An Interview with Mr. Asier Ukar Naberan, PI Photovoltaik-Institut Berlin AG
1. Rapid expansion in PV manufacturing capacities has led to dramatic drop in PV module prices. How amidst this mass manufacturing, the highest quality is maintained, particularly considering that the modules come with 25 year power warrantee and how your organization offering QA services is helping the industry achieve and maintain high quality?
We are in the business of PV module quality assurance (QA) since 2006, with three accredited laboratories running in Germany, China and since 2020 also in Ahmedabad, Gujarat with our partner Mitsui Chemicals India (MCIND). The high variety of technologies and module types nowadays require a tightened quality control program in order to detect and mitigate potential risks that may threaten the planned revenues once the PV plant is in operation. This is particularly relevant in high competitive markets like India with low margins and also harsh environmental conditions that make testing beyond basic IEC standards even more relevant. Banks and lenders know that as well and this is why they are pushing the Solar Power Developers more and more to implement module QA programs as part of the loan agreements. The Indian solar sector will play a decisive role in the future and this is why we have decided to build an infrastructure in India with a team of engineers and researchers offering laboratory, engineering and consultancy services.
2. PV, inverter and other connected technologies are rapidly changing and new technologies like AI, ML etc. are getting integrated even more rapidly. How amidst all these swift changes the quality standards whose development takes far longer time, are evolving.
Such innovations are mainly driven to optimize the O&M services by means of an increase of automatization in the data evaluation, reduction of manpower and optimization of the preventive and corrective maintenance tasks. This can be achieved with big data and AI that introduce predictive maintenance algorithms that help focusing only on those tasks which are really relevant at that moment, making the whole O&M strategy more efficient both technically and economically. This approach is certainly compatible with a previous QA program on inverters, modules and mounting structures. We actually believe that the stricter the QA program is during the manufacturing phase, the easier and cheaper will be the O&M services.
3. You have carried out detailed evaluation of underperforming rooftop solar systems in some major Indian cities. Could you please sum up the common and major causes of underperformance and how successfully the mechanisms you recommended for their avoidance have been implemented since then.
PI Berlin was contracted by GIZ as part of the project “Indo-German Solar Energy Partnership – Photovoltaic Rooftop Systems (IGSP-PVRT)” and was financed by the German Federal Ministry for Economic Cooperation and Development and implemented by GIZ in partnership with the Ministry of New and Renewable Energy (MNRE). The goal was to (i) identify the causes of underperformance in 40 pre-selected rooftop PV plants located in Delhi, Pune, Andaman and Nicobar Islands and Surat, (ii) quantify those in terms of contribution to loss in generation and (iii) propose cost-optimal solutions to address the quality issues. The results of the evaluation showed that the low performance of the inspected rooftop PV plants was caused by a mix of disregarded design constraints, installation failures and product defects. Specifically, the main detected issues we found were: Potential Induced Degradation (PID), heavy soiling, shading and module damage during transport and installation. According to the observations and measurements conducted by PI Berlin during the site assessments, these key findings contributed individually to losses at the system level between 6% and 30%. The results of this study (“Moving from kW to kWh”) were made public and can be found on the website http://www.kwtokwh.in/. A second goal was to identify potential benefits for O&M contractors and developers in existing and future projects based on the findings. In this sense, PI Berlin suggested 5 revamping and repowering measures which, depending on the state of each PV plant, may lead to a performance boost between 5% and 50%. PI Berlin proposed 10 affordable prevention mechanisms for new projects that included technical and commercial recommendations to ensure their long term viability. These are currently being proved by MNRE and will be implemented soon.Due to the good feedback received by the involved stakeholders, a second phase has been launched for 2021 with further 80 rooftop PV plants to be analized. We will evaluate these with our partner Mitsui Chemicals India (MCIND).
4. Many times it is contended that the PV standards are more applicable to the temperate and colder geographies than those that have hot and humid climate for most part of the year and that standards more applicable to specific geographies have to be developed and adopted. What is your stand on this contention and what are your suggestions?
First of all, we must take into account that in India we have four or five predominant types of climates, unlike other PV active areas such as the Atacama Desert (Chile), MENA or the Southeast Asian region – which have a much more homogeneous climate distribution. It is important to note that some of these climates, such as those in Chennai or Jodhpur, are especially aggressive. Considering that the IEC is not capable of guaranteeing a durability of 25-30 years in temperate climates, with less reason it is for India due to its particularly aggressive climate affecting almost all the components of a PV plant. That said, the basic IEC or BIS standards are not enough to ensure long term reliability. New testing procedures tailor made to the needs of the Indian solar sector must be applied focusing on extended duration and combination of stressing factors. Our laboratory in Ahmedabad can conduct these specialized reliability tests in order to provide an added value to the sector. This is a great challenge when establishing standards at both macro-scale (BSI) and microscale, for example in specific tenders, since a module installed in Kerala will face a combination of environmental stressing factors different from the one for example in the Kutch desert in Gujarat.
5. Incidences of extreme weather are becoming frequent with wind speeds, temperature, flooding etc. rising alarmingly. This has led to enormous destruction of assets and huge pile up of highly space occupying debris. How adequate are the current standards, design and installation practices to effectively prevent asset losses and what are your recommendations?
In this regard and acting on behalf of the German metrology institute Physikalisch-Technische Bundesanstalt (PTB), PI Berlin has conducted two actions. On the one hand reviewing the latest versions of both the roof-top and utility-scale tenders released by SECI in the past 4 years, with the goal of reinforcing the quality requirements and reducing significantly the amount of quality issues during the construction and operation phase. These tenders are key as they determine right from the beginning the future quality of the PV projects with regards to the design, construction and O&M. Secondly, and building up on the reinforcement of the SECI tenders, a “Construction Monitoring Tool” and “TDD Tool for Operating Assets” was created for IREDA and other Indian financing institutions to support the evaluation of solar PV assets during the construction stage. This instrument is particularly important because it provides a final risk assessment, based on a rating classification, through a scoring and weighting system. Using this tool, banks and financing institutions will be able to better adjust their financing conditions, based on the assigned rating and identified risks. We recommend following the guidelines embedded in these tools since they include not only existing Indian standards, but also new requirements that will help detecting, quantifying and mitigating risks at early stages.
6. There has been rising concern in India that in the race towards winning large projects, tariffs that are unsustainable are being quoted and that may lead to compromises in the quality of design, components, installation practices etc. Having visited plants and evaluated them, please let us know your overall perspective on this and your recommendations to ensure quality in these highly competitive environment.
Considering the benefits that quality assurance brings in terms of prevention of unintended financial consequences, OPEX savings and increase of bankability, is the investment in proper quality assurance really too expensive? This initial investment in quality control contributes to properly assess the real OPEX during operation and avoid an inflated CAPEX at the expense of OPEX in order to obtain better financing conditions. Transparency in the financial modelling is only possible with a solid intelligence gained during product selection and manufacturing control. With increasing demand, the momentum gained in the Indian PV market requires laying the foundations for a future that ensures investor confidence, reliable energy generation and, especially, the reputation of the Indian PV market worldwide.