What is Solar cells: Definition and 58 Discussions

A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as solar panels. The common single junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 to 0.6 volts.Solar cells are described as being photovoltaic, irrespective of whether the source is sunlight or an artificial light. In addition to producing energy, they can be used as a photodetector (for example infrared detectors), detecting light or other electromagnetic radiation near the visible range, or measuring light intensity.
The operation of a photovoltaic (PV) cell requires three basic attributes:

The absorption of light, generating either electron-hole pairs or excitons.
The separation of charge carriers of opposite types.
The separate extraction of those carriers to an external circuit.In contrast, a solar thermal collector supplies heat by absorbing sunlight, for the purpose of either direct heating or indirect electrical power generation from heat. A "photoelectrolytic cell" (photoelectrochemical cell), on the other hand, refers either to a type of photovoltaic cell (like that developed by Edmond Becquerel and modern dye-sensitized solar cells), or to a device that splits water directly into hydrogen and oxygen using only solar illumination.
Photovoltaic cells and solar collectors are the two means of producing solar power.

View More On Wikipedia.org
  1. B

    Why Are Solar Panels 21-22% efficient? How can efficiency improved?

    How efficient are solar panels? How can their efficiency improve? Besides their benefits, what are the ecological impacts of solar energy?
  2. W

    I Question about electromagnetic spectrum and solar cells

    Would it be possible to change all wavelenths to one frequency that would then be sent to a solar panel adapted for it, or once split could to be sent to cells that work in that range? In other words use all the light to produse electric power
  3. cemtu

    Why do monocrystalline solar cells have rounded/cropped edges?

    There were circular solar cells 30 years ago. Why do we have square-shaped solar cells now? Why square now?
  4. cemtu

    Purity of Polycrystalline Solar Cells vs Monocrystalline Solar Cells

    Why is the silicon purity of polycrystalline Solar Panels lower than monocrystalline Solar Panels? I have read this explanation somewhere in the internet but not sure if it is correct? Can somebody give me an explanation please?
  5. Mayan Fung

    I Recombination and open-circuit voltage in solar cells

    From the ideal diode model, we can derive the open-circuit voltage (Voc) as: $$ V_{oc} = \frac{nkT}{q} ln(\frac{I_L}{I_0} + 1) $$ where ##I_0## is the dark saturation current and ##I_L## is the light generated current. From the model, if the recombination rate increases, the dark saturation...
  6. P

    Is Wall-Mounted Solar Production More Efficient in Winter at High Latitudes?

    I live at 60 degrees north. On december 22nd the sun is only 8 degrees above the horizon at noon. Here lots of people say they would go off grid if they just could have a reliable electricity production during the winter. All the sellers of solar cells talks about maximizing the cells production...
  7. V

    Second reflection angle of incidences in 3D

    Given Theta1(angle of incidence) and alpha1(azimuth angle). how do we obtain the second reflection angle theta3 and alpha3? Assuming the surface to be a mirror reflection(theta1 = theta2). Need an equation when varied the incident angles we would obtain the second reflection angles or a method...
  8. Mayan Fung

    Perovskite solar cell J-V scan

    Hi all, I am working on perovskite solar cell related studies. J-V curve (current density-voltage curve) is one of the important measurements to determine the performance of the device. In practice, we perform the reverse scan first then then followed by the forward scan. There is usually a...
  9. The Path to Perovskite on Silicon PV | Prof. Henry Snaith

    The Path to Perovskite on Silicon PV | Prof. Henry Snaith

    In this interview, Prof. Henry Snaith (University of Oxford) discusses the present status and future prospects of perovskite PV. Article: https://scivpro.com/manuscript/10_32386_scivpro_000004/
  10. E

    B Solar cells - how do they repeat the process?

    Hey everyone, I have to do this presentation about solar cells and how they work. I've been doing a lot of research, and now I know a lot about how they work. However there is just one thing, that I can't understand. So in a solar cell there is an N-type and P-Type. The N-type has too many...
  11. Mayan Fung

    Degradation of crystalline silicon solar cells

    Hi there, it is commonly accepted that the lifespan of crystalline silicon solar cells is about 20-30years. And they define the lifespan as when the solar cells efficiency drop to about lower than 10%. However, what are the possible reasons for the degradation? I can only find research papers...
  12. N

    I Are solar cells operated under any kind of bias or not?

    Hello all, I am having a very hard time understanding the operating principles of solar cells. I'm mostly confused about what external biasing conditions a solar cell operates under. I have tried googling this question and I get different answers (see the links below). For the TL;DR version...
  13. B

    How do solar cells generate current from pn-junctions?

    Looking for a practical description. I have a feeling I am grossly misunderstanding something fundamental about electric circuits and apologize if my questions are confusing because of it. I have these two sources: acs hyperphysics My (probably naive) understanding of the process is as...
  14. Clara Chung

    Why Does Arranging Solar Cells in Series and Parallel Increase Power Output?

