Testing your solar panels

An in-depth analysis on the importance of T&M instruments in solar power sector.

I ndia is being seen as a major solar hub as it has huge potential in the solar segment. Presently India targets 100 GW solar by 2022 but for that it needs to ramp up the capacity. To achieve 100 GW solar it is necessary that the solar panels, solar cells, work efficiently and without any defects and to assure a smooth working systems testing and measurement (T&M) instruments plays important role in the solar power sector.

Importance of T&M instruments in solar power sector
Right from the existence of power sector, there has been a need for T&M instruments, as they help in maintaining the healthiness of grid assets. With solar energy becoming a primary focus in power sector, maintaining the grid becomes even more challenging, since solar produces power in DC which has to be converted to AC to synchronise with the Grid, says Sanjay Kulkarni, Chairman, SCOPE. He explains, “Earlier, in the traditional non-renewable system, only AC test instruments were needed. However, now both DC and AC testing instruments are required. Having said that, demand for instruments required for CB testing, transformer testing, LA testing continues as earlier. Some testing instruments, such as vibration analyser, which were once considered critical for traditional power generators may now lose its relevance. On the other hand, new instruments would be needed in solar sector, which although may not necessarily be testing instruments, albeit play a critical role in maintaining the grid.”

Engineers are working towards making a grid smarter and T&M instruments would help them to make grid even more smarter believes Avichal Kulshrestha, Staff Technical Marketing Engineer at National Instruments. He says, “Engineers and scientists worldwide are collaborating to create a smarter grid to improve grid integration of renewable energy sources, implement automated analytics, advance situation awareness, and improve overall energy efficiency. These applications pan across sources like wind, air and solar. It is highly crucial that all these elements provide power output in synchronisation with the grid.”

T&M instruments and solutions can be used as design tools, test systems, and embedded deployment platforms giving these engineers the ability to rapidly explore new approaches, streamline discovery and production, and deploy their innovations in ruggedised measurement systems. These systems can be used for two primary reasons that are power quality analysis and condition monitoring. Specifically, for solar based sources other aspects such as PV panel testing, asset monitoring, power metering and efficiency testing are other major areas where T&M equipment are needed. Additionally, certain T&M vendors such as National Instruments also provide tools for developing controllers and converters for solar energy conversion along with the test and measurement equipment as well.”

Indian government’s drive in promoting renewable energy is indeed commendable since it sustains our mother earth and ensures greener environment. “SCOPE too has a humble contribution in this by ensuring high-quality products that comply with stringent CE standards,” adds Kulkarni.

T&M instruments have a very important role to play in solar industry as it ensures right quality of products to come in the market. “Equipment like solar simulators play important role, starting from research stage up to the production of final products. The conformity to specified test standards is also ascertained. During solar installation testing equipment helps in ascertaining continuity, insulation resistance, open circuit voltage, short circuit current etc. Thus, making successful installation and maximising return on investments. Even basic equipment like irradiation meters helps in determining best installation angles. Measurement equipment like Data Loggers, Pyranometers are very much essential in determining the solar plant performance, weather conditions impacting performance and also fault detection,” says Sushil Kumar Sarawgi, Director, KOR Energy (India) Pvt. Ltd.

It goes without saying that testing and maintenance are one of the important and essential activities for solar power generating system. It ensures safe and successful commissioning of the system and also ensures a long life with a generation that is at par with the capacity of the system. To function well, a system needs a thorough, both off-site and on-site, testing of individual equipment as well as the complete integrated system. According to Gyan Prakash Tiwari, Co-founder, MYSUN, “Even one faulty component can bring the whole system performance crashing down.” He observes, “Testing is not only important for successful installation and commissioning but also to run an installed system efficiently and safely.”

Some of the tests that are commonly performed are:
• Polarity of all DC cables
• Hot spot test.
• PV string open circuit voltage test
• PV string short circuit current test
• Insulation resistance test of cables
• Earth resistance test
• Operational test – PV string current.
• Functional test
• Performance ratio test.

In the recent past, we have witnessed a major shift and increased dependency on non-conventional sources of energy. It is very evident and certain that sure there will be substantial growth in solar power sector as well. “Because of this, regular T&M in this sector looks indispensable and is necessary to ensure proper functioning of the set up without any breakdown,” explains Parag Yelegaonkar, Business Development Manager, Testo India Pvt Ltd.

