SCADA stands for Supervisory Control And Data Acquisition; it is a computer-based control system used to gather and analyse the real-time data in industries. The purpose is to monitor and control of process and equipment. First generation SCADA comprised of rugged hardware called PLCs which connected to various sensors and collected data in digital format for further processing.

A Solar PV Power Plant doesn’t need much of controlling, it is all about monitoring. Hence you do not need a complex PLC based SCADA system. There are thousands of panels, kms of cables, tons of connectors which if monitored gives information on health and performance of the PV plant.

All you need is an IOT platform. EagleSun SCADATM from Avi solar is one such simple, low cost, effective monitoring system designed specifically for Solar PV plants.

If you are using a PLC-based SCADA – Switch to Ultra low-cost IOT based EagleSun SCADA now!



For any technical queries Email- eaglesun@avisolar.comPLC SCADA VS IOT SCADA

For Solar PV Monitoring Products and O&M services  visit

India's Top PV Monitering System

Is Your PV Remote Monitoring/SCADA System Functional?

Have you invested in a best in class Solar PV SCADA and now unable to monitor your PV Plant? You are not alone! There are several Solar PV Plant owners repenting their decision on the choice of PV Monitoring system/SCADA.

At Avi Solar Energy, our Analytics & Monitoring team studied and analysed over 1GW of Solar PV plants across India. Here is the summary of our analysis:

For a Solar Plant Developer, getting the Inverter up and pumping power to the grid has been the focus when a new plant is built. SCADA is the last item in punch list, because even if it is not functional, the generation is still ON! Its only after couple of years after the plant is commissioned, when the O&M team reports issues at the site, plant owner realizes that monitoring is important to figure out the performance of the plant.

Here are some of the major issues with SCADA / Remote Monitoring systems that we have experienced in field

1.  Leased line connections not working.

Most SCADA needs a high bandwidth internet connection like leased lines, which are very expensive to maintain.

2.  Developers have not renewed the AMC with SCADA supplier

Many suppliers sold their system at low prices initially, but owners didn’t know that you need to pay a heavy premium every year.

3.   Cables connecting the SCADA systems are damaged.

Most traditional SCADA systems were interconnected using Kilometres of Fibre Optic / Copper cables, which have been damaged by unskilled labourers at the plant.

4.  No Service / Support engineers visit the plant

Many leading SCADA suppliers provide you telephonic support. But to resolve major issues you need to depute service engineers at these sites which are usually in remote areas.

5.  SCADA is limited to control room only.

Many plants have a monitoring system at the control room, which means you are at the mercy of site engineer. Data accuracy and relevance could be at stake if the plant can’t be monitored remotely.

6.  No String Level Monitoring.

Data collection is limited to Inverter monitoring only.

String level faults cannot be detected.

The good news is that, there are retrofit solutions available which can replenish your existing SCADA and bring the plant data to your remote monitoring centre. IoT being the buzz word today, there are several options to get the data from your plant to the cloud in a cost-effective manner. There are several IoT platforms which can monitor data from PV plants. EagleSun SCADA™ is one such platform exclusively developed for Solar PV Plants.

As the PV plant gets older, one needs to watch for performance degradations, losses due to aging of plant BOS like connectors, cables and terminations. Your SCADA needs to be operational and you need to have the plant data. It is strongly recommended that you monitor all the equipment, mainly the Inverter, Weather Station, String Combiner Box, Transformers, VCB and Energy Meters. If cost concerns exist for string-level monitoring, Zonal level monitoring solution can be considered.

The history of your plant will not only give insight into the performance parameters, it can also help you a great deal in forecasting & scheduling.

EagleSun SCADA™ is one of the cost-effective solution to retrofit your remote monitoring system. Service support is equally important. Avi Solar team being the leading provider of O&M services for Solar PV assets, with their professional team of engineers and technicians can provide local support for the EagleSun SCADA™ across India.



Snail Trails on Solar Panels – an aesthetic issue or a performance limiter?

Snail Trails on Solar Panels– an aesthetic issue or a performance limiter?

As Solar Plants age, Developers must reckon many problems. Modules do degrade over time and may underperform. Microcracks may develop as modules are exposed to the elements all through their life time. Some modules may inherently have had micro cracks from the time it was shipped and can extend over larger cross-sections during operations. Over & above thermal cycling can affect metal contacts, solder interconnections & causes thermal stresses in the module. This can have serious consequences and may result in catastrophic failure in the long term.

Since 2012 a phenomenon has been observed across many Solar plants, of small dark brownish lines or partial discoloration being caused on PV modules. These were termed “snail trails” and research started on its occurrence and the impact it can have on power generation.

