Innovation of Solar Energy: Sustainable, Colorless, and Transparent Solar Cells

Renewable energy is crucial for the present and the future since the ultimate objective of the sustainable energy system is to maintain our current needs without sacrificing the needs of future generations. In contrast to fossil fuels, which have a finite supply, solar energy is a renewable energy source that is sustainable. Solar energy is utilized to create electricity, heat indoor spaces, and heat household water. 

Although the solar sector is growing quickly to satisfy the world's energy needs, there are still a number of obstacles in its path. Traditional solar panels need a sizable setup area and have a significant initial cost. It is challenging to implement them in cities, especially in neighborhoods with lots of apartment buildings or shops, because of these restrictions. However, these obstacles may soon change as a result of recent innovations, such as transparent photovoltaic (TPV) in glazing products. 

Principle Operation of Transparent Solar Cells 

Transparent Solar Cells. Richard Lunt / Richard Lunt/Michigan State University

We may assume that a solar cell is a device that absorbs sunlight; however, a transparent solar cell’s goal will be defeated if the sunlight is totally absorbed (in the way that a glass window absorbs light). The transparent solar cell is designed such that visible light may flow through while it absorbs radiation from the invisible spectrum, such as infrared and ultraviolet rays (Figure. 1). 

Figure 1. Light Spectrum

While permitting regular visible light to flow through, the transparent solar cell selectively captures a section of the solar spectrum that is opaque to the human eye. The visible portion of the spectrum is shown to flow through the solar cell in Figure. 2. Infrared photons are what excite the electrons in the transparent solar cell. The visible spectrum is represented by VIS in this context. NIR stands for near-infrared light that the solar cell will absorb. 

Figure 1. Schematic Representation of Transparent Solar Cell. VIS stands for visible spectrum and NIR stands for near-infrared light.

Recent Developments  

In Glazing Products 

Using transparent photovoltaic (TPV), which goes beyond the capacity of producing power and enhances the thermal performance of the building, is one approach to increasing efficiency of solar energy. According to US Energy Information Administration, solar energy accounted for 3% of the nation's overall power production in 2020. In the United States, there are 5–6 billion square meters of glass surfaces. On the other hand, traditional glazing techniques of buildings are frequently ineffective insulators. 

Transparent solar photovoltaics are utilized for various kinds of windows, roofs, facades, etc. to lower the overall energy consumption of the complete structure. Additionally, they are capable of transmitting daylight, giving users the choice of enjoying natural illumination while generating power. About 40% of the US's total power will be produced by this area if it is used effectively with the aid of transparent photovoltaics. 

By utilizing this technology, buildings will transform into power plants that create enormous amounts of power daily. This is advantageous  because the energy produced is clean energy and electricity costs may be reduced. There are several businesses that are putting this technology in buildings, including Physee, Ubiquitious, and many more. 

Potential Applications  

In Devices Electronic 

Mobile phones, laptops, desktop computers, watches, clocks, and many more electrical devices may all employ transparent solar cells. This would be helpful because it would allow the battery to automatically recharge anywhere and at any time. The cells will also reduce the chance of the electronic device turning off. It will always have a minimal quantity of energy, which might be useful in an emergency. 

In Automobiles 

Translucent solar cells may be installed on cars and other vehicles as windows, sunroofs, and windshields. The energy produced can be used to power extraneous automotive components like the radio, headlights, fan, wipers, etc. As a result of having to carry fewer loads, this will lengthen the lifespan of an automobile's primary battery. When employed broadly, this technology has a wide range of uses. 

Despite all the potentials mentioned above, transparent solar cells haven't been widely utilized yet. However, this kind of technology can advance quickly, and the potential for fantastic outcomes is there. As this technology becomes more affordable, it will be employed worldwide to easily satisfy the demands of a large population