Standards Development

Scope

This document specifies requirements, testing methods, and performance criteria for photovoltaic (PV) modules intended for use on floating solar platforms. It aims to ensure the reliability and durability of PV modules when deployed in environments associated with bodies of water (e.g., lakes, reservoirs, near-shore, and offshore settings). The standard covers mechanical, electrical, and environmental factors that affect the operation of PV modules on floating systems.

This document does not intend to replace the qualification and type approval IEC 61215 series but aims at integrating it with more specific tests for the water environment. It is intended to apply to all terrestrial flat plate module materials such as crystalline silicon module types as well as thin-film modules. It does not apply to modules used with concentrated sunlight although it may be utilized for low concentrator modules (1 to 3 suns). For low concentration modules, all tests are performed using the irradiance, current, voltage and power levels expected at the design concentration.

The objective of this test sequence is to determine the electrical characteristics of the module and to show, as far as possible within reasonable constraints of cost and time, that the module is capable of withstanding prolonged exposure in the water environment. 

Mechanical stress tests are designed to reproduce the levels of stress caused by

: • wind load (testing for resilience to wind pressure and suction on floating platforms in open water);

• wave load (evaluating PV module tolerance to wave-induced torsion, vibrations, impact and other mechanical stresses). Climatic stress tests are designed to reproduce the levels of stress caused by:

• high UV radiation (testing resistance to increased UV exposure, also due to reflection from water surfaces);

• humidity and condensation (evaluating the impact of high humidity and frequent condensation on electrical performance);

• thermal shock (accounting for water-induced temperature shock, with potential rapid change of the module operating temperature to the water temperature caused by the contact with water);

• water immersion (ensuring modules have enhanced insulation and water-proofing to prevent damage from constant exposure to water and humidity and potential extended periods of time of water immersion); Biological and chemical stress tests are designed to reproduce the levels of stress caused by:

• salt mist corrosion (for near-shore and offshore systems, testing for salt spray and mist effects on modules);

• biofouling resistance (evaluating whether algae, barnacles, or other biological organisms that thrive on water surfaces affect module performance);

• ammonia corrosion (evaluating the ability of PV modules to withstand exposure to ammonia, which is common in water bodies near agricultural or industrial zones and can accelerate the degradation of materials and electrical components).

Accelerated test conditions are empirically based on those necessary to reproduce selected observed field failures and are applied equally across module types. Acceleration factors may vary with product design and thus not all degradation mechanisms may manifest. Further general information on accelerated test methods including definitions of terms may be found in IEC 62506. Some long-term degradation mechanisms can only reasonably be detected via component testing, due to a long period of time required to produce the failure, as well as the necessity of stress conditions that are expensive to produce over large areas. Further general information on extended stress-testing may be found in IEC TS 63209-1

Purpose

The proposal seeks to address the strategic goals 3, 4, 5 and 6 of IEC Strategic Plan under the themes “Enabling a digital and all-electric society” and “Fostering a Sustainable World”, in particular for what concerns the deployment of renewable energy technologies like solar that are crucial to reducing CO2 emissions in the electricity sector. A TS for the qualification and type approval of floating photovoltaic (FPV) solar modules can enhance business certainty by standardizing performance metrics, mitigate technological risks by ensuring module durability in aquatic environments, address societal needs by supporting renewable energy adoption, and promote environmental sustainability by reducing land use and improving water management in solar power generation.

FPV systems offer societal benefits by potentially increasing access to renewable energy, reducing land competition for agriculture and housing, fostering the combination of electricity generation, with aquaculture and fish farming, conserving water through reduced evaporation, and supporting energy security in densely populated or water-scarce regions, contributing to sustainable development and climate change mitigation.

The global market potential for FPV solar systems is growing rapidly, often due to the scarcity of land in densely populated areas, the need for renewable energy in remote areas and non-urban areas, and the benefits of the cooling effects of water-based solar generation. Notwithstanding the impressive growth that is documented by the global metrics below, an IEC standard for qualification and type approval of solar modules to be installed in FPV system is still missing.

It is known and proven that the water environment presents unique environmental and mechanical stresses that differ significantly from land-based solar installations: these can impact the performance, durability, and reliability of solar modules. Some key factors and stresses that floating solar modules face compared to conventional land installations are: humidity and water exposure; wave motion and mechanical stresses; thermal shocks; biological growth and fouling; saltwater corrosion (for marine installations); other chemical stresses (for installations in industrial areas).

Relevant global metrics:

• Installed capacity growth: The total installed capacity of floating PV systems was around 6 GW by in 2023. The global floating solar market is projected to grow at a compound annual growth rate (CAGR) of about 34% from 2024 to 2030. By 2030, it is estimated that floating PV capacity could exceed 40 GW globally.

• Potential surface areas: With reference only to freshwater bodies, global reservoirs and artificial water bodies cover approximately 400,000 km². If just 1% of this area were utilized for floating solar, it could generate around 400 GW of solar power, which can be estimated to power over 100 million households.

• Energy generation gains: FPV systems benefit from water’s cooling effect, which can increase energy efficiency by up to 10 -15% compared to land-based solar farms, depending on the region and installation design.

• Market potential by region:

o Asia-Pacific: Dominating the FPV market, particularly China, Japan, South Korea, and India. China alone had over 1.3 GW of installed capacity by 2022. The Asia-Pacific region accounts for more than 60% of global FPV installations.

o Europe: The EU's Green Deal and the energy transition in regions like the Netherlands and the UK are driving growth. The European market could add 4-5 GW by 2030.

o North America: Increasing interest, especially in the US, where FPV could help combat drought and conserve water resources.

• Environmental impact: FPV installations can reduce water evaporation in reservoirs by 30-50%, contributing to more efficient water management in water-scarce regions. Furthermore, it can be estimated that a significant FPV deployment could save over 200 million tons of CO2 emissions per year if globally scaled to its potential.

• Market value: The global floating solar market was valued at $1.9 billion in 2022 and is expected to surpass $10 billion by 2030 as technology matures and more large-scale installations occur.

Guidelines for the qualification of solar modules towards the specific stresses of FPV systems have the potential to remove trade barriers and improve international market access, fostering collaboration in global supply chains, and promoting the harmonization of regulations. This would enable wider adoption of renewable energy solutions, stimulate cross-border investments, and facilitate the exchange of technical expertise, creating new opportunities in emerging and developed markets alike.

This TS is intended to be used as a guidance for reliability testing, but is planned to be further developed in future editions to support conformity assessment of solar PV panels for use in FPV systems.

This document is a TS and is not a horizontal standard