Image Generated by Adobe Firefly.
Advancements in PV Market Exploring the Future of Solar Energy
Vinodhini Harish
22 Jul 2024
Introduction:
How often do you see solar panels on rooftops, they are made of PV cells working together to generate electricity. The emission of pollutants like sulphur dioxide, nitrogen oxides, and particulate matter, caused by using fossil fuels and other non-renewable resources has encouraged industries to generate energy from renewable resources. If you are interested in what the future holds for the renewable energy sector and photovoltaic cell industry, we have covered interesting facts, innovation in the industry and other aspects leading to the growth of the photovoltaic industry. We have also shared some insights on the impact it creates on the chemical industry. Let’s get started.
Advancements in photovoltaic cell materials:
The advancements made in the photovoltaic cell materials from which they are fabricated made a significant difference in the pursuit of sustainable energy solutions. Therefore researches were conducted to explore the characteristics of the silicon-based photovoltaic cells, polycrystalline silicon cells and Gallium arsenide solar cells.
The research covers the challenges due to material stability, scalability and environmental impact and explores the types of PV cells such as silicon-based cells which are explored for their enduring relevance and recent innovations in their crystalline structures. The flexibility and potential for low-cost production of organic photovoltaic cells and remarkable efficiency gains and ease of fabrication of perovskite cells.
- Silicon-based photovoltaic cells: The dominance of silicon in PV is due to several key factors such as silicon being the second most abundant element in the earth's crust. Therefore, they are readily available for solar cell production. The abundance has made widespread adoption and scalability possible. Secondly, the semiconductor properties of silicon make it an ideal material for converting solar energy into electricity. Additionally, the bandgap is quite appropriate for absorbing the broad range of the solar spectrum and maximizing energy conversion and efficiency.
Therefore, the recent research aimed at transcending the traditional efficiency limits and the structure of perovskite top cells, intermediate interconnection layers and crystalline silicon bottom cells were given additional focus.
Furthermore, the study by Xie Et al reported significant advancements in the efficiency of the silicon solar cells, that are derived from the thin crystalline silicon solar cells which are considered a promising alternative to the conventional thicker c-Si solar cells due to their cost-effectiveness and flexibility.
Although there are several advantages to the usage of silicon in photovoltaic technology, such as the abundance of silicon and well-established manufacturing processes, the limitations concerning the efficiency and complexities involved in the production processes have paved the way for the exploration of alternative materials.
Perovskites: Perovskites have gained momentum in photovoltaic technology due to their substantial power conversion efficiencies. They are known for their lower production costs, easier fabrication methods, economically attractive for the photovoltaic market players.
For instance, these materials can be produced using simple production techniques such as solution processing, they are less energy-intensive and cheaper compared to the conventional silicon methods. It is easier to optimize the light absorption by tailoring them at the molecular level which is considered very crucial in enhancing the solar cell efficiency.
Quantum dots: The quantum dots solar cells can be engineered to create solar cells with multi-junction and they utilize tiny semiconductor particles whose bandgaps are tunable based on the required size. This enables the cells to absorb different wavelengths of light more efficiently compared to traditional materials.
Gallium arsenide GaAs solar cells: at present GaAs cells are considered the most efficient solar cells available today. Since the direct bandgap of GaAs allows efficient absorption of sunlight and conversion into electrical energy, they are more efficient than silicon-based solar cells and they have surpassed 29%, which is the benchmark set in controlled laboratory conditions. Furthermore, the unique properties of GaAs solar cells make them appropriate for space applications. For instance, they are highly efficient when coupled with a resistance to radiation, which ensures long-term operation even in the harsh environment of space.
However, there are other materials added to the list of innovations in the photovoltaic cell technology which includes tandem solar cells, building-integrated photovoltaics and concentrated photovoltaic systems. Overall the outlook of photovoltaic materials is quite dynamic and very promising.
