Session C4
109
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TANDEM PEROVSKITE SOLAR CELLS:
IMPROVING THE CAPABILITIES OF SOLAR PANELS
Sydney Winner, [email protected], Sanchez 5:00, Olivia Yasser, [email protected], Sanchez 5:00
Abstract—As a society we are currently reliant on nonrenewable and unsustainable energy sources; however,
recent developments in solar technology may make it a strong
competitor as a sustainable energy source. Through the use
of perovskite structures layered in tandem within solar cells,
solar energy may be more efficient than it has ever been
before. While still in the research phase, lab results of tandem
perovskite solar cells are continuously improving. In fact,
recent studies have shown that perovskite is the most efficient
solar cell in current lab research, far beyond the efficiency of
any other current photovoltaic technology. Perovskite is a
unique molecular structure that, in the case of solar cells,
allows photons to pass through their structure creating
voltage that can be harnessed. We will address the
advantages of perovskite solar cells in tandem and also
explore the ethical dilemmas the use of this technology
presents. We intend to show how the advantages of perovskite
in both sustainability and cost efficiency far outweigh any
disadvantages this technology may pose. Perovskite solar
cells in tandem are a technology that could revolutionize
solar energy as we know it.
Key Words— Lead in Perovskite, Perovskite, Perovskite
Solar Cell Efficiency, Perovskite Solar Cell Cost Effectivity,
Perovskite Solar Cells in Tandem
INNOVATING SOLAR ENERGY
The growing need for sustainable energy has become an
undeniable fact in modern society. In 2015, only 10% of the
energy used by the United states was renewable and of that
10% only 6% was comprised of solar energy [1]. With the sun
continuously cycling over our planet every day, why do we
leave so much energy to go to waste? A large factor is that
currently manufactured solar panels do not have high enough
efficiency or cost-effectiveness to make them a smart
purchase for the consumer. For many years, it seemed as
though there was nothing to be done to improve the efficiency
of solar cells, especially with the efficiency of the widelyused silicon asymptoting at 25.6% in laboratory research [2].
Thankfully a new, expeditiously improving technology has
come to the forefront of solar research: perovskite solar cells
layered in tandem. Perovskite solar cells offer the unique
University of Pittsburgh Swanson School of Engineering 1
02.03.2017
advantage of being both cheaper to produce and more
efficient as a photovoltaic technology. When layered in
tandem, perovskite has the potential to deliver efficiencies far
above any photovoltaic technology we have seen before.
Throughout our paper, we will outline the science behind the
technology to better explain the potential benefits of
perovskite solar cells layered in tandem for the future of solar
technology. Furthermore, we will explore solar technology as
a more sustainable source of energy for the future.
CURRENT SOLAR CELLS
Molecular Structure of Silicon Solar Cells
Crystalline silicon solar cells are the most common solar
cells used in commercially available solar panels today,
mainly due to their reliability and stability. Silicon is an atom
that has the ability to share four of its valence electrons. This
is useful for crystalline silicon solar cells because the silicon
atoms are arranged in such a way that each silicon molecule
connects with four other silicon atoms around it. This
structure creates such a pure material that only .0001% of the
atom is not silicon [3]. Unfortunately, crystallized silicon
cells that are this pure are poor absorbers of light and can be
dense and rigid. Because of this, manufacturers put silicon
structures through a process called doping. In this process,
semiconductors, in our case silicon, are doped to modulate
their electrical properties. This allows researchers to separate
electrons from the hole formed by the photon entering the
solar cell. Furthermore, this also allows researchers to
measure the amount of electricity the solar panel produces. In
the doping process, dopants are used to produce the desired
electrical characteristics in semiconductors, in this case, solar
cells. For silicon cells, the typical dopants used are boron (ptype), which is neutrally charged, and phosphorus (n-type),
which is positively charged. These impurities are put onto the
silicon structures, which have different numbers of valence
electrons. In Figure 1, it can be seen how the top of the cell is
doped with boron and the other cells are doped with
phosphorus, resulting in the ability to harness more light [3].
