Solar Basics
- Page ID
- 5897
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)After beginning with a series of pages of introductory physics to bring non-scientists up to speed, this section will delve into the fundamentals of solar physics in a way that can be understood by those who are not experienced in scientific studies. A main goal of this project is to provide key information and details about solar research for researchers, students, and the public in general, and this section is an effort to include even those who may not be fluent in the language of mathematics in our efforts. For those who are more trained and capable in physics and mathematics, the Advanced section will be more appropriate. However, all are invited to learn the concepts of solar physics from the pages that are to follow.
- B. Basics of the Sun
- I. Properties of Light
- 1. The Electromagnetic Spectrum
- 2. Photon Energy and Flux
- 3. Spectral Irradiance
- 4. Radiant Power Density
- II. The Sun As a Source of Radiation
- 1. Black Body Radiation
- 2. Nuclear Fusion
- 3. Convection and Solar Radiation
- III. Solar Radiation Outside the Earth's Atmosphere
- IV. Atmospheric Effects on Solar Intensity
- V. Air Mass
- VI. The Sun's Motion
- VII. Radiation Capture at the Surface
- C. Semiconductors and Solar Interactions
- I. Basic Properties of Semiconductors
- 1. Electron Excitation and Holes
- 2. Bond Model of a Group IV Semiconductor
- 3. Band Gaps
- 4. Fermi Energy Levels
- II. Conduction in Semiconductors
- 1. Intrinsic Carrier Concentration
- 2. Impurities in Semiconductors
- 3. Equilibrium Carrier Concentration
- 4: Carrier Drift and Mobility
- 5. Diffusion Current
- III. Absorption of Light and Generation
- 1. Absorption Coefficient and Penetration Depth
- 2. Direct Semiconductors
- 3. Indirect Semiconductors
- 4. Other Absorption Processes
- IV. Recombination of Charge Carriers
- 1. Lifetime and Doping
- 2. Radiative (Band-to-Band) Recombination
- 3. Auger Recombination
- 4. Recombination with Defect Levels (Shockley-Read-Hall)
- V. Equations of Device Physics
- E. Solar Cell Operation
- I. Ideal Solar Cells
- 1. Solar Cell Structure
- 2. Light Generated Current
- 3. Collection Probability
- 4. Quantum Efficiency
- 5. Spectral Response
- II. Solar Cell Parameters
- 1. Current-Voltage Characteristic of an Infinite Solar Cell
- 2. Short-Circuit Current
- 3. Open Circuit Voltage
- 4. Fill Factor
- 5. Efficiency
- III. Resistive Effects