How the photovoltaic cell market is combating the challenges:
Challenges for the photovoltaic cell market arise due to the scarcity and production cost of the materials used. Now, the most efficient Gallium used in modern photovoltaic cells is a byproduct of the smelting of other materials such as aluminum and zinc. Therefore, the availability of Gallium is highly dependent on the production levels of these metals, and extraction processes of Arsenic which is more abundant yet poses environmental and health risks during extraction and processing, necessitating stringent handling and disposal measures.
Therefore the industry players are making efforts to address the cost and material scarcity challenges involved in the production of GaAs solar cells. They have come up with innovations in manufacturing techniques such as the development of thin-film GaAs solar cells that also aims to reduce the materials usage and production costs. The thin-film technology has enabled the deposition of GaAs layers on the inexpensive substrates which significantly lowers the amount of gallium and arsenic required for the production.
New chemical synthesis method to improve organic solar cell efficiency:
Organic solar cells are steadily improving in their efficiency and affordability due to the new advances in technology. One specific promising approach is boosting the performance by using specialized polymers that are called “Polyelectrolytes”. Although these materials have proven difficult to produce with the expected levels of purity required for the production of OSCs, new research was conducted in South Korea, by colleagues of Pukong National University at Busan, South Korea. They have worked in synthesizing high-purity polyelectrolytes and applying them to OSCs.
The unique electronic structure of polyelectrolytes enables the boost in efficiency which is performed by collecting the electrons generated in the active layer while lowering the resistance of the flow of electrons from the active layer to the cathode. However, the challenge involved is that during the polyelectrolyte production that is deployed presently, the removal of excess starting materials remains a laborious and time-intensive task. Therefore this new chemical synthesis proposes a simpler purification method eliminating the requirements of excess starting materials.
The research is conducted by Joo Hyun Kim and his colleagues, and he describes that they have introduced an ion exchange technique for modifying the polymers and then utilizing them as cathode interlayers in OSCs. Therefore the results of these researches suggest that polyelectrolytes exhibit greater potential and eliminate time-consuming purification process, thereby being applied more widely and accelerating the rolling out of renewable solar energy and reducing the reliance on fossil fuels.
New photovoltaic leaf (PV-leaf) technology:
Chemical engineers at Imperial College London have come up with photovoltaic cell technology that lowers the cost yet generates a 14% increased amount of electricity compared to conventional solar panels.
This technology has addressed the core problem that exists in photovoltaic cell technology, which is the capability of converting only 10-25% of incident solar energy that is captured by a PV is converted into electricity. What happens to the rest of the unusable solar energy then?
it is dissipated as waste heat in PV cells and increases the operating temperature. The challenge arises just there when the operating temperature rises above 65°C, then it significantly decreases the electrical efficiency.
The chemical engineers at Imperial College in London, have tried to mimic the movement of water through the veins of any plant leaf. The technology encompasses the idea of transpiration and developed the device made of a biomimetic transpiration layer that contains bundles of bamboo fibres and packets of hydrogel cells.
The fibre layer is about 1mm thick which is sandwiched between a steel wire mesh on a base and 10cm x 10 cm solar cells on the top. Then the root of the fiber bundles are let to soak in a water tank. Now these bamboo cells act as plants siphoning water up from the tank and spreading it across the underside of the solar cells. As the water evaporates, the heat is drawn away from the solar cells allowing the leaf panels to cool down without needing any additional energy. The team in their research paper mentioned that the technology is capable of removing about 75% of heat from the system and decreasing the operating temperature by approximately 26°C. Thus these two factors combined to give an improved output in the electricity by approximately 14%.
In addition to that the system is capable of utilizing saline water instead of fresh water as a coolant, which contributes to an advantage in the areas where freshwater is scarce. Thus the innovative design holds great potential in improving the electricity efficiency while keeping up the performance of the panels.
Countries embracing abundancy, sustainable and clean solar energy:
A recent report by the International Energy Agency declared that renewable energy capacity is expected to grow by nearly 95% by 2026 and solar energy is expected to be a dominant contributor with its cumulative capacity set to almost triple, growing by nearly 1500 gigawatts by 2027. The substantial contribution from solar energy highlights the importance of upgrading photovoltaic technologies and every effort to transition away from fossil fuels.