Sydney Winner
Olivia Yasser
photons. In order to obtain electricity from the light rays
coming into the solar panels, photons go into the cell and
bounce into the valence electrons that are present from the ptype and n-type semiconductors. Valence electrons are
present in the outermost orbit of the electron cloud that
surrounds an atom. Because they are so far from the positive
nucleus at the core of the atom, there is less attraction between
the valence electrons and the core than there is between the
inner electrons and the core. Therefore, only a small amount
of energy is needed for the electron to separate from the atom
and travel freely throughout the solar cell. Once the electron
is removed, a hole is left behind. This causes the electric field
to be pulled toward the p-type semiconductor, while the hole
is pulled toward the n-type semiconductor. This forces all the
free electrons that were let loose from the photon to move to
one side of the cell. Ultimately, this forms the electric current
necessary to produce a valid source of electricity in the solar
panel [4].
To further complicate this process, not all photons create
a hole when the electron is set loose. Only electrons that have
enough energy to knock an electron out of its place can form
the hole in the solar cell. Each photon in the light waves that
hit the solar panels carry a specific amount of energy in
electronvolts (eV). To knock an electron out of the electron
cloud around a silicon atom, it takes 1.1 eV. This is called a
bandgap, which requires a different amount of energy for
every type of solar cell. [4]. The process of how the band gap
is formed when the photon moves out an electron is shown in
figure 2. An understanding of band gaps is also essential in
understanding perovskite tandem structures.
FIGURE 1 [4]
This shows how molecular impurities are formed
through the doping process.
After both the n-type semiconductors and the p-type
semiconductors come in contact, the free electrons from the
n-type semiconductors jump across the junction between
them and fill the open spots on the p-type semiconductors.
The p-type now becomes a negatively charged region because
it is full the electrons from the n-type semiconductors and the
n-type now becomes a positively charged region after losing
its electrons. In between these two regions becomes a
depleted region because it is neutral of charge, this is where
the electrical field is formed. If an electron is stuck in the
depleted region, it is pulled towards the positive side [3].
PEROVSKITE SOLAR CELLS
Perovskite as a Mineral
Perovskite is an organic-inorganic mineral that is
composed of a combination of class materials with similar
structures. The original form of perovskite was calcium
titanium oxide (CaTiO3), the name has generalized to a whole
class of materials with the same crystallized structure. The
structure of the perovskite mineral is what gives the basis to
the structure of perovskite solar cells. It is perovskite’s unique
structure, size, and efficiency rates that make it outshine other
developing technologies, such as polymer and dye-sensitized
solar cells. A typical perovskite structure takes the form of
ABX3, in which A and B are cations (positively charged
molecules) and X is an anion (negatively charged molecule),
in which A is larger than B [5]. The typical structure of
perovskite generally has a cubic structure, which gives it a
more stable and strong outer structure. It is created by placing
the A molecule at the center, the B molecule at the corners of
the cube, and the X molecules at the center of each side of the
sub. This can be seen in Figure 3 [6].
FIGURE 2 [4]
This shows how a band gap is formed when light photons
enter the solar cell.
However, this does not allow the crystallized silicon
solar cell to produce electricity from the incoming light
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perovskite is 1.54 eV with the valence band (VB) at -5.4 eV
and the CB at -3.9 eV.” [6]. As depicted by Figure 4, the
valence band and combination band are both in line with each
other in this perovskite structure which indicates that
perovskite has a direct band gap. This means that all of the
photons harnessed by perovskite can go directly into
producing energy. If the bandgap was indirect, as depicted on
the right-hand side of Figure 4 below, then energy that could
be harnessed from the photons would be lost as phonons and
heat.
FIGURE 4 [6]
This shows the difference between a direct (left) and
indirect (right) bandgap in harnessing photons.
FIGURE 3 [6]
This shows the 2D and 3D models of the perovskite
structure. The purple molecule is the A element, the
black/blue is the B element, and the yellow is the X atom.
