Ingersoll-Rand vacuum business helps the photovoltaic industry to create a sustainable future together

Vacuum technology is widely used in the photovoltaic industry. Solar energy resources are abundant and widely distributed, and it is the most promising renewable energy source. With the increasing problems of global energy shortage and environmental pollution, solar photovoltaic power generation has become an emerging industry of universal concern and focus on development in the world because of its clean, safe, convenient and efficient features.

At the same time, along with the carbon peak and carbon neutral topic, the PV industry ushered in a big development, more and more companies focus on product technology testing method and production process optimization. At the same time, "cost reduction" has become an important step in whether PV can surpass other clean energy sources and become a major power generation facility. 

Vacuum technology and products can more effectively help users to realize the role of cost reduction and efficiency and increase profits.

 
Image: Photovoltaic industry chain
Source: Foresight Industry Research Institute

Vacuum applications in the photovoltaic industry.
Conveying process: In the production of PV modules process, vacuum technology is needed to achieve efficient and precise workpiece handling (e.g. wafers, cells, packaging lines and finished modules)

Monocrystalline wafer production - crystal pulling process: used in sintering furnaces for monocrystalline and polysilicon to prevent contamination by impurities, prevent reactions with other gases and improve crystal pulling purity
Equipment: Single crystal furnace
Growth conditions: must be under vacuum conditions or protective atmosphere to avoid oxidation
Composition: Overall six parts: furnace body, electrical part, thermal system, water cooling system, vacuum system and argon gas supply device

Solar cell production - etching process: The doped silicon around the solar cell is etched to avoid the flow of photogenerated electrons collected on the front side of the PN junction to the back side of the PN junction along the edge diffusion with phosphorus, which causes a short circuit.
Solar cell is a semiconductor device with energy conversion function based on semiconductor material, which is the most core device of solar photovoltaic power generation.
Silicon solar cells (monocrystalline silicon solar cells, polycrystalline silicon solar cells, amorphous silicon solar cells), thin film solar cells, compound solar cells, organic semiconductor solar cells

Solar cell module production - lamination process: expel the air in the gap of the packaging material and the gas generated during the lamination process to eliminate the air bubbles in the module; create a pressure difference inside the laminator to generate the pressure required for lamination
Laminator: The laminated cells are placed inside the laminator and the air inside the module is extracted by vacuuming, then heating melts the EVA to bond the cells, glass and backsheet together; finally the module is cooled and removed.


Vacuum Solution
Crystal pulling process
Precautions.
Stability of the environment is required during the crystal pulling process - the ultimate vacuum and load resistance of the vacuum pump is tested, which can mix with the pump oil and cause degradation of the vacuum pump performance
Impurities and silicon oxides are generated during crystal pulling - Pump oil


Process requirements.
Ultimate vacuum: less than 0.03 mbar
Vacuum requirement during crystal pulling: around 15 mbar

Main products.
Dry screw vacuum pump VS
 

Reason
High ultimate vacuum capacity
High performance, high load resistance
No pump oil required, reduced maintenance costs


Laminated process
Caution.
Characteristics of EVA adhesive - EVA adhesive is mixed with pump oil by impurities generated with high temperature, causing performance degradation
Continuous production around the clock, to ensure that the PV module is absolutely flat and free of air or gas entrainment - Performance
The higher the vacuum level in the lamination process, the better the quality and the longer the life of the PV module - Vacuum level


 

Process requirements.
Ultimate vacuum: 1 mbar
Laminate temperature above 140°C

Laminate chamber & curing chamber Main products.
Dry screw vacuum pump vs.
 

Reason
No need for any working fluid
Close to high vacuum
Less maintenance cost than oil pumps
Secondary heat transfer / indirect cooling (direct cooling leads to excessive temperature differences, indirect cooling avoids this problem)

Cooling chamber Product recommendation.
VLR series claw vacuum pump
 
Reasons.
Anti-corrosion capability - built-in molybdenum sulfide/PTFE coating, any condensate can be freely discharged downward
High performance
Low life cycle cost
At Ingersoll-Rand, we are constantly innovating to bring more efficient, energy-saving and green solutions to the photovoltaic industry, creating value for our customers with a strong commitment to sustainability.

Trust us to make your life better.