Photovoltaic Cell Feasibility Study Essay: Part 1

By Thompson Kum

Throughout this essay, one hopes to provide a suitably comprehensive feasibility study into the application of photovoltaic (PV) cells as a form of energy generation to meet increased energy demands in the 21st century with respect to the greenhouse effect, photovoltaic effect, and the positive and negative implications of its widespread implementation. The focal point of this study is to investigate how to facilitate environmentally sustainable methods of economic development and meeting energy demands in the 21st century, more specifically, the issue of carbon related emissions through the greenhouse effect. Part 1 will focus on establishing and explaining the scientific principles behind how PV cells function.

According to the IEA, global net carbon dioxide emissions have increased by 0.8% since 2024; this has resulted in the release of 37.8 gigatonnes of carbon dioxide, which is equivalent to 150% of pre-industrial levels of atmospheric CO2. CO2 emissions from the combustion of fossil fuels for energy have increased by ≈ 1% since 2024 (which is equivalent to a whopping 357 megatonnes).

However, beyond understanding there to be a general increase in the release of carbon dioxide due to human activities, it is imperative to address what has necessitated this increased release in the first place. In emerging markets and developing economies, energy related carbon dioxide emissions have increased by 1.5% (375 megatonnes of CO2) in 2024 to meet energy demands associated with rapid economic and population growth. (IEA, 2025)

In addition to the above, electricity demands also grew more rapidly than the net energy demand and GDP, increasing by 4.3% in 2024, due to increased access to electricity intensive appliances, manufacturing, and artificial intelligence in daily life and usage. Lastly, the prevalence of this issue is a particularly pertinent matter in Asia, where the demand for natural gas grew by 2.7%, with more than 7% of the growth being attributed to China and more than 10% of the growth being attributed to India. This was due to increased industrial usage and rates of power generation to accommodate for the extreme weather conditions in the regions. Therefore, a vicious cycle is established as emissions fuel abnormal weather, abnormal weather drives natural gas and energy demands, and demands induce emissions (IEA, 2025).

To elucidate this point further, the relevance of petroleum in energy generation revolves around the conversion of the stored chemical potential energy into electrical energy through combustion in electricity generators. The current mechanism works by the release of heat following the combustion of the fuels, providing sufficient latent heat for the boiling of water to form high pressure steam which is then used to spin a turbine. The turbine then induces the spin of the armature of a generator, inducing a change in magnetic flux that creates a circular electric field to provide an EMF for current flow in a conductive wire, according to Faraday’s Law of electromagnetic induction.

Whilst this is a fine method of electricity generation, and is more effective than current environmentally friendly options (20-30% efficiency as compared to apx. 12-18% efficiency), it contributes greatly to the greenhouse effect and fails to achieve the circular economy, where resources can be recycled and a linear “take-make-waste” production cycle is absent to prevent the depletion of non-renewable materials.

To elaborate further on the greenhouse effect, the mechanism of heat absorption into the Earth’s system works by the sun’s emission of infrared, visible light, and ultraviolet radiation, which then mostly passes through the atmosphere. Upon passing through, it is partially absorbed into the land due to it possessing sufficient wavelength and hence energy (E=h(v/λ)) to induce greater nucleon vibration, electron excitation, or ionisation when contacting the particles it comes into contact with on Earth. The remaining radiation is reflected as infrared radiation which is then absorbed by the greenhouse of the atmosphere, where heat is re-emitted in all directions, creating a heat trapping effect (SaveMyExams, 2026).

By disrupting the natural amount of greenhouse gases such as carbon dioxide and methane in the atmosphere, this heating effect is amplified, which can cause great disruptions in the stability of the Earth’s habitat by altering the environmental conditions that are normally carefully balanced to ensure the survival of species in their habitats (e.g. the temperature conditions for the optimal functioning of enzymes to prevent denaturation or rates of transpiration).

By disrupting the survival of the species in their habitats the functioning of the carbon and nitrogen cycles are disrupted, which affect the availability of general resources and can further contribute to the incidence of extreme weather events, which in turn increases energy and electricity demand, hence a horrid cycle is established.

Therefore it is imperative to explore alternative methods of electricity generation that do not rely on the combustion of petroleum-based fuels. PV cells serve as an excellent alternative that is both environmentally and economically sustainable, whilst meeting the prevalent energy and electricity needs of the communities most in need of it. The PV cell brilliantly utilises the photovoltaic effect, which involves the excitation of electron hole pairs in an electric field to create a constant flow of ions to create a current.

On a fundamental level, it is important to first understand what drives the movement of current — it is the difference in electric potential between two areas and the subsequent electromotive force between these two areas. But what is electric potential? To understand that, one must first investigate electrostatic potential energy. Electrostatic potential energy is defined as the work done by an external force to move a point charge from a distance infinitely far away from the electric field of a positive source charge (where field strength is 0) to its current position in the field, where work is done against the electrostatic forces attraction or repulsion by the field, and there is no change in the kinetic energy of the point charge itself (in physics the work done to move the charge itself without an electric field can be thought of as negligible).