Researchers at the Moscow Engineering Physics
Institute recently worked on optimizing the relationship
between efficiency and thickness of solar cell. The research
found that efficiency and thickness were directly linked by
perovskite’s band gap [6]. This optimization utilized a drift
diffusion approximation based on the Possion equation, a
partial differential equation that is able to be interpreted for
many engineering purposes. It also related the properties of
perovskite as a photovoltaic to properties of superconductors.
Through these methods, it was determined that the optimal
thickness for a perovskite solar cells was between 500-600
nanometers [8]. This determination is important to note
because it is a relatively small number that lends perovskite
its flexibility. The advantages of this flexibility are especially
notable in the comparison between silicon and perovskite
solar cells.
In an organic-inorganic perovskite structure, the A
compound typically consists of from a small monovalent
(having only one valence electron) organic cation. Typical
examples are methylammonium or formamidinium. The
element B is always an inorganic cation from the Group 14
metals on the periodic table, such as lead (Pb), Tin (SN), or
Germanium (Ge). Finally, the X element is a slightly smaller
halogen anion, usually chloride (Cl-) or iodide (I-). Since a
variety of atoms and molecules can be used to create the
perovskite structure, the stability and properties of these solar
cells are heavily dependent on what type of molecules are
used. The way the electrons and molecules are aligned in its
structure gives perovskite an array of properties including
superconductivity and magnetoresistance [7]. The perovskite
structure is extremely beneficial for use in solar cells because
it maximizes the way energy is transferred and how electrons
can jump across the energy gap.
PEROVSKITE IN TANDEM
While perovskite shows great potential for increased
efficiency, the next big leap in solar cell capabilities will come
from layering perovskite in tandem with small band gap solar
cells. A tandem solar cell involves layering two solar cells on
top of each other in various architectures in order to harness
more energy and maximize efficiency. The ability to harness
more energy is granted through the integration of a large band
gap solar cell and a small band gap solar cell. The difference
in the band gap size allows the different parts of the tandem
cell to harness photons of different energy levels. This is
achieved without losing energy due to heat and phonons as
Perovskite Solar Cells
Perovskite is particularly advantageous for its use within
a solar cell. This is due to the relative simplicity of the
structure while maintaining a high ability to convert light to
energy. In research done on perovskite by Dr. Prasenjit Kar at
the Indian Institute of Technology, it was found that, “the
direct band gap of the methylammonium lead iodide
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described earlier because the bandgap is not misaligned with
the energy levels. The tandem cells catch energy similar to
two strainers of different fineness catching items of different
sizes based on their straining holes. This allows for a greater
number of harnessed photons and higher efficiency. A single
junction solar cell is modeled to have an ideal efficiency of
33.7% while a tandem perovskite solar cell is modeled to have
an ideal efficiency of 46.1% [2]. Figure 5 depicts both a single
junction cell and a double junction cell. The figure illustrates
the ability of the double junction cell to harness more energy
because it harnesses the different energy level photons in
different steps, allowing for the creation of both high and low
voltage, instead of just low voltage in the single junction cell.
Each architecture offers its own unique advantages.
Mechanically stacked tandem architectures are currently the
most practical to implement. The mechanical stacking process
involves fabricating the top and bottom cells
independently. The two cells are then assembled together
into one solar cell. This is advantageous because it allows
single junction solar cells to have a layer of perovskite added
to it in order to create a tandem cell and boost their individual
efficiencies [2]. The compatibility of the voltage limits this
process. The perovskite cells to be layered in tandem can be
engineered to match the current or voltage in the already
existing cells allowing for smooth integration. Mechanically
stacked tandem architectures are also advantageous because
they allow for the separate binning of the tandem sub cells.
Binning is a process of testing solar cells for a specific
power class, or amount of wattage they are able to produce
[9]. Since manufacturing processes aren’t always precise, a
few different power classes of solar cells can come from the
same production line. By sorting the solar cells through
binning, manufacturers can align perovskite solar cells with
manufactured solar cells of the same bin and therefore the
same voltage. This allows for the smoother integration of the
large and small bandgap solar cells and ultimately higher
efficiency [2].
