What is Solar radiation: Definition and 43 Discussions

Solar irradiance is the power per unit area received from the Sun in the form of electromagnetic radiation as measured in the wavelength range of the measuring instrument.
The solar irradiance is measured in watt per square metre (W/m2) in SI units.
Solar irradiance is often integrated over a given time period in order to report the radiant energy emitted into the surrounding environment (joule per square metre, J/m2) during that time period. This integrated solar irradiance is called solar irradiation, solar exposure, solar insolation, or insolation.
Irradiance may be measured in space or at the Earth's surface after atmospheric absorption and scattering.
Irradiance in space is a function of distance from the Sun, the solar cycle, and cross-cycle changes.
Irradiance on the Earth's surface additionally depends on the tilt of the measuring surface, the height of the sun above the horizon, and atmospheric conditions.
Solar irradiance affects plant metabolism and animal behavior.The study and measurement of solar irradiance have several important applications, including the prediction of energy generation from solar power plants, the heating and cooling loads of buildings, and climate modeling and weather forecasting.

View More On Wikipedia.org
  1. shivajikobardan

    Engineering What is difference between solar radiation and global radiation?

    Solar radiation-: it is em radiation emitted by son. it is short wave radiation. it comes in many forms. 1) visible light 2) radio waves 3) infrared 4) x rays 5) uv rays Global radiation-: it is sum of direct and diffuse radiation arriving at a ground. What are the differences between these two?
  2. B

    From weatherstation data to solar irradiation on specific surface

    So, at home I have a weatherstation which measures solar irradiation in the east, south and west in lux. I can read in these measured sensordata. From these measurements, I would like to calculate the solar irradiance on my windows. The solar energy formulas could help me with that. The work of...
  3. E

    Solar radiation on a horizontal tank

    Hello everyone, I'm looking to estimate the variation of degassing on a horizontal tank of VC (vinyl chloride) due to solar radiation. The feed flow is continuous but the outlet is batch flow. So there is a lot of variation of liquid level in the tank (constant pressure). To avoid a lot of...
  4. AN630078

    Solar Panels and Solar Radiation Flux Density Help - Very Confused

    Question 1; a) P=E/t E=5.796*10^7 J energy produced per day during the summer However, I am not certain how to calculate the time period, since although this concerns the energy produced per day, the sun does not shine for the entire duration of this 24 hour period. Also, I am unsure of the...
  5. W

    Disappearance of vapour trails - more warming?

    I think it was back around the 9-11 events that South African researchers happened to notice that solar radiation received at ground level increased by around 10% during the grounding of airline fleets world wide. If I remember correctly, this led to a measurable increase in plant growth over...
  6. A

    Convert solar radiation from Joule per cm square to Watt per meter^2?

    I have solar radiation data in the units of Joule per cm^2 (joule per square centimeter) measured hourly. I want to use this data in evapotranspiratin calculation which requires radiation units as Watt per meter squared. How can I do this conversion?
  7. F

    Solar radiation for the stabilization of satellites?

    Hi, I'm new here. I have a doubt regarding solar radiation, I heard in an astronomy class on the use of this solar radiation for the stabilization of satellites in orbit due to mechanical problems with their stabilizers. Electromagnetic waves emitted through solar radiation stabilize such a...
  8. A

    Why is solar radiation equal to long wavelength emission?

    In my heat transfer course, I always had to do analysis of long-wavelength radiation between surfaces first, and find the heat radiated from one of the surface. Then, solar radiation is added to the problem, and suddenly it was said that solar radiation=heat radiated from this surface! Does...
  9. C

    Intensity of solar radiation

    Homework Statement What is the intensity of solar radiation in a place where is the full moon ? I know luminosity of the Sun and Earth's distance from the Sun RE and Moon´s distance from the Earth RM. Trajectory of Earth and Moon are circular. Homework Equations distance of the site from the...
  10. Mnemonic

    Force due to Solar Radiation and Gravity

    Homework Statement Consider a small, spherical particle of radius r located in space a distance R = 3.75 × 1011-m from the Sun. Assume the particle has a perfectly absorbing surface and a mass density of ρ = 3.8-g/cm3. Use S = 214 W/m2 as the value of the solar intensity at the location of the...
  11. F

