Thinner, more-efficient solar cells
Using high-power particle physics, Rayton Solar engineers demolish material waste in solar panel manufacturing – cutting costs by 68% while boosting efficiency.
Founder and CEO Andrew Yakub started Rayton Solar in 2012, recognizing that the solar industry needed a strong solution before government subsidies end in 2016. He decided to stop relying on fluctuating market prices with his solar financing company, ReGen America, and manufacture his own solar cells. As a particle accelerator physicist at UCLA, he learned about a forgotten technology developed in the early 1990s that uses ion implantation and layer transferring. Since no other solar cell manufacturer used this method at the time, he decided to improve the process, make it economically optimal for the solar industry, and patent his ideas with Rayton Solar.
Solar cell manufacturing
To achieve Yakub’s solar cell manufacturing goals, he needed a method for implanting float-zone silicon – a very pure type of silicon often used in lenses – with hydrogen ions and exfoliating a thin layer. Yakub and other engineers at the company designed and tested several manufacturing processes to achieve this as well as an accelerator technology for the application.
“We use an accelerator that operates at 300KeV and thus we can exfoliate a 4.7µm thick layer of float-zone silicon,” Yakub explains. “We are currently using this accelerator to produce enough material to be used in a complete solar module that can then undergo Underwriters Laboratories (UL) certification.”
Once Rayton Solar implants the silicon, exfoliates the thin layer, and attaches it to a lamina for support, the engineers produce a wafer that can undergo conventional manufacturing techniques – including off-the-shelf machinery to create cells and then assemble them into a module.
Particle accelerator
The particle accelerator works by taking hydrogen gas in a resonant microwave chamber and ionizing the gas into ions and electrons. Because of the applied electric field, the H+ (protons) go one way and the electrons go the other way since they have opposite charges.
“This microwave chamber uses a concept called electron cyclotron resonance to ionize enough protons to hit a current that is 1,000x higher than anything else available on the market,” Yakub says. “The protons leave the microwave ion source and enter the acceleration chamber. This is just an electric field gradient that accelerates the beam of protons to 300KeV. Once they leave the acceleration chamber, we aim them into our silicon ingot for implant.”
Rayton Solar uses only monocrystalline silicon as the sunlight absorber in its cells. Yakub says monocrystalline silicon has the highest efficiency compared to polycrystalline silicon and is non-toxic unlike thin film technologies such as cadmium telluride (CdTe) or copper indium gallium selenide (CIGS).
To complete its solar cell, the company use thin layers (sub microns) of other materials such as an anti-reflective coating made of silicon nitride (Si3N4), amorphous silicon layers for a back surface field, and silver wire for the cell’s front contacts.
Less COSTLY, more efficient
By using a 4.7µm layer of silicon rather than a traditional 200µm layer, and exfoliating directly off an ingot, Rayton Solar has seen a reduction in the raw silicon used per wafer.
“This translates to an overall 68% reduction in the cost to make a solar panel,” Yakub explains. “By using a higher quality silicon, float-zone silicon, we see a 25% boost in efficiency. Since float-zone silicon costs 10x more than solar grade CZ silicon we can only do this because we are using a 4.7µm thick layer of float zone. Other manufacturers are economically unable to use float-zone silicon.”
“We are currently 12 to 18 months away from opening our 6MW per year manufacturing facility. We would like to keep this in Los Angeles county, but we have been approached by various municipalities in the Midwest that can offer incentives to manufacturers,” Yakub says.
Yakub says Rayton Solar will keep its manufacturing in the United States, as that was one of his goals with funding the company.
“I want to stimulate the U.S. economy with high-tech manufacturing of renewable sources of energy to create a better future for society,” Yakub says. “I believe the future of the energy industry will have solar electricity generation at its core. Large companies will begin to adopt solar as a mainstream source of energy. This will happen before 2050, as the International Energy Agency has predicted that the majority of electricity will come from solar by 2050. Companies like Rayton will help speed this up.”
http://www.onlinetes.com/article/tes1215-solar-cells-manufacturing-particle-physics
Using high-power particle physics, Rayton Solar engineers demolish material waste in solar panel manufacturing – cutting costs by 68% while boosting efficiency.
- December 10, 2015
- Arielle Campanalie
Solar cell manufacturing
To achieve Yakub’s solar cell manufacturing goals, he needed a method for implanting float-zone silicon – a very pure type of silicon often used in lenses – with hydrogen ions and exfoliating a thin layer. Yakub and other engineers at the company designed and tested several manufacturing processes to achieve this as well as an accelerator technology for the application.
“We use an accelerator that operates at 300KeV and thus we can exfoliate a 4.7µm thick layer of float-zone silicon,” Yakub explains. “We are currently using this accelerator to produce enough material to be used in a complete solar module that can then undergo Underwriters Laboratories (UL) certification.”
Once Rayton Solar implants the silicon, exfoliates the thin layer, and attaches it to a lamina for support, the engineers produce a wafer that can undergo conventional manufacturing techniques – including off-the-shelf machinery to create cells and then assemble them into a module.
Particle accelerator
The particle accelerator works by taking hydrogen gas in a resonant microwave chamber and ionizing the gas into ions and electrons. Because of the applied electric field, the H+ (protons) go one way and the electrons go the other way since they have opposite charges.
“This microwave chamber uses a concept called electron cyclotron resonance to ionize enough protons to hit a current that is 1,000x higher than anything else available on the market,” Yakub says. “The protons leave the microwave ion source and enter the acceleration chamber. This is just an electric field gradient that accelerates the beam of protons to 300KeV. Once they leave the acceleration chamber, we aim them into our silicon ingot for implant.”
Rayton Solar uses only monocrystalline silicon as the sunlight absorber in its cells. Yakub says monocrystalline silicon has the highest efficiency compared to polycrystalline silicon and is non-toxic unlike thin film technologies such as cadmium telluride (CdTe) or copper indium gallium selenide (CIGS).
To complete its solar cell, the company use thin layers (sub microns) of other materials such as an anti-reflective coating made of silicon nitride (Si3N4), amorphous silicon layers for a back surface field, and silver wire for the cell’s front contacts.
Less COSTLY, more efficient
“This translates to an overall 68% reduction in the cost to make a solar panel,” Yakub explains. “By using a higher quality silicon, float-zone silicon, we see a 25% boost in efficiency. Since float-zone silicon costs 10x more than solar grade CZ silicon we can only do this because we are using a 4.7µm thick layer of float zone. Other manufacturers are economically unable to use float-zone silicon.”
“We are currently 12 to 18 months away from opening our 6MW per year manufacturing facility. We would like to keep this in Los Angeles county, but we have been approached by various municipalities in the Midwest that can offer incentives to manufacturers,” Yakub says.
Yakub says Rayton Solar will keep its manufacturing in the United States, as that was one of his goals with funding the company.
“I want to stimulate the U.S. economy with high-tech manufacturing of renewable sources of energy to create a better future for society,” Yakub says. “I believe the future of the energy industry will have solar electricity generation at its core. Large companies will begin to adopt solar as a mainstream source of energy. This will happen before 2050, as the International Energy Agency has predicted that the majority of electricity will come from solar by 2050. Companies like Rayton will help speed this up.”
http://www.onlinetes.com/article/tes1215-solar-cells-manufacturing-particle-physics