Monolithically stacked tandem solar cells promise
higher efficiency potential than even mechanically stacked
tandem solar cells, but require major adjustments to solar cell
manufacturing facilities [2]. Spectral splitting combines the
idea of both mechanically stacked tandem and monolithically
stacked tandem solar cells by integrating a small bandgap
bottom cell (as pictured in Figure 6) with a perovskite top cell
perpendicular to the small bandgap bottom cell. Bisecting
these two layers is a dichroic mirror allowing the highest
theoretical efficiency of all three tandem solar cells while also
creating the least practical manufacturing system [2]. Due to
the impracticalities of spectrally split solar cells, we will
center our focus around the application of mechanically
stacked and monolithically stacked tandem architectures.
FIGURE 5 [2]
This shows the ability of a tandem structure to capture
more energy through having two layers.
Tandem Architectures
The way that a tandem cell is structured can greatly
affect both its efficiency and its manufacturing process. There
are three main tandem architectures: mechanically stacked
(Figure 6 a), monolithically integrated (Figure 6 b), and
spectrally split (Figure 6 c).
Perovskite in Tandem with Silicon
Mechanically stacked perovskite tandem architectures
offer an interesting prospect for future solar cell
manufacturing. Perovskite could theoretically be layered in
tandem with any small bandgap solar cell. This leads to the
interesting prospect of perovskite on perovskite solar cells
through the use of the theoretical small bandgap perovskite
solar cell [2]. However, since this technology is not
thoroughly researched, we will investigate other prospects of
perovskite in tandem, specifically perovskite layered in
tandem with silicon. Due to the nature of the mechanically
stacked tandem architecture (i.e. the separate manufacturing
of the top and bottom solar cell layers) there is a very real
potential to modify currently existing silicon solar cell
FIGURE 6 [2]
This shows the three different types of tandem
architectures mechanically stacked (left), monolithically
stacked (center), and spectrally split (right).
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manufacturing plants to create perovskite silicon tandem
structures with relative ease. These perovskite silicon tandem
structures would have higher efficiencies than technology
currently in the market. A theoretical modeling of perovskitesilicon tandem structures using AFORS HET computer
simulation was conducted at Sungkyunkwan University in
Korea [10]. This modeling showed an improvement of
efficiency by a factor of 1.39 compared to single junction
perovskite and 1.59 compared to single junction silicon [10].
The overall modeled efficiency of the tandem cell was
24.92%. This model was conducted without accounting for
the use of surface texture, a very common process to improve
the efficiency of solar cells [10]. This means that with the use
of additional solar cell technology, like surface texture, higher
efficiencies could be achieved then the one modeled even up
to 46.1% as predicted by researchers at Stanford University
[2].
Another modeling of perovskite, which was published
in IEEE’s Photovoltaic Specialist’s Conference looked at the
factor that could cause a reduction in efficiency in the realworld implementation of perovskite silicon tandem solar cells
when monolithically stacked. The study found that
temperature, spectral irradiance distribution, and angle of
incidence are the largest factors in the efficiency reduction in
the real-world application of tandem solar cells. However,
these factors only reduced the energy yield, or energy
produced by the solar cell, by 4.5% [11]. With further
technological innovations, the effect of real world factors on
efficiency, and consequently energy yield, could be reduced.
However, this study shows that while real-world factors may
affect the operation of perovskite silicon tandem solar cells, it
is not completely detrimental to their application. This would
allow for real-world implementation of perovskite silicon
tandem solar cells to begin in the near future, manufacturers
allowing.
chemical reaction with water. This leads to major degradation
problems, including breaking down the bonds in the
perovskite’s structure. As a result of these issues, perovskite
researchers have found that perovskite devices may require
thicker light-harvesting layers that would shelter the
molecules from UV lights and moisture [5]. While adding a
thicker layer would provide protection for the molecules, this
would require more changes in the manufacturing facilities
and would likely increase the cost of production.
