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N. Jariwala and J. Soni
9.3 Methodology
PV modules have a long working life (on an average 30 years) and have been installed
predominantly in large-scale (>1 MW) systems in most counterparts, particularly
since the mid 2000s. “As these long-lived PV systems mature, it is anticipated that
large quantities of PV modulus waste will be produced by the year 2030. Endof-life management with resource recovery is preferable to recycling as a way of
managing end-of-life PV systems with respect to environmental impacts and energy
use” [20]. Recycling not only eliminates waste and waste-related pollution when recycling processes themselves are successful, but also provides the ability to minimize
the energy usage and pollution associated with the processing of virgin materials.
“This may be particularly important for raw materials with high levels of impurity
(e.g., semi-conductor precursor material), which often require an energy-intensive
pretreatment to achieve the required levels of purity. Recycling is also important
for the long-term management of resource-constrained metals used in PV modules”
[21].
Till date, aging or damaged solar panels have typically been recycled in all-purpose
glass processing plants, where only their glass and aluminium frames are recovered,
and their specialist glass combined with other glasses. Typically the left over is then
burned in cement stoves. So are solar panels completely recyclable? The short and
simple answer is “yes.” “Essentially, silicon PV modules are made of glass, plastic,
and aluminium: three materials that can be recycled in massive quantities. Given the
recyclability of the PV modules, the process of separating materials may be tedious
and involves modern machinery and technology”[22].
Below are the four basic steps for efficient recycling of a silicon module:
1. The aluminium frame (100% reusable) could be removed.
2. Separating the glass by means of a conveyor belt (reusable 95%).
3. Thermal treatment with temperature of 500 °C. It allows the tiny plastic
components to evaporate which allows for quick separation of the cells.
4. Etching away and smelting silicon wafers into reusable slabs (reusable 85%).
“A variety of methods are currently being developed for extracting useful metal
components from PV wastes. Several process steps need to be incorporated to remove
the metal frame, back panel, EVA resins and protective tempered glass coating before
recovery of the PV modules” [23]. “The most successful recycling method to date for
c-Si PV modules is focused on mechanical, thermal and chemical processes” [17].
“The new state-of-the-art recycling process aims to recycle more than 80% of the PV
module by weight. For the recovery of value-added components or products, EoL
products or scraps collected under various schemes are shipped to the consolidation
sites” [8].
The method flow starts with aluminium frame disassembly and junction box disassembly. Since the size, profiles, and frame fastening vary from one maker to another,
frame disassembly is often performed manually. Then shredded, sorted, and separated after frame. The materials isolation allows them to be sent through different
N. Jariwala and J. Soni
9.3 Methodology
PV modules have a long working life (on an average 30 years) and have been installed
predominantly in large-scale (>1 MW) systems in most counterparts, particularly
since the mid 2000s. “As these long-lived PV systems mature, it is anticipated that
large quantities of PV modulus waste will be produced by the year 2030. Endof-life management with resource recovery is preferable to recycling as a way of
managing end-of-life PV systems with respect to environmental impacts and energy
use” [20]. Recycling not only eliminates waste and waste-related pollution when recycling processes themselves are successful, but also provides the ability to minimize
the energy usage and pollution associated with the processing of virgin materials.
“This may be particularly important for raw materials with high levels of impurity
(e.g., semi-conductor precursor material), which often require an energy-intensive
pretreatment to achieve the required levels of purity. Recycling is also important
for the long-term management of resource-constrained metals used in PV modules”
[21].
Till date, aging or damaged solar panels have typically been recycled in all-purpose
glass processing plants, where only their glass and aluminium frames are recovered,
and their specialist glass combined with other glasses. Typically the left over is then
burned in cement stoves. So are solar panels completely recyclable? The short and
simple answer is “yes.” “Essentially, silicon PV modules are made of glass, plastic,
and aluminium: three materials that can be recycled in massive quantities. Given the
recyclability of the PV modules, the process of separating materials may be tedious
and involves modern machinery and technology”[22].
Below are the four basic steps for efficient recycling of a silicon module:
1. The aluminium frame (100% reusable) could be removed.
2. Separating the glass by means of a conveyor belt (reusable 95%).
3. Thermal treatment with temperature of 500 °C. It allows the tiny plastic
components to evaporate which allows for quick separation of the cells.
4. Etching away and smelting silicon wafers into reusable slabs (reusable 85%).
“A variety of methods are currently being developed for extracting useful metal
components from PV wastes. Several process steps need to be incorporated to remove
the metal frame, back panel, EVA resins and protective tempered glass coating before
recovery of the PV modules” [23]. “The most successful recycling method to date for
c-Si PV modules is focused on mechanical, thermal and chemical processes” [17].
“The new state-of-the-art recycling process aims to recycle more than 80% of the PV
module by weight. For the recovery of value-added components or products, EoL
products or scraps collected under various schemes are shipped to the consolidation
sites” [8].
The method flow starts with aluminium frame disassembly and junction box disassembly. Since the size, profiles, and frame fastening vary from one maker to another,
frame disassembly is often performed manually. Then shredded, sorted, and separated after frame. The materials isolation allows them to be sent through different