    Homework Statement My book states that solar cells are joined in series and in parallel to give a greater power because P=VI is increased by increasing V and I. Homework EquationsThe Attempt at a Solution I assume that the current in the solar cells depend on the intensity of sunlight. The...
  15. B

    Calculating Power with Solar Cells: Series vs. Parallel

    So I am trying to figure out how much Wh I would have with these solar cells I have. Each solar cell is rated to have 2.8w. Does this mean if I have 40 of them I would have 112 wh? I am going to be putting the solar cells in series. Does this affect the power? I know adding in series is good...
  16. Jafar Hussain Shah

    Charge Separation and solar cells?

    hi, i want to know that how many techniques are being used for charge separation? and which one is more effective for solar cell? can you give some idea about it that which one is better and how to make better power conversion efficiency. after going thoroughly through literature review i am...
  17. U

    What is the (n,k) value of hydrogenated amorphous silicon carbide?

    Hello, I'm working on simulation of hydrogenated amorphous and microcristalline silicon solar cells. The software I use is AMPS 1D So, I need (n,k) of hydrogenated amorphous silicon carbide (a-SiC:H) Thank you
  18. Physicist50

    Solar Cells & Refractive Index

    Hi there, I have recently been researching in depth solar cells/panels, the parameters of their efficiency and the photoelectric effect in general, specifically how different wavelengths of light affect it. My research has yielded a few facts; that the efficiency of standard silicon solar cells...
  19. E

    Efficiency calculation for solar cells

    Homework Statement Hi! I have a problem with the following problem: Calculate the efficiency of the solar cells with the characteristics given in the table below Power (28 degrees, BOL): 300 W/m2 Absorptance: <91 , emittance: >82. Reliability: 0.999 . Mass: 2 kg Homework Equations I know...
  20. Sayani Ghosh

    Schottky junction solar cells

    I was wondering in Schottky junction solar cells, how is the open circuit voltage dependant on the built in potential and the Schottky Barrier Height?
  21. avito009

    How is electricity produced from solar cells?

    Is electricity produced from solar cell because light has electric and magnetic fields?
  22. T

    Verifying my understanding of solar cells and semiconductors

    My base understanding of the solar cell is as follows: Light hits metal in solar cell and emits electron via photoelectric effect. There is n-type silicon which has an overall negative charge due to excess electrons. There is also p-type silicon which has an overall positive charge due to a...
  23. D

    What is the top solar cells in market?

    What is the highest efficient solar cells out there? I heard there was one that is 80% efficient. And there is a clear solar cell but less efficient which are transparent ones.
  24. D

    Why do we need tandem solar cells?

    I have a general question about tandem solar cells. So tandem solar cells are solar cells with multiple p-n junctions in them. However, why can't we have a single junction solar cell with multiple wavelength absorbers in them? That is to say, why do tandem solar cells need to be split...
  25. G

    Optimizing Solar Panel Efficiency: Calculating Sunlight for Maximum Power"

    How can I calculate the total diffused and incident light of the sun?Edit I am doing this project with solar panels. I thought, watching as well several youtube videos, that I could improve the panels with mirrors, and looking at some plants, I realized that some of their leaves bended towards...
  26. J

    Is a Sun-Solar Cell System Truly Equivalent to a Carnot Engine?

    I have undertaken a course on Semiconductors. My professor told us that a sun-solar cell system can be taken as a Carnot Engine. He assumed that the surface temperature of sun is 6000k and that of solar cell is 300k.And then he found out the efficiency by (1-T1/T2), which came out close to be...
  27. H

    What Is the Newest Generation of Solar Cells?

    Dose anyone know that what is the newest generation of solar cells?
  28. K

    Efficiency Of Thin Film Solar Cells

    How does the efficiency of a Thin Film solar cell compare to the efficiency of a single crystal solar cell with reference to the 5 main solar cell parameters ( Iopt , Rs, Rsh, Is and n )? I know series resistance( Rs ) will probably increase in thin film cells because of grain boundaries...
  29. TheFerruccio

    Solar cells in parallel and series

    Hi, I am conducting an experiment whereby I have to measure the individual performance (on a per-cell basis) of solar cells on a solar panel. The panel has 20 cells, which are 4 strings in parallel of 5 cells in series each. The entire panel has a +V and chassis GND wire that I can open or...
  30. E

    Why Asymmetrical Junctions are widely used in Solar Cells? What Advantages?

    Hello, I was investigating 'Asymmetrical P-N Junctions'. If the doping concentration of the P and N type semiconductors are different then the P-N junction they will form will be a asymmetrically doped Junction. I searched and come up with the fact that 95% of the solar cell structures are...
  31. D

    Solar cells: How much they absorb, reflect and diffuse

    Hey folks not sure if this is the right section but I'll give it a go... I'm trying to out find out what percentage of photons a solar cell (preferably gallium arsenide solar cells) will absorb, reflect and diffuse. I have read, from a few links, that the highest absorption rate for silicon...
  32. S

    Solar Cells that can absorb energy from bulbs/Tubelights

    Hi, I am sorry if this is in the wrong place. I had an idea of using Polymer-fullerene solar cells (http://en.wikipedia.org/wiki/Konarka_Technologies#Polymer-fullerene_solar_cells) in Mobile phones to recharge its battery using Indoor lights. But , unfortunately, these cells are of...
  33. L

    Question about the concept of electricity in solar cells.

