Solar cells Definition and 59 Threads

I have read myself through a lot of information on photovoltaics. Yet I still don't understand how it really works. From what I think I understand, the charge separation in PN junctions happens due to an electric potential build up in the depletion zone. Now according to a wikipage on organic...

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

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

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

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?

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...

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...

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...

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...

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/

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...

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...

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...

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...

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...

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...

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...

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

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...

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...

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?

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

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...

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.

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...

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...

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...

Dose anyone know that what is the newest generation of 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...

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...

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...

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...

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...

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...

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...

http://www.physorg.com/news/2011-04-solar-power-cells-hidden-magnetic.html

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...

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...

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...

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...

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...

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...

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?

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...

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...

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...

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...

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...

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?

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...