Enter Solar Industry: Error 404, Recycling not found!

SOLAR POWER

Enter Solar Industry: Error 404, Recycling not found!

Vishu Mishra and Dr.Parveen Kumar, TheCenter for Study of Science, Technology and Policy (CSTEP).

 Vishu Mishra  works as a Research Engineer at CSTEP and holds close to two years of association in Solar energy domain. His research work ventures in solar mini-grids in India and ground level implementation project of mini-grid technology in a remote village setting; a project undertaken by Good Energies foundation. He also represents CSTEP in it's knowledge partner association with International Solar Alliance's  solar mission road map of 121 nations.

Dr Parveen Kumar  is a Senior Research Scientist with close to four years of association with CSTEP. He has worked in solar energy domain, leading the Solar Energy Research Institute for India and United States (SERIIUS) project and worked on several policy and technology needs assessment.  He has previously worked as a Post-Doctoral Fellow at the Indian Institute of Science and has received a Ph. D. from Jamia Millia Islamia University.

In view of high renewable deployment, it is time for India to think about a circular economy that can reduce stress on critical materials, and support climate change mitigation efforts. An efficient recycling ecosystem can greatly help in sustainable economic growth through renewables, via employment generation and efficient utilisation of resources.

Background: High deployment & early losses

The Paris Climate Agreement at Conference of Parties (COP) 21 has driven the globe towards high renewable energy (RE) deployment and pledged an annual collective sum of USD 100 billion for mobilising RE action plans, up till 2020. India, too, under its Nationally Determined Contributions (NDCs) has set a high RE target of 175 GW by 2022. Solar is a major component of the RE target, with a share of 100 GW. Solar photovoltaic (PV) is one of the leading technologies used worldwide. A massive push for the deployment of this technology is coming from the private sector and in the form of policy support from the government. According to the International Energy Agency’s (IEA) 2016 report titled, “Snapshots of Global Photovoltaic Markets”, the current installed PV capacity across the world has leaped beyond 303 GW. It is expected to increase up to 1632 GW by 2030 and 4500 GW by 2050.

Currently, India has installed around 21 GW of solar PV. It translates to about 70 million installed PV panels with no existing plans for their end-of-life management issues, such as e-waste dumping, recycling and reuse. Since the current policy objectives focus wholly on deployment and installations, recycling aspects for creating a circular economy are not mooted in current discussions.

Although, shifting from conventional sources to renewables is definitely the bright side of the coin, there is a flip side; technological stresses on certain resources. For example, promising solar thin film technologies require potentially critical minerals such as indium, gallium and selenium. The high requirement for these materials leads to large-scale and often unsustainable extraction practices, which puts pressure on the reserves of these materials and contributes to greenhouse gas (GHG) emissions.

The International Renewable Energy Agency’s (IRENA) report, titled “End of life management: Solar Photovoltaic Panels”, includes a lateral analysis of regular loss versus early loss scenarios for the lifecycle of PV panels. It remarks that the promising life span of 25–30 years is theoretical as it involves factors that lead to failures at multiple stages, thereby causing early retirement of the modules.

Upon inspecting the panels (Fig. 1), failures were found at various life-stages, such as infant stage (due to incompetent mounting), bad support construction and electrical failures (19%); causes of midlife failure include degradation of glass coating (20%), delamination (5%) and cracked cell isolation (10%); and later-stage failures can be attributed to defects such as micro cracks in the cells. These defects were found in 40% of the examined thin cell panels, manufactured after 2008. All the above-mentioned factors indicate early loss scenarios.

Figure1: Main causes of PV panel failure

Sources: IRENA & IEA-PVPS, 2016; IEA-PVPS, 2014

On-site issues, local factors and shortened life span

There are various on-site issues, which make the need for a recycling policy imperative. The discrepancy between a technician’s installation and manufacturers’ installation guidelines lead to early losses. These include factors such as wrong sizing, improper grounding and unfavourable operating conditions. For example, optimum module operation is difficult in high salinity areas, close to maritime boundaries, because the climate hostility brings upon faster panel deterioration. Similarly, in windy places, where dust and micro-particles accumulate perpetually, panels may require high maintenance work. Such issues, not only make the producers’ warranties void in many cases, but usually lead to delayed, marginal or no replacement at all. Therefore, an identifiable vicious cycle exists at the site end.

There are other local factors that exist in the immediate vicinity of the panels. For example, we can easily observe defunct, pole-mounted solar PV panels for street lighting in our areas. Their operational failure is largely due to a combination of both, a lack of maintenance and effects of the local environment. Local causes that degrade the life of panels include soiling losses (with dust, pollen, or snow accumulating on panels) and soiling patches from leaves and bird droppings that create hot spots. These, coupled with poor maintenance, aggravates the damages manifold. Such compounding effects are detrimental to the prospective deployment of renewables, such as solar PV. Therefore, these factors need to be acknowledged and addressed, in a pragmatic and timely manner. Necessary steps must be taken to deter the emergence of a major e-waste problem.

Recycling industry: Imminent needs & upcoming technologies

Crystalline Silicon (c-Si) panels dominate global solar installations by over 90%. Each panel weighs up to 18–20 kg, on an average. The IEA has estimated a global PV panel waste pile-up in early and regular loss scenarios. In a regular loss scenario, it will be in the range of 1.7 million tonnes by 2030 and 60 million tonnes by 2050. While In the early loss scenario, the projected pile-up will be much higher, at 8 million tonnes by 2030 and 78 million tonnes by 2050. Therefore, the need for a robust recycling framework is fast emerging as a crucial requirement for ensuring the sustainability of solar technology usage.

