Photovoltaic: Quality, Safety, and Sustainability Challenges

In a June 2024 Solar Energy Special, the Economist called solar energy generation the “least obtrusive revolution imaginable.”(The Economist 2024b) According to the International Solar Energy Society, solar power is on track to generate more electricity than all the world’s nuclear power plants in 2026, its wind turbines in 2027, its dams in 2028, its gas-fired power plants in 2030, and its coal-fired ones in 2032.

At the same time, the International Energy Agency (IEA) reckons that solar power combined with batteries is now competitive with coal-fired power in India and is on track to be cheaper than gas-fired power in America in a few years (The Economist 2024a).

While renewable energy, particularly solar energy, will enable an all-electric society in the future, quality, safety and sustainability challenges still constitute barriers to developing the photovoltaics (PV) sector. However, quality infrastructure (QI), with all its different pillars, can help overcome these challenges. A study commissioned by the Physikalisch-Technische Bundesanstalt (PTB)  in 2021 identifies the various quality infrastructure services required along the PV value chain (Ferdinand et al. 2021). It determines the requirements for further developing this sector’s global QI.

The value chain of a PV power plant or a PV rooftop facility consists of various elements (see Figure 1). Each aspect can show specific quality, safety or sustainability deficiencies.

Figure 1: PV Value Chain

1. For instance, in the value chain link ‘system design and equipment selection’, quality can be compromised by the lack of reliable meteorological information, such as irradiation data. This can lead to unrealistic performance predictions and unsuitable PV system planning and design.

2. The value chain segment ‘transport, installation, and commissioning’ can suffer from safety deficiencies through installation faults, such as wrong cabling and grounding or incorrectly inserted connectors. The possible consequence is fire and health risks for installers, operators, and people in nearby buildings.

3. The value chain element ‘end-of-life, reuse and recycling’ at the end of the value chain determines the value chain’s degree of sustainability. Lacking design for recycling and insufficient recycling at the end-of-life might result in inefficient usage of rare and valuable substances, including silver, indium or tellurium and environmental pollution by used modules.

A Calidena exercise (Harmes-Liedtke 2021) with the PV value chain in Vietnam in 2024 identified quality and sustainability issues in each value chain element that need a fix to enable the PV sector to develop and compete successfully with fossil-fuel-based energy generation and other renewable energy sectors, such as wind energy. Again, this would help Vietnam comply with its global climate change obligations and commitments as a Just Energy Transition Partnership (JETP) country. 

Why do so many quality issues materialise along the PV value chain in the first place, and what can be done to address them?

In countries like Vietnam and India, the PV sectors have experienced a sudden boom in recent years, typically fuelled by high feed-in tariffs. In Vietnam, for instance, two editions of feed-in tariffs in 2019 and 2020 led to a surge of investment in rooftop solar systems and solar farms. Consequently, the total energy produced by PV systems increased by more than 16.6 GW since 2019. On the other hand, QI development is lagging behind. While the PV sector developed rapidly within a few years, there was not enough time to articulate the demand for quality assurance services, standards and technical regulations by the market actors and the authorities in charge. The faster a sector develops, the more apparent the quality infrastructure service supply lag becomes.

However, quality assurance services are required along the whole PV value chain. Looking at the three PV value chain issues related to quality, safety and sustainability as presented above, the following QI services could be developed and offered. 

1. To address quality issues in ‘system design,’ metrology services can help calibrate and trace monitoring devices for meteorological parameters such as irradiance, wind speed, temperature, humidity, or conductivity.

2. Conformity assessment services can help improve safety in ‘transport, installation, and commissioning’, e.g., by certifying PV equipment installers to ensure their competence or inspecting plants during construction and commissioning.

3. To increase sustainability in the value chain link ‘end-of-life, reuse and recycling’, developing standards for the design of reuse and recycling processes would be a first step. This could be accompanied by conformity assessment services, such as testing recovered material and certifying components’ sustainability, i.e., their carbon footprint. Metrology would complement the QI service portfolio through related calibration and traceability services.

   
   

These are a few examples of specific quality issues and possible solutions through quality assurance services and standardisation. 

Measures for holistic QI support in the PV sector

A future-oriented sector, such as renewable energy, requires holistic and comprehensive QI support that addresses today’s and tomorrow’s quality requirements. Various measures need to be taken to achieve this (Ferdinand et al. 2021), and we will take PTB’s bilateral QI support project in Vietnam as an example. 

Support the QI alongside the development of the PV sector. 

The development of the PV sector requires the systematic consideration of quality assurance. Initially, quality assurance is often ignored when the solar energy sector starts developing but later hastily corrected when the first accidents, complaints and inefficiencies in power generation occur. This could be observed in Vietnam, India and other countries.

Take a holistic approach to the development of quality infrastructure. 