To understand further why the electrostatic potential energy is determined by the position of the point charge, the simple concept of field line density should be clearly understood. As the field line density of the electric field radiating from a source charge is inversely proportional to the distance between it and the point charge, decreasing the distance increases the amount of electric forces acting to repel it, hence electrostatic potential energy is greater at a smaller distance. Conversely if the charges are unlike, the electrostatic potential energy is directly proportional to the distance between the charges if other variables remain constant due to there being more work done to separate the charges due to electric forces of attraction. (For convenience of understanding look to Ue = (kq1q2)/r).

The electrostatic potential energy of a charge is proportional to the magnitude of the charge itself and the source charge, and the degree of separation between them (the Coulomb’s constant does not change), and as the electrostatic potential energy of a substance is determined by the sum of the energies of its point charges, it is imperative to analyse the electron configuration of the substance to determine its electric potential. Despite the electrostatic potential energy of a point charge being a scalar quantity, it still has a sign to indicate the electric forces between the charges (positive means like charges, negative means unlike charges, hence decreasing the degree of separation between the two charges increases electrostatic potential energy for like charges and vice versa for unlike charges).

Lastly, to understand the movement of charges, as electrostatic potential energy is a measure of the work done by an external force against electric forces of an electric field from a positive source charge without a change in the point charge’s kinetic energy, one can therefore understand that the electric forces of the source charge induce a conversion into electrostatic potential energy into kinetic energy, where the change in electrostatic potential energy is equal to the negative of the work done by the electric field to induce the displacement of the charge from its current position. In essence it is the electric forces of the electric field that induce the movement of charges by the conversion of stored electrostatic potential into kinetic energy, hence EMF is really a measure of the work done by the electric field between the anode and cathode on the electrons in a circuit (Openstax, 2026; Perplexity 2026).

Now that a baseline understanding of the scientific principles of electrostatic potential have been established, let us explore electric potential. Electric potential is defined as the electrostatic potential energy per unit charge, and it is a key observed property that electrons move from an area of lower electric potential to higher electric potential, and vice versa for positive charges, due to areas of lower electric potential having an accumulation of negative charge, and vice versa for areas with a higher electric potential. By placing a region of high electric potential with an area of low electric potential in conjunction with each other, electric forces are able to act on the charges of each region due to the interactions of their respective electric fields, and a potential difference and EMF that drives current flow is defined due to the introduction of the charged areas into each other’s systems.

A PV cell uses this concept to generate electricity — two layers of polysilicon (a p-layer and n-layer) are placed close together. The special property of polysilicon is that in addition to it being a semiconductor material that enables the movement of charge through it, it foregoes the typical inert tetrahedral structure of polysilicon, where covalent bonds are instead formed with embedded boron at the p-layer and with phosphorus at the n-layer. The unique covalent bonding of the p-layer makes it so that the shared energy levels between the boron and silicon lack one electron for a neutral charge due to boron only having 3 valence electrons and silicon having 4, hence a hole is formed. Conversely in the n-layer as phosphorus has 5 valence electrons, there is an excess electron that makes the n-layer negatively charged. By placing these two plates in conjunction with each other, the points of contact form a “depletion layer”, where the strong electric forces of the two plates induce the breakage of the covalent bonds in the polysilicon and the subsequent movement of electrons to the p-layer and vice versa for the holes. Electron hole pairs are now formed at the depletion layer, where the n-layer portion becomes positively charged by the accumulation of holes and the p-layer becomes positively charged.

However, the brilliance of PV cells lies in how it utilises the photovoltaic effect. Fundamentally the movement of charges has halted without after the complete formation of the depletion layer — the electrons and holes not at the depletion layer are not in close enough proximity to the oppositely charged layer to break their covalent bonds and be free to move to the depletion layer, and the charges of the depletion layer have successfully moved down their electric potential gradient.

To alleviate this, ionisation energy is introduced into the system. The infrared, visible light, and ultraviolet radiation emitted by the sun can be conceptualised as photons according to wave-particle duality, where photons are thought of as excitations of the electric and magnetic fields that exist around us. Upon the photon contact with the electron hole pairs at the depletion layer and both layers of polysilicon, the radiation possesses sufficient energy to induce the breaking of the covalent bonds and the electron hole pairs, which allows the electrons at the depletion region to move back to the n-layer due to the layer now being positively charged, and vice versa for the holes. Simultaneously this allows the movement of charges in both layers towards the depletion layer due to the breaking of covalent bonds in the polysilicon. The culmination of the above enables charge movement once more, and hence the establishment of a current. Furthermore, the constant redistribution of charges between the layers at the depletion region due to the movement of electrons and holes does not require the loss of mass of an electrode as with typical electrochemical cells due to the nature of charge diffusion across an electric potential gradient, hence PV cells align with the circular economy in the sense that materials are not used up (Spirit Energy, 2026; Circuit Mechanics 2025).

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Stay tuned for Part 2!