Proper disposal of solar waste is vital for a sustainable future, preventing environmental harm and maximizing renewable energy's positive impact.

A recent study ‘Enabling a Circular Economy in India’s Solar Industry: Assessing the Solar Waste Quantum’ by the Ministry of New and Renewable Energy and independent think tank Council on Energy, Environment and Water (CEEW) has found that India’s solar waste could reach a massive 600 kilotonnes (kt) by 2030.

India’s installed 66.7 GW capacity, as of financial year (FY) 23, has generated about 100 kt of waste, which will increase to 340 kt by 2030, the study highlights. The Executive Summary of the study states India needs around 292 GW of solar capacity by 2030. With the rapid deployment of solar photovoltaic (PV) technologies, there are solar waste management concerns. Responsible solar PV waste management is critical for environmental, economic, and social reasons.

According to the CEEW website, solar waste refers to both discarded modules as well as scrap generated during the cell and module manufacturing processes. Modules can be discarded either when solar PV modules reach the end of their functional life or upon sustaining damages from activities such as transportation, handling and installation. Solar waste can be recycled to recover materials like glass, aluminium, copper, silicon and silver. Recycling can be broadly categorised into mechanical, thermal and chemical processes. Each process helps in the recovery of specific minerals of varying purity grades. Improper handling of solar waste and landfills should be avoided to reclaim valuable minerals from the waste and safeguard the environment from leaching of any toxic materials.

Around 67% of this waste is expected to be generated in five states: Rajasthan, Gujarat, Karnataka, Andhra Pradesh, and Tamil Nadu, according to the study. Rajasthan will account for 24% of the waste generated by 2030, followed by Gujarat at 16%, and Karnataka at 12%. Around 44% of the cumulative waste will be generated from new capacities. Cumulative waste will increase to about 19,000 kt by 2050; 77% of which will arise from new capacities. The discarded modules include minerals such as silicon, copper, tellurium, and cadmium, which have been classified as critical minerals for India by the Ministry of Mines. Recycling solar waste to recover these materials will reduce import dependency and enhance India’s mineral security.

The management of waste generated from solar PV modules, panels and cells is part of the Electronic Waste Management Rules 2022. The rules mandate solar PV module and cell producers to store the waste generated from solar PV modules and cells up to 2034-35 as per the Central Pollution Control Board (CPCB) guidelines. The rules also mandate the filing of annual returns on the e-waste management portal up to 2034-35. Every recycler of solar PV modules and cells shall be mandated for the recovery of materials as laid down by the CPCB.

Transitioning from a linear to a circular approach in the solar PV industry will create effective waste management practices and lead India toward a self-reliant and independent economy. The first step is to assess the solar PV waste quantum in the country. This study proposes a novel coefficient-based waste estimation model to estimate the solar PV waste generated from existing and upcoming installations. It also identifies major waste-producing regions across the country and the high economic value that can be obtained from the extraction of minerals from the waste PV modules.

The study adds that the solar PV waste management process, consisting of collection, transportation and recycling, can also lead to the creation of employment opportunities. Hence, its management is crucial from both resource management and socio-economic perspectives. A granular estimation of solar waste would help policymakers and industry players make informed decisions regarding the required regulations and infrastructure deployment. Although some studies provide estimates for India’s solar waste, they rely on global databases to ascertain the waste at the end-of-life of modules. A granular study that captures module degradation rates and replacement trends in Indian climatic conditions is crucial.

The CEEW study bridges the information gap in India-specific solar waste estimates by developing a comprehensive waste estimation model that provides the temporal and spatial distribution of solar waste. It further runs a comparative analysis across various scenarios by varying the module degradation rate and other available methodologies.