and safety, but is also extremely robust and low-priced. -
2.2.3. What is the advantage of module monitoring systems with respect to inverter and string monitoring systems?
With SunSniffer you do not have to drive into the field to check for the problem. 90% of the cases can be analyzed in remote. The repair job is defined without local diagnostics. That saves a lot of time and money. -
2.3. What is its structure
The SunSniffer system consists of different components, all especially robust and designed for an easy „plug-and-play“ integration: SunSniffer Sensor, SunSniffer String Reader, SunSniffer Gateway, and SunSniffer Webportal. -
2.3.1. SunSniffer Sensor
A small chip directly integrated by SunSniffer GmbH & Co. KG in the junction box of the solar modules. The sensor measures voltage and temperature in relation to the serial number of the solar module and transmits them to the String Reader through the Powerline Technology – the transmission runs over the existing DC, saving the deployment of further communication cabling. The measurements takes place every 30 seconds with a precision of +/- 1 %. -
2.3.2. SunSniffer String Reader
The String Reader collects the data coming from the sensors within a string of modules and measure the current as well as the voltage. The data are then sent to the Gateway via Modbus (RS 485). -
2.3.3. SunSniffer Gateway
The SunSniffer Gateway collects all data from the field: data from the StringReaders, inverters, irradiation and other environmental sensors, and transmits them to the WebPortal via internet. -
2.3.4. SunSniffer Webportal
The Webportal analyzes and edits the data. The SunSniffer Webportal does not only detect individual performance variations but can also analyse patterns (e.g., shading of a module) by using intelligent data analysis. In case of damage of the module the system informs the plant maintainers via email or SMS. Through a visualization function it is possible to see represented the whole solar installation as it was planned and built. Thanks to the module serial number, which is registered in the sensor chip, it is possible to identify univocally the module. -
2.4. Further characteristics
Sensor and StringReader communicate over the normal solar cabling using a specifically developed transmission technology (PLC, Powerline Communication). An additional installation of communication cables is therefore not necessary. -
2.5. Reliability and Plug & Play
No extra cabling thanks to Powerline-Technology (PLC).
Sensor and StringReader communicate over the normal solar cabling using a specifically developed transmission technology. An additional installation of communication cables is therefore not necessary.
3. Technical FAQ
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3.1. What is the output information?
The following information can be subsumed on the basis of the data provided by the sensors, elaborated by the system: -
3.1.1. Power Output measured
From modul, string and inverter. Plus information if there is a difference from simulation. Exact localization of the problem and report whith a suggestion which modules needs to be replaced or serviced. This is communicated to an App for field use. -
3.1.2. Contamination Indicator
The simulation software enables the irradiation sensor to calculate a set value, which is then matched with the actual current, indicating the degree of pollution of the solar modules. -
3.1.3. Instant PID Recognition
Permanent quick check: „PID yes / no“; PID is detected based on the specific PID voltage pattern of the individual solar modules. -
3.1.4. Cell Crack Detection
The SunSniffer recognizes voltage reduction patterns generated by microcracks. -
3.1.5. Shade Calculator
The SunSniffer recognizes different voltage reduction patterns which are typical of different shading types (systemic and temporary). -
3.1.6. Diode Diagnosis
The SunSniffer is capable of detecting potentially defective diodes thanks to voltage measurements. -
3.1.7. Degradation Indicator
The SunSniffer monitors the strings with a simulation engine and an irradiation sensor, calculating module degradation. -
3.1.8. Module Temperature Measurement
Temperature is an important factor influencing the performance of the whole plant. The SunSniffer measures the temperature of the modules individually, making clear what is the impact of different factors (such as wind) on specific parts of the plant. -
3.1.9. PV System Performance Indicator
The SunSniffer is capable of carrying out a full comparison of different PV systems. -
3.2. In case of faulty diode (e.g. short circuit), how does SunSniffer detect this?
Diode failures can be easily detected by our analysis engine via loss of voltage. -
3.3. In case of hot spot (bad cell), can you please tell me which is the result? Less current, less module voltage, higher laminate temperature?
In case of hotspots, we see power losses and that is what we measure, per module with an accuracy of 1%. -
3.4. In case of bird droppings?
Depending on the amount of bird droppings. This can range from lessened current up to voltage loss due to hotspots. -
3.5. In case of broken cells? Less voltage, less current (depending on the broken area)?
Broken cells can lead to less voltage and less current, depending on the type of defect. -
3.6. Another feature of the SunSniffer is the 'prediction' of faults. Can you provide a real case of voltage – temperature - system state current evaluation allowing SunSniffer to provide a fault prediction?
Yes, for PID for example. In a case of PID the modules at the end of the string a losing voltage. It is a slow but ongoing increase of loss. This will harm the modules. At a certain stage those modules cannot be healed anymore. -
3.7. Can you provide information about how and where the SunSniffer chip is installed in a retrofit installation?
Retrofits are plugged between the modules and the junction boxes - instead of connecting modules to each other in a row, the retrofit is plugged in between them. You can see this on the pages Retrofit Clip / Retrofit Box. -
3.8. In case of remote installations, let us consider a 1 MW PV system plant:
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3.8.1. About the remote data transmission, which is the average data flow in byte/hour?
It depends on the plant size. We need for each String-Reader 4 kb per hour and for an inverter 30 kb per hour. For a 2 MW plant this will add up to 4,5 MB per hour. We have an upload bandwith of 1,25kb per second. HSPDA has an upload speed of 8 kb. That means we can handle up to 12 MW plants with a normal HSPDA connection. -
3.8.2. Which is the periodical system status refresh rate (meaning a faulty module is detected and the error signal is sent by SunSniffer to the user)?
Measurements are taken every 30 seconds by SunSniffer sensor. Data is transferred to webportal about every 5-15 min. In scientific version of gateway, data transmission of gateway can be adjusted. -
3.8.3. Considering the remote data transmission, which is the phone company subscription that may be signed up for? Flat rate? Or how many GB/month minimum? Is any minimum data speed required in BPS?
Depending on plant size. With less speed, data sending interval is enlarged. For 1 MW plant, ca. 150 MByte data volume should be enough. -
3.8.4. Considering that the string reader can manage up to 30 modules which is the maximum network cable interconnection distance between 2 String Readers?
Theoretical maximum is 1.2 km, however, too long distances should not be used with normal cabeling. If there is a need for long distances and interference free transmission you should use fibre optics. You just add fibre optics media converter and have no limits in length and no interference at all. -
3.9. Is every single SunSniffer chip recognized by the central system through its serial number (or serial ID) or is this happening only when I am manually recording the serial number of the related PV module?
Sensors are always recognized by their serial number, no matter if the module serial number is known or not. However, for knowing which module is affected as well as setting plant view up, mapping of module and sensor serial number is required. During production of modules with SunSniffer sensor, mapping is automatically generated.