The Use of Lead
In the ABX3 structure, the B element can have multiple
Group IV elements in the divalent oxidation state; however,
as the atomic number of these elements decreases, the
stability of the structure decreases. As explained earlier, there
a multitude of molecules that can be used as the B element.
Among these, Pb is the most beneficial to perovskite’s
stability because it has the highest atomic number in the
Group IV elements of the periodic table. Research has shown
that the best solar performances come from molecules with
higher atomic number because their radius is the largest and
it takes less energy for photons to create band gaps when the
solar cells absorb light.
Although lead is one of the many solutions to
perovskite’s structural stability, it causes major concern for
potential environmental issues. Exposure to lead can cause
detrimental health problems ranging from reproductive
damage to cardiovascular issues to developmental diseases
neurologically. For reasons such as these, lead was reduced in
everyday objects and its concentration in society was brought
down dramatically.
The presence of lead in perovskite devices can be as
damaging as lead being present in water pipes. Solar panels
are built to withstand most degradation and decomposition;
however, when exposed to precipitation lead could seep out
into its surroundings. As explained by the Journal of Physical
Chemistry, when a typical perovskite composition comes in
contact with water, decomposition takes place. For instance,
if methylammonium lead iodide is reacted with water, it
decomposes to a simpler molecule and leaves lead iodide
behind. When this compound is left behind it can be
dangerous because the remnants of lead could find its way
into the liquid waste of the solar panels and spread toxins into
its surrounding area [13]. With lead being present in
perovskite, there are many risk factors to the environment and
the areas surrounding the solar panels.
Although this is a setback to the development of
perovskite devices, researchers have come up with some
solutions that may better perovskites effect on the
environment. The production of lead from raw ores can
produce toxic residue and spread harmful chemicals into the
environment [13]. However, using recycled lead from old car
batteries can divert toxic materials from being spread. A
ETHICAL DILEMMA
Lifespan and Stability
As with many new developing technologies, there are
some ethical dilemmas that are casting a shadow over the
development of perovskite solar cells. In perovskite’s current
stage of research the only major unknown is the stability and
lifetime of the devices as they operate. Research studies have
shown that the devices exhibit specific degradation
mechanisms and sensitivity to heating, UV illumination, and
moisture [12]. During UV exposure, the light absorption of
perovskite devices start to decrease because the individual
materials that make up perovskite start to lose some of their
abilities, such as conductivity, after 200 hours of UV
exposure. This would affect perovskites long term ability to
be efficient. Moreover, when perovskite is exposed to
moisture, the chemicals in its structure tend to hydrolyze.
Hydrolyzing is the chemical breakdown of a compound by a
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research team from MIT has been studying the effects of using
old batteries in perovskite technology [14]. The team’s
analysis shows that by using a single old car battery, it could
fuel enough solar panels to provide for 30 households [14].
Moreover, the way the battery would be layered into the solar
cells would protect it from precipitation that would leak lead
into the surrounding areas [14]. These solutions greatly
reduce the risk of using lead in the solar cells.
Another solution that is currently being researched is
using tin as a replacement for lead. Most of the current studies
on solar cells are based on lead perovskite materials because,
as of now, they are the most efficient way to convert sunlight
directly into lead. For the first time, researcher at
Northwestern University just successfully employed a tinbased perovskite that would provide a low-cost,
environmentally friendly, and comparably efficient solar cell.
The only setback with this solution is how it might change the
overall stability of the perovskite structure [15]. Hopefully
upon further research, this may be a viable option in the
future.
solar cells on the market. This shows a good outlook for a
future of clean and renewable energy.
Cost of Production
Currently, the production of crystallized silicon solar
cells is a long and complex process. Silicon is such a pure
molecule that when manufactured into a crystallized structure
for solar cells, needs to go through a doping process to create
imperfections. This allows for photons to create band gaps
when the light is absorbed through solar panels. Furthermore,
traditional solar cells require high temperatures to purify their
silicon bases during the doping process. This additional
requirement is both costly and time consuming which largely
decreases the value of using silicon-based solar cells in solar
panels [16].