Photovoltaic cell markets taking turns, lows and shifts:
The photovoltaic cell market was looking for a good solar material whose crystal structure is appropriate for solar absorption. Perovskite cells are the ones that work better than silicon even at lower light intensities, on cloudy days, indoors and thereby increasing conversion efficiency to a remarkable level.
Presently the top-tier N-type solar panels have dropped to 0.1- 0.114 USD per watt and the price of P-type PERC solar panels has dropped to 0.106 USD per watt from 0.1. The leading companies that produce solar panels have halted their production lines for P-type solar panels and the product inventories have dropped as well. So the PV market is witnessing significant price reductions across the globe. Also presently the price for these modules is around 0.11 USD per watt.
The supply side has also slowed down a bit and the production is reduced as well. Even some of the leading global companies have dropped their production by about 50%. But the demand side is at the mid-level too as the buyers are playing wait-and-see cards till then they will consider making their purchases once the prices hit the bottom.
China dominates the global production and other aspects of the PV market:
China owns the largest hub of panel manufacturing and has several solar farms. They are also known for the world’s largest floating farm that generates 40MW of electricity. Currently, China’s share in the manufacturing stages of solar panels such as polysilicon, ingots, wafers, cells and modules exceeds 80% and thus the country owns a share double the time of that of global PV demand. Since the country Homes world’s top 10 suppliers of solar PV manufacturing equipment, they have been working towards bringing the costs worldwide for solar PV.
The Chinese industrial policies and strategies focus on growing domestic demand and have supported continuous innovation throughout the supply chain. These effective policies have reduced the cost by over 80% and have helped solar PV electricity generation most affordable among sustainable energy solutions. However, some factors have created supply-demand imbalances in the PV supply chain and
Innovations and market trends:
Since 2022, ground-mounted solar PVs have dominated the industry with countries like China, the United States, Germany and India which is also leading the market growth. This is because of the declining costs of solar PV installations, solar energy targets and the growing rate of utility-scale projects. There are significant investments and agreements made for the development of photovoltaic power plants. Some of such incidents are:
- In May 2023, Savannah Energy Niger Solar Ltd., the British independent power company Savannah Energy Plc, had signed a memorandum of Agreement with the Niger government for the development of two solar photovoltaic power plants. These facilities are expected to have an installed power capacity of up to 200 MW. These projects are expected to receive sanctions next year and get into operational status in the next two to three years.
- China’s solar PV installed capacity has reached 392.436GW which is a 28.08% growth as of 2022 compared to the year 2021.
- The New Delhi government has approved the draft of the ambitious solar policy 2022 that revises the installed capacity of 6000MW from 2000MW in two years. In addition to that, the policy unifies the single-window state portal that is managed by the Delhi Solar Cell to provide information on the benefits of solar PV systems.
- Jinko Solar Holding Co. Ltd. Has improved its efficiency of N-type Top Con solar cells which helped it achieve a conversion efficiency of 25.4%. Likewise, they have expanded their manufacturing facilities to keep up with the growing demand for high-efficiency modules and they have been involved in large-scale solar projects across the globe.
- Overall there are several upcoming solar PV projects and supportive government policies, the situation combined with the declining costs of solar PV modules and associated systems. These factors contribute to the growth of the solar PV market.
Advancements continue…
The PV market is witnessing spurring innovations in chemical materials, higher efficiency and durability in PV cells. The companies are developing new semiconductor materials, coatings, and materials and striving to enhance the performance and lifespan of PV cells. Also, due to the incorporation of perovskite materials and new silicon-based compounds, the market is experiencing significant improvements in cell efficiency. Likewise, the advent of durable and weather-resistant encapsulants to protect PV cells from environmental damage and the innovation of polymers such as ethylene-vinyl acetate and other advanced encapsulants are attributing to the longevity and overall performance of solar panels. On the other hand, the push for green practices and sustainability is propelling the industry to adopt greener production processes and celebrating the less toxic solvents, materials recycling and reduction of waste in the manufacturing sector.
Other Important News Articles More