The standard efficient recycling processes, such as FRELP (Full Recovery End of Life Photovoltaic) process, can recover up to 90% of the clean glass and 95% of semiconductor materials from a retired module. The major components from PV waste can be separated and recovered as glass (70%), aluminium (18%; from the PV frame), silicon (approx. 3.5%; metallurgical grade, extracted from the cell), encapsulation layer (approx. 5%; polymer-based adhesive), back-sheet layer (1.5%; based on polyvinyl fluoride), cables (1%; containing copper and polymers), metals (around 0.7%; aluminium, copper, silver, tin, lead and antimony, which are present in glass) and other minor yields.

The recycling ecosystem will not only help limit the release of toxic elements such as lead and antimony into the environment, but also create a value cycle from raw material recovery. However, these processes are energy intensive and need to be improved in the coming years for larger magnitudes of waste. For example, the FRELP process employs large amounts of water (around 309 kg per 1000 kg of PV waste) for undertaking operations such as acid leaching, electrolysis and neutralisation. It also expends heavily on electricity usage (approx. 114 Kwh for 1000 kg of PV waste) for processes such as disassembly, glass separation, sieving, leaching, etc.

Recycling is not just about sustainability; the recovery and reuse protocol is a great economic opportunity too. As per IRENA, recycling is estimated to become a USD15 billion industry by 2050 worldwide. Interestingly, this estimate only accounts for raw material recovery and it is a highly expansive proposition in potential. As per IRENA’s projections, the potential raw material recovery equates to about 60 million new panels or 18 GW of equivalent installed capacity by 2030, and 2 billion new panels or 630 GW of equivalent installed capacity by 2050. In light of this discussion, a unanimous opinion must stress on recycling needs in the activities of the global solar industry. A global agreement can be followed by expedient policy actions in all country, with a mandate for creating region-specific frameworks for a circular economy. There are many exemplary steps that have been taken around the world. For example, the European Union’s Waste Electrical and Electronic Equipment (EU-WEEE) Directives impose recycling requirements on solar panel manufacturers and mandate the fabrication of new panels using recycled components, such as silicon wafers from solar cells. New, sustainable technologies for silicon wafer manufacturing are being developed at the Korean Electronics Technology Institute. The process bypasses the use of toxic chemicals such as hydrofluoric acid and recovers good quality silicon wafers to build new solar cells. The performance of these solar cells is similar to any other.

Why act now?

One might wonder that when our solar industry is still in its nascent stages, why worry about recycling right now? India needs to remember the lessons learned from its e-waste problems. Since 1985, there has been a high rate of computer deployment, without any focus on efficient recycling ecosystems. As a result, we are now facing a huge problem of e-waste disposal. As per a United Nations Environment Programme (UNEP) report, India will face a 500% jump in computer e-waste and 18 times jump in mobile phone e-waste, by 2020. Improper disposals have not only led to loss of critical materials, but also contamination of the environment with elements such as lead, mercury and cadmium.

Considering that India alone is expected to pile up 3.25 lakh tonnes of e-waste (electrical and electronic waste) from solar PV panels (including glass, silicon, critical metals, etc.) by 2030, it is imminent that a recycling industry for solar PV be created. At present, degraded modules are disposed through unorganised e-waste collectors in India. The lack of a policy means that non-industrial waste, such as solar PV modules are not classified and they eventually end up in illegal dump sites and landfills, adding to India’s carbon footprint and contaminating the environment. As per the Indian E-waste Rules of 2016, by the Ministry of Environment, Forest and Climate Change (MOEFCC), the e-waste infrastructure is defined for industrial-scale e-waste, but only covers household electronics and not solar PV modules.

Conclusion: Bright examples & a new paradigm

Although most nations classify retired solar panels as general or industrial waste, there are global best practices that can be followed. EU’s regulations enforce end-of-life collection upon suppliers and these processes are inclusive of recycling costs. In Japan, home appliances are issued with recycling tickets, which allow ease of data monitoring of electronic equipment. Similarly, the Chinese stress on high reuse, low treatment, and they strongly control illegal dumping.

India can learn from these examples, to set a benchmark for our near-future aspirations. This can be done in many ways. For material reduction, thinner silicon cells can reduce the amount of silicon used in c-Si cells, i.e., by moving to a back contact cell design, the use of silicon can be cut by half and energy consumption reduced by 30%. For reuse, a modestly used PV panel market can be created in India, which brings down the cost of panels purchased through secondary markets and creates repair service jobs in India.

To establish the recycling ecosystem, we can impose a producer financed compliance fee or consumer financed end-of-life fee, to create a financial model for closed loop recycling processes such as collection, treatment, recovery, and disposal. This new industrial space in India will put extended producer responsibility (EPR) on manufacturers, for end-of-life management and the PV recycling processes will yield good employment opportunities in the public and private sectors.

Further, the silicon extracted from the used panels can serve as an alternative to fill the gap for domestic manufacturing of polysilicon. It is well-argued that setting up a polysilicon industry is capital intensive and due to the absence of upstream manufacturing processes for ingots and wafers, the solar industry’s growth is import dependent, and hence stinted, in India. Here, the concept of circular economy can serve well as a cost effective and sustainable growth alternative.

Further, an efficient recycling ecosystem will greatly help in reducing the loss of critical materials. It will promulgate our collective efforts in climate change mitigation, in a more holistic manner. We must embark on this aspirational journey, keeping in mind these three tenets of waste management. Our endeavours must stay put on sustainability in the age of neo-energy transformation.