However, the production of perovskite is quite the
opposite of the silicon solar cells. To create a perovskite solar
cell, it is a simple and short process. MIT News details
perovskite’s ability to be blended at a lower temperature,
which allows manufacturers of perovskite to cut out the costs
of heating silicon. Furthermore, since perovskite solar cells
are not composed of pure materials, they do not require the
same doping processes that traditional solar cells need. There
are already many imperfections within perovskite structures
that allow for a shorter and less costly doping process [14].
Perovskite’s ability to be blended at lower temperatures and
the fact that is does not need to be doped removes many of the
production costs associated with solar cells. The production
of perovskite would be financially beneficial to the
manufacturers of solar panels.
COST & EFFICIENCY
Efficiency
When perovskite was initially discovered and put into
solar cells in 2008, it had a mere efficiency rate of just 3.8%.
At this time, there had not been enough research on perovskite
and it had not been engineered using the molecules it needed
to give it a proper structure to capture sunlight and convert it
to energy. By the time it was introduced to the market in 2012,
it had a small, yet increased efficiency of 10%. This was
surprisingly high for the minimal amount of engineering and
research perovskite had, especially considering that many
other materials tested for use in solar cells leveled off at an
average solar energy capture efficiency of 14%. Most notably,
however, was, at the beginning of this year when perovskite
solar cells jumped to an extremely high performance
efficiency of 22%, which matches the performance of current
silicon cells [16].
Due to this sudden spike of efficiency from perovskite
solar cells, the interest in research in sustainable energy has
greatly increased. Many research laboratories and technology
developers have started to shift their interests from renewable
energy, to cost effective sustainable energy. This shows a
good future for developments of new sustainable energy
research and technology. Furthermore, many scientists have
“even suggested that a layer of perovskite with silicon could
lead to an un-imagined 44% efficiency as early as 2017. Even
a double-stack, layering perovskite on top of each other could
increase the efficiency to 30%, without the need to combine
it with other materials already in existence” [16]. This has a
significant impact on the future of sustainable energy. These
prospective numbers are almost unheard of with the current
SUSTAINABLILITY
Fossil Fuels
Nonrenewable energy sources, such as fossil fuels, are
overall the primary source of energy in the world. In the
United States, fossil fuels make up 81.5% of the energy
consumption [17]. However, there is a finite amount of fossil
fuels available for use in energy production. At the current
rate of discovery and usage of fossil fuels, it is predicted the
world will run out of available fossil fuels in the next 100 to
200 years [18]. Due to this fact, our current usage of fossil
fuels for energy is not sustainable. Additionally, due to the
increase in demand and usage of fossil fuels, there has been a
worldwide increase in carbon dioxide emissions. As detailed
in a Forbes article, “carbon dioxide emissions in 2015 were
36 million metric tons higher than in 2014, and marked the
6th straight year a new record high has been set” [19]. This
increase in carbon dioxide emissions shows that fossil fuels
are unsustainable due to their environmental impact. Carbon
dioxide emissions are harmful to the environment because
they trap additional solar energy in the atmosphere, leading to
adverse effects. These effects include shrinking water
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supplies, an increase in severe weather, changes in food
supply, and geographical changes [20]. All of these changes
lead to damage in our natural environment. In turn, the
resources we rely on from our planet become less sustainable.
Even more alarmingly, some of these changes have direct and
impending impacts on the sustainability of human life. As
reported by the environmental protection agency, “in many
areas, climate change is likely to increase water demand while
shrinking water supplies” [21]. This could have a huge
impact on farming and manufacturing as well as on supplying
water to the general public. Due to these complications, fossil
fuels are not sustainable in both a long-term usage and from
an environmental impact perspective. The best chance we
have at a long-term sustainable resource is renewable energy.