After studying patterns across many plants, it was broadly concluded that mere existence of snail trails by itself does not affect power generation. However, snail trails seen where micro cracks run across cells may affect power generation. Even this must be assessed to be sure.

What are snail Trails: 

Snail trails are discolouration of the panel, which usually builds up over couple of years of power production on the field. Moisture can enter through the back sheet and diffuse to the cell surface. Here the silver from the grid contact fingers may get dissolved and the silver ion migration to the EVA (Ethyl Vinyl Acetate) foil encapsulation can set in the snail trail formation – mainly Silver nanoparticles showing a typical brownish colour.

It has been ascertained that this discolouration happens due to the formation of silver acetate, that is synthesized by silver carbonate (Ag2CO3) originating from the reaction of Ag ions and carbon dioxide and acetic acid that originates from the degradation of the EVA encapsulation. The effect of this reaction is that it can reach the front of the panel from the back and causes a chemical breakdown on the front of the panel of the grid fingers. This becomes visible as snail trails and was possibly thought to bring in a reduction in the panel’s performance as it can cut irradiance if these trails run across the cell. Though it is not true it is surely an indicator for cracks within the cells. The snail trails are almost always located at cell edges or along micro cracks that can run across the cells in the panel and these are ones that can possibly lower power production. So, it is more of chance that the cracks are deep enough that may result in more stresses building up and thereby a deterioration in performance by creating potential hot spots.

In view of the perception that snail trail affected modules can have adverse impact on generation, Developers are a worried lot that the solar plant should not affect their Return on Investment (RoI) and reduce the life of the modules.


It is better to ascertain the impact by conducting tests on samples of snail trail affected modules. 

Various tests are possible such as

  • Thermal Imaging
  • Electroluminescence
  • I-V tests                        
  • Raman Spectroscopy.

Figure 1: Snail trail affected module

Figure 2: Thermal Imaging of Snail Trails on Module

To assess performance differences between snail trail affected and unaffected modules the string currents were measured during peak generation time. Data is shown for two sample sets.

No conclusion could be drawn about underperformance of snail trail affected modules.  Observation was that the values of current and voltage continued to be in the same range for both sets of modules

The technical team recommended that one of the best methods to assess the impact of Snail trail affected modules is to carry out Electroluminescence (EL) tests to gauge the structure and depth of the microcracks within the module from the EL images alongside I-V characteristics of the modules. Some samples were taken for EL tests/I-V tests. The Fill Factor (FF) of one of the modules recorded a drop of 6% against data sheet specifications. Considering the age of the plant to be 4 years, a 6% drop in FF in one of the modules translates to an annual average deterioration of 1.5%, slightly above usual thresholds of degradation. This could possibly relate to the microcracks in the snail trail module affecting performance. The values of the Series resistance of the cell showed up higher for such affected cells than other unaffected modules.

Figure 3: EL image of Module with micro-cracks

A clear picture will emerge after performing Electroluminescence tests and I-V characteristics tests. The intensity of the cracks, if any, can easily be seen and the Fill Factor data from the I-V tests will be an indicator of any performance dip or quality problems in the module. If the results match the manufacturer specifications or indicate minor problems, then it can be concluded that the performance aspects are intact, otherwise these affected modules are the ones to observe for deterioration in future.


Another way to understand the effects of snail trail affected modules is to analyze the monthly plant generation recorded during the previous year and compare it during the same month in the present year. If the generation difference is <0.8-1% a year later under non-break down conditions and normalized to insolation levels, it is well within limits of degradation – very usual of plants ageing and the performance ratios dipping year on year. Otherwise, it can be gathered that the module degradation has set in for the affected modules.

Replenish your Non-functional Solar PV Plant SCADA

Replenish your Non-functional Solar PV Plant SCADA 

Have you Invested in a world-class Solar PV SCADA and now unable to monitor your PV Plant?

You are not alone! There are several Solar PV Plant owners repenting their decision on the choice of SCADA supplier.

Avi Solar Energy Pvt Ltd., with their experience of managing over 1 GW of Solar PV plants across India has analyzed and understood why most of the SCADA systems are not functional.

Here are top 4 reasons:

  1. Leased line connections not working.
    • Most SCADA needs a high bandwidth internet connection like leased lines, which are very expensive to renew.
  2. Developers have not renewed the AMC with SCADA supplier
    • Many suppliers sold their system at low prices initially, but owners didn’t know that you need to pay a heavy premium every year.
  3. The cables connecting the SCADA systems have damaged.
    • Most traditional SCADA systems were interconnected using KMs of Fiber Optic / Copper cables, which have been damaged by unskilled labours at the plant.
  4. No Service / Support engineers visit the plant
    • Many leading SCADA suppliers provide you telephonic support. But to resolve major issues you need to depute service engineers at these sites which are usually in remote areas.

