Roadmap 3
Recycle and Recover
Rationale for support
Current PV modules on the market are not designed for circularity (meaning easy to disassemble, repair, refurbish, and recycle). They cannot be “re-opened” and the only way for recycling is through destructive processes such as shredding. The irreversible design severely limits repair/ refurbish potentials, as well as the recovery of valuable materials.
There are multiple research initiatives in PV eco-design (such as CABRISS and EcoSolar). But despite the advance- ments in technological research, there is currently a clear lack of business incentives for manufacturers to implement design-for-circularity.
Following the material efficiency hierarchy, resources should be kept in productive use as long as possible and at the highest quality possible. Next to the development of reuse and repair strategies for photovoltaic system components, the license to operate for the PV value chain in the future will also rely on a strong circularity strategy when it comes to recovering materials and components from end-of-life photovoltaic systems. Given the longevi- ty of these components and a continued exponential de- ployment trajectory towards multi-terawatt scale by mid of the century, design for recycling becomes a critical prerequisite for technology development. In particular for new module and cell concepts – such as multi-junction technologies, combining thin-film compound semicon- ductors, and perovskites with silicon – recycling strategies need to be developed and findings of these developments need to be shared upstream to improve design concepts. Product circularity information needs to be readily avail- able to ensure the development of a low cost and widely accessible recycling infrastructure, embedded into existing WEEE recycling systems. To enable low-cost recycling, the inherent material value of secondary resources recovered from recycling needs to be valorised through a market pull for these materials. The development and definition of end-of-waste criteria for PV materials - be it scarce spe- cialty materials, high-embodied energy materials, or bulk commodity materials - will play a crucial role in convert- ing recovered waste fractions into marketable secondary raw materials for new PV production. Module design and material selection should encompass resiliency metrics, to ensure the acceptability of post-industrial and post-con- sumer recycled content.
From a holistic, life cycle environmental performance per- spective, these measures will help to further improve the environmental footprint of PV electricity - and as such, the downstream environmental footprints of power-to-X con- versions subsequently.
A majority of the lifecycle issues for PV systems can be improved through high value recycling:
| Impact category | Root cause for process issue |
|---|---|
| Mineral, fossil and renewable resource depletion | Supply chain of semiconductor materials (cadmium, tellurium, indium), silver (mainly used in metallization paste for multi- and mono-crystalline Si PV modules), copper (mainly used in the electric installation) and zinc (used in various processes such as secondary alumini- um production). |
| Human toxicity (cancer and non-cancer effects) | Cancer effects: disposal of redmud from bauxite digestion (supply chain of primary alu- minium) and disposal of slag generated in the production of unalloyed electric steel – sub- stance hotspots are chromium VI emitted to water and chromium emissions to air, both being primarily associated with the supply chain of steel production. Non-cancer effects: production of primary copper and zinc and related emissions from leaching residues and hard coal ash as well as zinc and mercury emitted to air in the pro- cess of unalloyed electric steel production and emissions of arsenic to water during the beneficiation of iron ore. |
| Freshwater ecotoxicity | Waste incineration of plastic components from the module and electric installation and the disposal of redmud from bauxite digestion (supply chain of primary aluminium). |
| Particulate matter potential | Supply chain of electricity, dominated by electricity production from Chinese hard coal power plants. |
| Acidification potential | Emissions of sulphur dioxide and nitrogen oxides to air due to operation of transoceanic freight ships, flat glass production and hard coal-based electricity production. |
Measures that enable and encourage a circular economy and the decarbonization of the electricity mix would help to effectively relieve some major hotspots by addressing resource depletion of critical materials in module manu- facturing, facilitating recycled content for primary materi- als in the BOS e.g. copper, steel, and aluminium, thereby reducing cumulative energy demand as well
Status
- End-of-Life recycling rate (EOL-RR) of Silicon (0 %), Indium (<1 %), Silver (~50 %, excluding jewellery)
- No recycling of polymers
- No / limited high value recycling of glass - end-of- waste criteria fulfilled, however, insufficient for re- use as float cullet
- High value recycling of CdTe semiconductor materi- al with 95 % re-use in new products established as best practice
- No/limited high value recycling of high purity silicon wafer or poly-silicon
Solar PV accounts for 10 % share in global silver consump- tion, 8 % for indium, and 5 % or less of the total production of MGS is used in the manufacturing of high-purity silicon for the solar and electronics industry.
Targets, Type of Activity and TRL
Recycling value chain analysis of materials in the PV and global value chain of other end-user applica- tions and prediction of PV share for these materials by 2030 and 2050.
Dedicated chemical (and mechanical) recycling processes for extracted polymers from PV module waste (TRL4-5)
Development of recycling processes for integrated PV with PV modules with variety of sizes, materials, etc. Creating clarity-link with construction element recycling sector.
Recovery of polymer fractions from PV module waste and further separation / sorting into the dif- ferent material types
Recycling of kerf: recovery of about 40 % of pure silicon, which is considered as waste when sawing a silicon ingot
Use of post-industrial and post-consumer recycled PV glass in new PV glass manufacturing
High value recovery of silicon from post-consumer end-of-life PV panels for material recovery in PV manufacturing / battery manufacturing / other sil- icon based industrial / material applications
Specific criteria in WEEE regulation to boost the re- cycling of precious metals
The role of digitalisation
End-of-life of products is regulated by an extensive frame- work, including the Waste Framework, WEEE and Batteries Directives. An online platform that provides treatment, re- cycling facilities, and preparation for re-use operators with access to WEEE recycling information in line with the re- quirements of the WEEE Directive.
This could be welcomed by recyclers as a valuable source of information enabling efficient recycling of EEE, provid- ing significant added value to the industry-supported col- lection schemes for end of life EEE. One example of such type of initiative is the Information for Recyclers Platform (I4R)
KPIs
| KPI | Target Value (2030) |
|---|---|
| Recycling of kerf | recovery of about 40 % of pure silicon |
| Recovery of polymers from PV module waste for chemical recycling | >90 % recovery of EVA, PVF, PVDF and PET |
| End-of-Life recycling rate (EOL-RR) | Silicon (90 %), Indium (30 %), Silver (70 %), |