We will examine the particular sustainability advantages of
solar technology.
As compared to fossil fuels, solar energy is more
environmentally friend source of energy. Our traditional
source of energy, fossil fuels, are the leading contributor to
decreased air quality because they release carbon dioxide and
methane emissions. Comparatively, solar cells release no
harmful gasses into the atmosphere. The current amount of
solar technologies currently installed in the United States is
expected to offset about 16.8 million metric tons of carbon
dioxide that would have been produced from the use of fossil
fuels [23]. Furthermore, solar panels are more
environmentally friendly toward water sources. Typical
power plants, natural gas or coal facilities, require water to
cool down their facilities. With the use of solar energy, there
is no need for water to be used and, therefore, no water
pollution [23]. Solar technologies are both more cost effective
and environmentally friendly than traditional energy sources.
Because of this, they are more beneficial for society and are
more sustainable. However, the sustainability of solar panels
will always need to be further developed and it can further
improved when perovskite technology is added into the solar
cell. As detailed throughout this paper, perovskite tandem
technology in solar cells is both more cost efficient and
harnesses more energy. With the potential addition of
perovskite to mainstream solar panel technology, solar energy
will only become more sustainable both in longevity and for
the environment.
Solar Technology
As can be seen throughout this paper, the use of solar
energy has been increasing throughout the years. This solar
energy transformation is happening due to the economic
advantages of solar technology and the positive impact it has
on the environment. This makes these technologies more
sustainable and appealing to society. At the end of 2016, solar
panels were deemed to be the cheapest form of electricity. The
Solar Investment Tax Credit has shown that in the last decade,
solar power installations have experienced a growth rate of
60% [22]. Moreover, the cost to install solar technologies has
dropped over 60% in the last decade. As seen in figure 7, the
cost of installing solar technology is dropping as the
installations of solar technology is increasing [22]. This cost
improvement has led to the solar industry expanding into new
markets and research companies to advance solar
technologies, which makes it more sustainable and beneficial
for society. For example, more research has been funneled
into perovskite development because of the expanding solar
industry.
PEROVSKITE SOLAR CELLS FOR A
RENEWABLE FUTURE
Perovskite solar cells have the potential to create a
breakthrough in the solar energy industry through their simple
manufacturing process, low cost production, and their ability
to be layered in tandem to improve the efficiencies of preexisting small band gap photovoltaics. As the unique
perovskite structure creates a large band gap for harnessing
more photons, perovskite is one of the most efficient solar
cells being researched and its efficiency is only climbing with
each new development. The spark of research in photovoltaic
technologies due to perovskite creates hope for the field of
sustainable engineering in general. With more bright minds
working on perovskite solar cells, it becomes more and more
likely that the breakthrough necessary to get perovskite to
mass manufacturing will be achieved. Through investing in
and implementing the use of perovskite solar cells layered in
tandem in future solar technology, solar has the potential to
become more affordable and efficient. Solar energy is a
source of energy that is sustainable in both availability and
environmentalism. These benefits have created a sustainable
energy source that could rival the unsustainable fossil fuels
we are currently dependent on. Perovskite tandem solar cells
provide the potential for a sustainable energy future.
FIGURE 7 [22]
The growth of solar energy going down vs. the
installations of solar energy
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Olivia Yasser
Conference.
2016.
Accessed
2.22.17
http://ieeexplore.ieee.org.pitt.idm.oclc.org/xpls/icp.jsp?arnu
mber=7749896
[12] Panarina, N. “Stability Issues of the Next Generation
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8
Sydney Winner
Olivia Yasser
ACKNOWLEDGEMENTS
We are very grateful for each other for our teamwork
and hard work throughout this process. We would also like to
thank our Engineering 11 professor Dr. Karen Bursic. We
owe a lot of thanks to our conference co-chair Emelyn Haft,
without whom our paper would not have been possible.
Finally, we would like to acknowledge our writing instructor
Ms. Emelyn Fuhrman for her invaluable insights on our
assignments.
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