He adds, “Since the solar sector constitutes a major share in the power generation and distribution, the T&M instruments are very vital to assure safety against possible fire threats, circuit breakage or any other damages.”

Testo recently launched an entire range of new Thermal Imagers that can identify the defects in solar cells at module level for the possible cracks, voids, open and short circuit of the tracks in solar cell joining/junctions. These solar thermography inspections can avoid loss of entire array and string efficiency. “Testo Electrical Measurement Instruments are excellent instruments to inspect the electrical components and circuit failure threats,” claims Yelegaonkar.

Opportunities galore
Solar sector has opened up many opportunities. Here is how T&M players describe about their opportunities.

Rise in small and large scale solar power sector is focus area.
India as a country is investing heavily in renewable energy and non-exhaustible sources of energy. “There is a heavy push from government to support initiatives on smart grid, micro grids and alternate sources such a solar. There are subsidies available for consumers planning to switch to such sources for fulfilling their power consumption requirements. This has given rise to demand of small scale to large scale solar power equipment. Given that this is a focus area for companies working in the solar power sector, it is very important that T&M companies innovate and come up with solutions for these companies,” observes Kulshrestha. “NI being a leader in test and measurement equipment provider is ensuring a focus on R&D in this area as well. NI is one of the several industrial leaders who are working on bringing up the new standard for condition monitoring which is Time-sensitive networking. Also, NI has come up with products for Indian companies to make easier for them to run tests and do monitoring on their solar and other renewable power solutions,” claims Kulshrestha.

Development in industrial and infrastructural areas has increase the need for T&M
While sharing views on opportunities in India Yelegaonkar says, “At the current scenario when we are witnessing a great development prospect in all the industrial areas accompanied by the infrastructural renaissance and growing power and energy concerns, the needs for T&M instruments has increased big time. Now when the government has also become so focused on the upcoming concepts like smart cities, green technology and renewable energy conservation, the T&M industry is sure to see a great future ahead as the applications are going to increase and so are the solutions required. Testo also hopes to offer many technologically advanced products in the coming era of opportunities.”

Eyeing products conforming to all International Standards
Sarawgi informs, “In India, there is a huge market potential for T&M equipment as we are also eyeing for world-class products conforming to all international standards. Most of the Indian manufacturers are now confirming to the international test certifications, hence there will be a great demand for T&M equipment. There is a great emphasis also on plant performance and customers and agencies are also insisting on installation of data sloggers, sensors, pyranometers so that optimal plant performance can be achieved and maintained.”

Sharing views on the opportunities, Tiwari says, “As gradually manufacturing of solar components, be it the modules, inverters or other components look to be scaling up in India, the opportunity for testing and maintenance is huge. Since the market is developing and there is a growing demand, even though gradual, the systems manufactured here need to be thoroughly tested before they can be installed. Not to forget, that a well tested system, would ensure a good output and bring a level of confidence among the consumers too leading to a solid word of mouth. You do not want to be giving out a half tested or worse, no tested system to the customer, which ends up failing on him. This scenario will have not just give the said brand a bad name but also gives the whole industry a bad name. Inline to the same, the MNRE too has recently issued an order clearly specifying the quality control that should be followed for individual components of the solar system. At the infancy that solar is today, we need to take our steps cautiously and ensure that the customer is always satisfied so that the growth of solar overall can continue to spur on.”

Demand for O&M of solar panels also increased
Sanjay Kulkarni of SCOPE mentioned that due to boost in solar power system, a sea of opportunities has opened up. He adds, “Other than the T&M instruments, demand for O&M of solar panels has also increased. Volt VAR compensation in case of solar power is of prime importance and SCOPE has low-cost yet most effective solutions for this and we see this as biggest opportunity in the near future.”

Other than renewable, the power ministry has also focused on strengthening the existing grids under PSDF. The fund is made available to the state utilities to enhance their grids to ensure that latest testing instruments are available and this creates an opportunity for us.

Over the years, testing has become more and more sophisticated, and this too has created an opportunity. Over the course of time, SCOPE has introduced various products which are sophisticated, like their Transformer Turns Ratio meter – TTRM 302 with touch screen and vector group detection facility, Wireless Leakage Current Analyser – SA 30i+ for testing LA’s are few of the examples.