Recommendations :

1. SALVAGE VALUE OF PHOTOVOLTAIC SYSTEMS Lalita Nayagam, ZuhairAlmumattin MAE 598 Solar Commercialization Mentor: Steven Trimble, Ronald Roedoel School for Engineering of Matter, Transport and Energy Recycling Process: • Basic Concepts and Steps: • Process: • Modules are shredded into large pieces before being crushed by a hammer mill to pieces typically smaller than 5 mm in order to break lamination bonds. • Semiconductor films are removed in a slow rating leach drum in a process taking 4–6 hours. • Weak sulphuric acid and hydrogen peroxide is added to the glass to achieve an optimal solid-liquid ratio. The films are etched from the glass during the leach cycle. • Glass is separated from the liquids in a classifier. • The material is then moved to a vibrating screen separating the glass from the larger ethylene vinyl acetate (EVA) pieces. • The EVA is deposited into another conveyor and collected, whereas the glass falls through the screen to a chute where it is taken to the rinsing step; • After being cleaned, the glass is deposited into containers for recycling and the rinse waters are pumped to a precipitation system for metal recovery; • The metal compounds are precipitated in three stages at increasing pH using sodium hydroxide. When the solids have settled and been made into a metal rich filter cake, it is sent off for processing by a third party where they can be processed to semiconductor grade raw materials for use in new solar modules • The cost of the process is about $3/KW • Table: Percentage recovery from Salvaged Photovoltaic • Ref: Renewable Energy magazine, April 2014 • Currently, economic incentives may be inadequate to move the PV industry into voluntary recycling. However, this may change in future, as more economic incentives may be given to developing clean technologies and reducing carbon dioxide emissions. • Several States have started programs in support of recycling electronic equipment; discarded electronics are described as resource instead of waste and the States assist in building up recycling infrastructure and market To answer the following questions: Is it possible to salvage PV? Are the processes involved efficient What are the barriers in the salvaging process Who can make it possible. Is the process paying for itself What policies are required to get this done? • Policyimplications: Goal: • Conclusions: • Based on the study we realised that Salvaging PV is technically possible but not economically feasible as of today. • There are no government incentives to promote this In dispersed operations, small quantities and high transportation costs make this option relatively expensive deal. • The processes are not extremely efficient hence increasing the cost in the market • But recycling PV is extremely favorable to us in the long term • Introduction: • Modules are expected to last about 30 year • There is a concern about disposing them in municipal landfills because they may contain small amounts of regulated materials (e.g., Cd, Pb and Se) • Recycling PV systems at the end of their useful life adds to the environmental benefits and can further enhance market support • Recycling answers public concerns about hazardous materials in PV modules which can create barriers to market penetration. • The feasibility of collection and recycling of spent PV modules is explored in this paper Fig . PV Scrap and Module recycling options Barriers in Process: • Recommendations: • Policies must be introduced such that the recycling costs will not be a market barrier for the system. Currently, the prices are significantly high • Policies must be introduced for the collection and disposal or recycling is proportional to the weight of the recycled materials • Battery recycling program especially for residential solar must be introduced • Environmental disposal and waste handling regulations, logistics and economics of product recycling and waste disposal affect the reasoning and practicality of recycling. • Absence of streamlined methodologies for home owners and other PV installers. • Absence of enforced government policies • Cost of the salvage process is not self paying • Inefficient processes • Improper disposal-which is cheap-its extremely harmful to the environment • Unavailability of economic incentives • In dispersed operations, small quantities and high transportation costs make this option relatively expensive. Ref: First Solar website