QI is a system of interrelated elements that must develop in parallel as they support and reinforce each other to make the QI system work efficiently. This equally applies to sector-specific quality assurance services and normative documents. This is why PTB in Vietnam supports its local partner STAMEQ (Commission for Standards, Metrology and Quality of Vietnam) in the areas of metrology and standardisation, conformity assessment, and quality promotion in the PV sector.

Develop an appropriate policy framework. 

Policies and the regulatory framework set the boundaries in which the PV sector operates, create incentives and define sanctions, thus influencing the demand for and supply of quality assurance services for this sector. Vietnam is a case in point. Early policies regarding high feed-in tariffs have triggered the country’s solar boom while widely ignoring quality and sustainability. The latest Power Development Plan (PDP) VIII and its implementation de-prioritize the promotion of solar and wind projects, pushing their development to the time after 2030. At the same time, various regulations are discussed to safeguard the quality of (mostly imported) PV components. All of this will influence the future quality assurance offers of QI institutions.

Foster awareness and information sharing. 

Quality promotion is the non-technical element of QI and is crucial to strengthening the quality culture in a country or a sector. Raising awareness and informing relevant stakeholders about the benefits of systematically considering quality, safety, and sustainability aspects in the PV sector is therefore essential. There is a wide array of tools to promote quality awareness in the PV sector, some of which are used in the Vietnam project, such as interdisciplinary workshops, social media posts on activities and achievements and engagement in a multi-donor energy sector group.

Support exchange and cooperation between the national PV sector and quality infrastructure organisations. 

Communication and collaboration among the stakeholders of the renewable energy sector and quality infrastructure often need support and facilitation to create awareness and find agreement on quality assurance solutions. In Vietnam, cooperation between these sectors was initially rare and fragmented. Exchange and collaboration were triggered thanks to joint events, such as a Calidena workshop and the project’s involvement in the Vietnam Energy Partnership Group (VEPG).

Base quality assurance approaches on existing international procedures. 

Initiatives to introduce quality assurance in the PV sector in other countries have led to a vast collection of experiences, inspiring practices, and international standards that can be adapted to local conditions in countries like Vietnam. For instance, a standardisation study commissioned by the project compares international standards (primarily standards of the International Electrotechnical Commission – IEC ) already adopted in Vietnam with those required to support the current status of PV sector development. An expert assessment and prioritisation of the required standards informed the country’s standardisation strategy for the PV sector for the next few years. 

Participate in international forums and organisations. 

Countries like Vietnam must engage actively in international forums and organisations like the IEC to gain easier access to international approaches and start co-shaping their discussions. The PTB project supports the national standardisation body VSQI’s participation in the technical committee 82 of the IEC, which develops global standards for solar photovoltaic energy systems.

Plan the development of quality infrastructure following the national PV strategy and the stage of sector development. 

PTB has gained experience in QI projects focusing on PV systems in various countries in Asia, Africa and Latin America. Two critical lessons learned prevail: (1) the national solar energy strategy and related policies need to be considered, and their changes observed when developing the quality infrastructure for the PV sector; (2) it is essential to understand the current stage of development of the PV sector in a country. In Vietnam, the PTB project started during the design phase of the PDP VIII, which unfortunately needed two years to be approved and passed. At the same time, Vietnam became a JETP country, attracting external financial support for renewable energy projects and receiving additional obligations. 

Meanwhile, the installation of roof-top solar facilities and large-scale solar farms stagnated due to the political uncertainties related to the slow enactment of PDP VIII. Also, various Chinese PV cell and module producers opened manufacturing sites in Vietnam to avoid being subject to import duties by the US, but initially without using local testing and certification services in Vietnam. All these developments must be observed and assessed to determine what they could mean today and tomorrow to shape a QI support project and its future adjustments or extensions.

In conclusion

Developing or upgrading QI in complex sectors like the PV sector in a setting where quality assurance was widely neglected in the past must be holistic, systemic and intensely cooperative to get all relevant stakeholders on board and facilitate inter-sector communication. Renewables, including solar, are the energy sources of the future. Assuring the quality, safety and sustainability of their technical components, energy generation, distribution and usage processes, and end-of-life decisions is essential for their reliability and credibility in future. 

Sources:

Ferdinand, Niels/ TelfserKatharina/ Heider, Catrina and Balbin, Nancy. 2021. “Quality Infrastructure for Photovoltaic Systems – Assuring Safety, Quality and Sustainability in Emerging and Developing Economies.” Physikalisch-Technische Bundesanstalt (PTB).

Harmes-Liedtke, Ulrich. 2021. “Calidena – Closing Quality Gaps Jointly.” QI4D (blog). December 12, 2021.

The Economist. 2024a. “Clean Energy’s next Trillion-Dollar Business,” September 1, 2024.

———. 2024b. “Sun Machines,” June 20, 2024.