Many solar-powered companies manufacture technology that powers a greater and
greater variety of objects. However, often, the cost of solar is a deterrent to consumers. The
myriad of smaller companies, because of the high costs of doing business, tend to be unable to
produce enough power cheaply enough for the common consumer. But if these smaller
companies teamed up to make one grand solar-powered technology, it would be much more
efficient and would be able to power much more with less sunlight, and less cost. The sun gives
off so much energy in its rays already, that if it could be fully harnessed, it would power
everything on earth several times over. According to Energy.gov, “The amount of sunlight that
strikes the earth's surface in an hour and a half is enough to handle the entire world's energy
consumption for a full year” (How Does Solar Energy Work, 2017). The idea of doing this is not
totally out of reach. In China, in the year 2017 alone, they increased their solar photovoltaic
panels (PV) capacity by 60 gigawatts. On their own, little solar companies do not have the
capacity to make significant changes to solar technology that would majorly increase the
efficiency. But together, they could better and more efficiently harness more power through
better technology with greater efficiency and lower cost.
Upgrading solar technology so that it harnesses more power, more efficiently, is not a
small order. Some of the reasons for this are that PV panels rely on semiconducting silicon to
take in sunlight and convert it to electricity. Though the amount of sunlight that these crystals
convert to electricity is only about 15-19% of the overall intake. This initial discovery of solar
power, unbeknownst to many in the industry at the time, took several decades just to complete. If
scientists were able to team up rather than work apart, their discoveries would certainly be
produced faster and more steadily. “In an abundance of counselors, there is wisdom.” And this
applies to the sciences in the same way. In an abundance of scientists (whose goals are one),
there is much discovery and innovation.
Whether innovating technology to make greater solar gains or just implementing more
solar photovoltaic technology for increases, more materials, mainly silicon, are essential. The
Paris Climate Agreement’s 20-year goal is to power 30% of the world using strictly solar power.
If people were able to make a new, better technology that converted more of the sun’s power to
electricity, there would be much less need to make a lot more solar PV because much more
energy would already be inflowing.
In order to achieve the Paris Climate Agreement’s 20-year goal, more solar PV will either
need to be implemented or improved. The current solar PV technology has a very complex
process and may be hard to update. According to Stephen Forrest, in general, solar PV has a
layer of semiconductor material that absorbs the sun’s light. This process generates electrons and
“holes”, which are just vacancies where electrons usually are located. The electrons then flow
around the circuit working and filling these holes. A silicon layer is also needed, in order to
absorb a good portion of the light; the silicon layer must be 200 micrometers or higher. Though
silicon is a good material for solar PV, there are other materials that absorb much more sunlight.
However, these materials are found in less quantity, and are more difficult to mine and gather.
Cadmium Telluride, and Copper Indium are a few materials that have been shown to
absorb and convert sunlight thoroughly. Siser says “CdTe thin film solar cells are becoming
increasingly popular within commercial photovoltaic production due to their low fabrication cost
and rising efficiency” (Cadmium Telluride, 2019). These materials share about 5% of all solar
PV technology, and have been shown to match silicon in efficiency and cost. While these
materials represent a significant technological upgrade, there are several geopolitical obstacles to
mining the necessary minerals. Consequently, scientists have been researching organic
alternatives.
Organic cells have many things that inorganic cells lack. EnergySage says “Scientists are
always looking for ways to make solar as efficient, accessible, and aesthetically pleasing as
possible. Some of the most exciting research and development taking place in the industry today
revolves around constructing thin, flexible solar options using organic solar cells” (Marsh, 2021).
For example, organic cells are flexible and malleable which allows for easier installation on
buildings’ roofs. Organic materials are also able to reproduce and can be designed to absorb
infrared light, while staying transparent in visible light. This means that organic cells could be
put into windows without disrupting the window’s transparency. One window with PV cells
demonstrated 7% efficiency while allowing 43% of visible light pass through the window. While
43% of visible light passing through a window is not ideal, the increased energy efficiency
would generate significantly more power. Further, placing organic cells inside a window would
protect it from oxidation, effectively preserving the life of the cell.
One consideration, when weighing the implementation of a new technology, is
determining if the benefits outweigh the sum of the costs; materials, installation, and recycling.
In this way, economists would be involved in addition to scientists. They must consider whether
materials are too pricey and difficult to find; whether installation is as feasible with these
materials as with others and what the cost is of the structure in addition to the labor; and finally,
if these materials can be more cost-effective through recycling and renewing their usefulness.
Scientists are working to improve two aspects of organic cells: the lifetime of organic
solar panels and their efficiency. Scientists believe that the best organic cells for solar PV are
perovskites. Perovskites are used for many different things and can produce many other
materials. One of the materials, methylammonium lead halides, was recorded to capture 23% of
the sunlight. One of the reasons that perovskites are so efficient is that there are very little defects
in the crystal structure, so very few electrons and holes are lost. However, there are also
disadvantages to using perovskites. Perovskites include toxic lead, and tend to degrade when
exposed to liquids. While perovskites can be wrapped in plastic to prevent degradation, the
problem of lead remains. Another problem that all materials face is that when the photon hits the
electron, if it has enough energy it can convert the electron into a charge carrier. But if it does
not have enough energy, the photon is wasted, but if it has too much energy above the gap, the
energy is wasted. This is one of the main problems with all materials, but, in an attempt to rectify
this situation, scientists combined perovskites and silicon together, and the predicted efficiency
limit is 43%. However, when attempted by the Oxford Photovoltaics company, the actual
efficiency limit was 27.3%. The two materials stick together by making an electrical conductive
adhesive. They believe future versions of this will have a 25 to 26% efficiency limit, and if they
stack them together they believe that the efficiency will be as high as 37%.
In addition to these technologies, novel optics would render more power from the sun.
This is because it would provide better antireflection coating which would allow more sunlight to
enter. Novel optics also restrict the emission of radiation when electrons and holes combine. In
effect, novel optics uses nano cylinder technology to supercharge solar cells. Nano cylinders are
made of an insulating material instead of a semiconductor, the result of this is that certain
wavelengths bounce off while others are transmitted. Polman’s group is working on a reflector
that will boost the performance of these perovskite-silicon cells, and if they are successful may
even be able to achieve a new, better solar technology.
The current solar PV utilizes silicon, which does not take that much energy from sunlight.
Organic materials, an alternative to silicon, such as Cadmium Telluride and Copper Indium are
more effective but not as effective as perovskites. Perovskites are very efficient but have some
downfalls such as lead. Because of this, another solution is to mix silicone with perovskites and
create novel optics as a new solar technology. These are just a few of the ways that separate and
small solar tech companies can achieve greater solar efficiency. All in all, many companies have
come up with ideas that, if combined, would most likely produce a new technology that would
provide more efficient power.
Works Cited
Battersby, S. (2019, January 2). News feature: The Solar Cell of the future. Proceedings of the
National Academy of Sciences of the United States of America. Retrieved April 21,
2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6320527/
How does solar work? Energy.gov. (2021). Retrieved April 21, 2022, from
https://www.energy.gov/eere/solar/how-does-solar-work
User, S. (2019). Cadmium telluride (CdTe) and copper indium gallium selenide (CIGS) solar
cells. SISER. Retrieved April 24, 2022, from
https://www.siser.ac.uk/research/thin-film/cadmium-telluride-cdte-and-copper-indium-
gal
\lium-selenide-cigs-solar-cells
Marsh, J. (2021, June 11). Organic Solar Cells: What you need to know: Energysage.
EnergySage Blog. Retrieved April 24, 2022, from
https://news.energysage.com/organic-solar-cells-what-you-need-to-know/