Don’t we have a solution? can’t we restore the Remote monitoring SCADA?

You can!

Switch to EagleSun SCADATM, which is a wireless remote monitoring system designed & developed by Technical Solutions Group (TSG) of Avi Solar. These developers mostly coming from the IT industry who have developed products for multinationals, gather knowledge from Avi Solar’s O&M engineers who have REAL field experience on all different PV technologies. They understand what works & what does not at PV plants.


EagleSun SCADA is a low cost solution , can inter operate with your existing SCADA with no/minimal changes to your existing SCADA system

Call us today on +91 70229 49911 / 99806 98001 or email for more details on how you can get your plant data on your smartphone or PC.

For any technical queries write to 

Solar PV Forecasting & Scheduling – Integrated with EagleSun SCADA

Forecasting and Scheduling (F&S) regulations for renewable energy generators, specifically for Solar PV plant owners has been communicated by SLDC and the industry has started gearing up for its impact! The effective dates for DSM penalty are in place for many states.

The requirement is to submit  day-ahead power generation  which can be done using different ways shown below:

  1. Energy generators (IPPs) can submit the F&S directly to SLDC
  2. Third party (FSS) on behalf of Energy generators (IPPs) can submit the F&S directly to SLDC
  3. QCA can submit the aggregated F&S to SLDC
  4. Aggregator (Agg) can submit the aggregated F&S to SLDC

Avisolar Energy is also one of the QCA and is already submitting F&S in the states of Andhra Pradesh (AP), Telengana (TS) and Karnataka. With our experience managing over 1GW of Solar PV plants, the Technical Solutions Group (TSG) has developed a robust forecasting algorithm which generates week ahead and day ahead generation.

This easy to use forecasting tool can be integrated with Avisolar’s wireless remote monitoring system -EagleSun SCADA.






EagleSun SCADA gets real time data from  Inverter. The key parameter needed for F&S is AC Power . This data is continuously monitored, compared with the forecasted power and the deviation is calculated instantaneously.

For more details & a free demo of the F&S tool pl write to

Defining new Trends in Solar PV Plant Monitoring– Avi Solar launches – EagleSun SCADA


The world is moving towards utilization of renewable energy and with installations of numerous solar PV Power Plants, it has become a challenge for the plant owners to manage their assets precisely. Solar Power plants are spread across vast landscapes in remote areas and deploying technical personnels to monitor the plant is not a viable option anymore. Avi Solar has indigenously developed advanced SCADA system to manage and monitor Solar PV plants. SCADA introduced by Avi Solar is tested and applauded by numerous Solar Plant owners for its accuracy and intuitive design.

Real time monitoring of power plant with an efficient SCADA system can save a fortune for plant owners. The losses due to one underperforming PV string may seem very small, but if unattended this can have a multiplier effect and can have a large negative impact on yearly profit.

A Typical EagleSun™ SCADA Interface for Real Time Monitoring

EagleSun SCADA system comprises of RF based Communication hardware and cloud based software which needs a simple 2G/3G datacard at the site to monitor the plant. The hardware interfaces with all major equipment in field like string combiner box, Inverters, Weather station, MFM, VCB panel and all other sensors. A simple user friendly graphical interface allows plant owners to see their generation data remotely on their smartphones or PCs.

Robust Hardware (SCBs and RF Communication)

An engineer can monitor breakdowns, manage alerts and generate reports for in-depth performance analysis. For owners of multiple plants, Avi Solar can provide customized dashboard to monitor and compare multiple plants on single login. Since EagleSun SCADA is developed inhouse, it is very cost effective and is also backed up by Avi Solar’s best in class service guarantee.

Avi Solar Energy Pvt Ltd is India’s leading independent O&M service provider for solar PV plants. With the field experience from over 700MWp assets, company has started developing SCADA and other monitoring products that are customized for PV plants. The development team comprises of highly accomplished & passionate product designers who have worked in MNCs, and released several global products. These products were deployed & tested in all projects for which the company performed EPC. The flagship product EagleSun SCADA is now available for power plant owners across the country.
With over 10GWp of solar PV plants commissioned in India, several SCADA systems are either non-functional or the data is unavailable remotely or the owners have not renewed the hefty annual license fee! Avi Solar is not only providing solutions to new plants but also has started replacing some of the existing SCADA systems with EagleSun SCADA which needs simple 2G/3G data connectivity at site.

— Sayed Sahid- Marcom Executive