In 2022, the global photovoltaic (PV) solar market was valued at USD 259 billion and is anticipated to rise to USD 381 billion by 2027.
PV technology converts light into electricity and has been around for more than 75 years. Traditional systems use silicon to detect light and convert it into energy, but modern PV technology uses dye-sensitized solar cells (DSSCs).
DSSCs are comprised of a liquid electrolyte and a metal oxide semiconductor (MOS) that is sensitive to light. The light-sensitive MOS facilitates the transfer of electrical charges between photoreceptors (solar cells) and conductive materials such as metal grids or thin wires.
When light falls on a DSSC, the device will generate a slight electrical charge and display the potential to convert sunlight into electricity. However, before a DSSC can be used for practical purposes, several key performance metrics, such as power conversion efficiency (PCE) and short-circuit current (Isc), need to be optimized.
PCE, for short, measures the efficiency of a solar cell in converting sunlight into electricity. Calculated using the following formula:
- PCE = (I η / PI)
- I η is the total current (A) generated by the solar cell under standard testing conditions
- PI is the power (W) of the solar cell under standard testing conditions
- Short-circuit current (I sc) measures the amount of electricity, which travels through the cell under short circuit conditions (open circuit)
- The value of the short-circuit current (I sc) is usually between 0.5 – 1.5 amperes
- Ampers is the SI unit of electrical current, equal to the amount of current that flows through a circuit for one second
According to GTM Research, the global market for solar devices was valued at USD 259 billion in 2022 and is anticipated to rise to USD 381 billion by 2027.
Solar devices are used to generate electricity for various applications such as power supply for homes and other buildings, rural electrification, and industrial uses.
This growth is attributed to the increased demand for green energy solutions due to sustainability concerns and the desire to reduce dependence on fossil fuels. In terms of cost, the global market for solar devices is anticipated to decline by 6% year from 2022 to 2027.
In late March 2022, the Sunstone Global PV Summit recognized the U.S. company, SunPower, with the award for Breakthrough Engineer of the Year for its innovative, high-efficiency, thin-film PV technology.
The technology was developed in collaboration with the Massachusetts Institute of Technology, and it records the highest PCE among all types of PV cells. SunPower’s technology combines a perovskite-based film with an atomic layer deposition (ALD) TiO2 film to form a tandem structure. This is combined with a silicon PIN junction and an N-type GaN junction to create a hybrid PV cell.
According to the company, the technology offers the efficiency of a crystalline silicon solar cell with the price and resource economy of an organic solar cell.
PCE Greater Than 20%
In mid-February 2022, Chinese manufacturer, JinkoSolar, announced that its PV cell, JS 330, had reached a PCE of 20.9%. This effectively doubles the efficiency of the company’s previous generation PV cell, JS 316.
The new generation also outperforms the efficiency of any previous thin-film solar cell developed using an organic compound, such as poly(3-hexylthiophene), or a derivative of Silicon, such as Silicon Carbide or Silicon Germanium.
In terms of price per watt, the JS 330 cost USD 0.15/W and the JS 316 cost USD 0.10/W. These prices are comparable to the cost of electricity from solar photovoltaic power stations currently in operation worldwide.
The announcement represents a significant improvement in the cost-effectiveness of solar energy, and it is expected that the industry-standard PCE of 20% will be more affordable in the near future.
PCE Decreases As Cells Age
In late January 2022, the U.S. company, SunPower, reported that the average efficiency of their PV modules had decreased by 1% year after year for the last five years.
To compensate for this decrease in efficiency due to age, the company suggests that their customers use additional cells or modules to form an array.
Using three years of data from their customers, SunPower was able to determine that this decrease in efficiency was mainly attributed to an increase in the number of dark spots on the solar cells as they aged. As these spots accumulate, they will decrease the efficiency of the entire module and, ultimately, the whole system.
This is a significant issue because, as the world’s foremost experts agree: solar cell efficiency declines significantly year after year, even after accounting for degradation, unless the cells are regularly replaced.
In early 2022, the U.S. company, SunPower, also reported that they had set a new record for the short-circuit current of their PV cell, JS 330. The new generation of solar cells achieved a maximum power output of 24.96 W, which is greater than double the previous record of 11.6 W set in 2018 by the company.
The new record setting also represented an increase of 16% year-over-year. In terms of price per watt, the JS 330 cost USD 0.15/W and the JS 316 cost USD 0.10/W. These prices are comparable to the cost of electricity from solar photovoltaic power stations currently in operation worldwide.
The new technology combines a perovskite-based film with an atomic layer deposition (ALD) TiO2 film to form a tandem structure. This is combined with a silicon PIN junction and an N-type GaN junction to create a hybrid PV cell.
SunPower’s head of business development, Jameela Najjar, suggested that this was mainly caused by an increase in the efficiency of their manufacturing process and the introduction of new materials which enabled them to harness greater amounts of sunlight than before.
New Business Models
To remain profitable in the long term, the solar industry will need to embrace business models that are different from traditional sales. This means that companies will need to rely less on buying high-priced solar equipment and more on using their resources, such as employees or intellectual property, to sell solar products and services to other businesses or individuals.
For example, in 2021, the California-based company, Sunify, which provides system integration and project development for solar power plants, launched the world’s first community-based solar power plant. The plant, which is located in Oakland, California, provides electricity to roughly 20% of the city’s residents and reduces the community’s dependence on fossil fuels.
According to the company, the community aspect enables residents to participate in the operation of the plant and have a direct impact on the products which they use. Additionally, Sunify’s project management team works with local residents to ensure that the plant operates at its optimal capacity and reduces harmful emissions. In future, similar projects aim to provide electricity to more people and reduce their dependence on fossil fuels.
In 2021 and 2022, the global markets for solar equipment and solar cell manufacturing were valued at USD 259 and 381 billion, respectively. It is anticipated that the solar market may decline by 6% in 2027 due to a decrease in the price of solar equipment and shortage of trained professionals in the sector. However, the overall demand for clean energy technologies will more than make up for this decrease.