    Ok so I understand how a voltage source works, with electrons flowing from a high potential to a low potential. But I'm a little confused about solar cells. So the way they work is that an incoming photon strikes an electron and gives it enough energy to break free and create a current. But...
  34. A

    Calculating Output of Solar Cells in KWH

    hi, I am working on a small solar cell project for which i bought two small solar cells panels of 6volt each producing current of 5.263milli ampere in combination. I want to know that how can i calculate the values of solar cells output in kwh, on the output i have placed two bulbs of 3 volts...
  35. D

    Solar Energy Without Solar Cells?

  36. M

    Phosphor Powder for solar cells

    someone just asked this as a comment on an article i was reading http://home.howstuffworks.com/fluorescent-lamp6.htm 'Does a phosphor powder give off a photon or electron when struck by light?' I was just thinking maybe a solar cell made of phosphor powder to emit electrons. I...
  37. Q

    Are solar cells more efficient for specific frequencies of light?

    my understanding is that energy is wasted in a solar cells when light with more frequency than necessary to make an electron cross the band gap comes along and the excess energy is converted to heat. does this mean if you only shined blue light at a solar cell which had a perfect electron gap...
  38. C

    Most Recent Guide to making Solar cells?

    Hello my friends, first I want to thank all of those who take their time to helping people like us. I have a question and is what is the most recent guide on making a very powerful Solar Cell, I am very interested in it, and the reason why I want to know this is for making more devices to cut...
  39. S

    Charge separation in solar cells

    If there is a charge separation on macroscale in a solar cells (electrons flow in one direction and holes in another) why there is no high voltage build up similar to capacitors or piezoelectrics where also charge separation occur? There exist some glasses which become conducting when heated...
  40. S

    Solar Panels Q&A: Questions on Efficiency & Currents

    I have the following questions regarding solar panels. 1)Why solar panels which use sunlight concentrators gain in efficiency despite they produce larger currents?Usually it`s believed that with increase in current flow efficiency should fall. Example here is a fuel cells. 2)Currently...
  41. D

    Solar Cells in Forward/Reverse Bias?

    Considering this is for a condensed matter course, I'm assuming it'll belong here :) I cannot, for the life of me, figure out why solar cells are operated in forward bias as that would counteract the electron-hole separation in the depletion zone. Wouldn't it make more sense to operate them...
  42. E

    The theoretical maximum efficiency of silicon solar cells is about 29%. Why?

    The theoretical maximum efficiency of silicon solar cells is about 29%. How is this theoretical maximum efficiency derived? How can I use the working principles of a silicon solar cell to explain this?
  43. D

    Clarification on semiconductor physics in solar cells

    So, I am doing a little bit of research on how energy is created in solar cells. From what I understand, there is just a whole bunch of n and p junctions connected to each other electrons flow the same way. Or, electrons travel one way, and holes travel the other. So when you dope the silicon...
  44. F

    Solar cells and electric fields

    This image confuses me a tad. We have the n-type (negative) silicon and the p-type (positive) silicon plates. We put the plates together. The electrons are in a rush to fill the positive "holes" on the p-side, and the positive holes are in a rush to to the n-side, to the electrons. Between...
  45. M

    How Does the Fermi Level Influence Solar Cell Voltage?

    Hello, Im working on a paper on solar cells and i came across the term "Fermi level". What exactly is the Fermi level in this context: "The working voltage produced by the device is the difference between the chemical potential of the titanium dioxide (Fermi level) and the redox...
  46. K

    Impedance Spectra of Dye-Sensitizedd Solar cells

    Can anyone tell me how can I take the impedance spectra of a dye-sensitized solar cell ? Do I need to irradiate (i.e. AM 1.5, 100 mW/cm2) the solar cell during impedance measurement? or I can measure the spectra without irradiating light ? More specifically, how can I get the comparison between...
  47. E

    What are the issues when using Solar Cells in Ocean Environments?

    This question would perhaps be an ocean engineering question, but since we don't have a forum for that, I thought mechanical engineers would have some idea about this. My background is electrical engineering, and I have little knowledge about the mechanical issues when operating at the surface...
  48. G

    Does Simulating 3-D Structures Enhance Polymer Solar Cell Efficiency?

    Is it useful simulating a 3-D structure of a polymer solar cell? Is there a particular internal structure for a polymer solar cell which is most efficient?
  49. Phrak

    Calculating the Energy Cost of Manufacturing Solar Cells: Factors to Consider

    How much electrical energy does it take to manufacture a solar cell? I'm curious about the break-even time. Silicon boules are grown in an over--probably electric. More machining follows. If the frame is aluminum, it's smelted in an electric arc furnace. This is really an oversimplifed...
  50. D

    Programs Masters/PhD - Research in Organic Electronics / Solar Cells

    Hi, I was looking around at graduate schools and was curious if anyone knew of places where they are doing research into organic electronics or organic photovoltaics? I found a research department at MIT and Stanford, but I was looking for something perhaps one tier below that. It...