    Electric field on surface of the Earth due to solar radiation

    This problem is actually an example I'm working through... 1. Homework Statement We are trying to estimate the (magnitude of the) electric field in the light waves from the sun hitting the surface of the Earth. Homework Equations The Poynting vector for a sinusoidal EM wave has magnitude...
  12. T

    Calculating Heat Transfer (Thermal Radiation) to a Shipping Container

    Hello, I am trying to calculate the thermal radiation heat transfer to a shipping container which would be painted white. The purpose is to size an air conditioner for equipment, not living conditions. I have already calculated heat from the other sources. The desired internal temperature is...
  13. L

    Solar radiation force on comets.

    I see this comet being chased by ESA, they said it is presently about 500 million km from the sun. That puts the radiation received by that comet at about 10% (roughly) as what we receive on Earth, well at least on top of the atmosphere, at 1355 watts per meter ^2. Looking at the size of...
  14. O

    Access Solar Radiation Data: UV-A, UV-B & UV-C

    Does anyone have access to the current data about solar radiation reaching Earth's surface ? The most importaint is the UV range divided into UV-A, UV-B and UV-C. If not, then data from the past few years would also be fine. I need it for research but I cannot find anywhere such information.
  15. M

    Calculating the reflected power from solar radiation on the moon

    Question: The Moon has an albedo of 0.05. What is the total power of the solar radiation reflected from the Moon in units of 10^15 W? My Answer: - To get my answer i multiplied the flux density of the sun measured on the moon, then multiplied it by half of the moon's total surface area...
  16. O

    Calculating temperature increase in a building as a result of solar radiation

    I'm working on a thermal balance of a building. In particular, I'm trying to calculate the effect energy gains (mostly due to solar radiation) have on the inside temperature of the building. So I calculated the energy gains per month, for instance, 20 kW for the month of February (it's an...
  17. S

    Polymer with low solar radiation resistance, high heat resistance

    I'm an engineer student and I'm trying to build such a solar heating system that it is drum with two layers, inner one is a metal (aluminium alloy I'm thinking) water container and outer layer is made of polymer, with air gap in-between. When suns come out, it radiates through the polymer and on...
  18. W

    Stefan-Boltzman Law Proof with Regards to Solar Radiation

    Homework Statement The unit area intensity of radiation from the Sun at the photosphere is 6.33*107 W/m2. a) Check this value using the calculus of the Stefan-Boltzman Law, assuming the Sun is a blackbody emitter (\epsilon = 1) with a surface temperature of 5777K. Homework Equations...
  19. T

    Incident Solar radiation on an inclined surface

    Homework Statement Hey everyone, as part of a final year project I am looking at the economic feasibility of solar panels and whilst I have solar data for radiation intensity on flat surface, longitude (and plus or minus 15°) and 90° I am trying to find a calculation of intensity at any...
  20. T

    Intensity of solar radiation at earth orbit

    Homework Statement I am try to understand how the value of 1370 watts per metre squared for the intensity of sunlight hitting the Earth has been derived. Is there a way to see this mathematically? Homework Equations I understand about how the intensity is related to Poyntings vector, by...
  21. C

    Pool heat gain by solar radiation versus heat loss by evaporation

    Hi, On various websites I read that 70% of the heat loss of a pool is by evaporation, whereas up to 85% of the solar radiation can heat an uncovered pool. We use 22mm thick black color EPE panels to cover our pool. On a sunny day, is it better to cover the pool or to leave it uncovered ...
  22. A

    Absorption and solar radiation spectra

    Hi, I'm hoping someone can advise me on the best place to find the absorption spectra for water (fresh) and ice, for the wavelength range UV to IR. Also, I'm looking for the solar radiation spectrum at the surface of the Earth (i.e. after atmospheric effects have been taken into account)...
  23. C

    Heat Transfer (Solar Radiation)

    Homework Statement This questions relates to solar radiation and heat balance. I'm having trouble with part (b) of the question, having solved (a) already. The question is found in the following image: Homework Equations The Attempt at a Solution...
  24. T

    How do astronauts suits protect them from Solar Radiation?

    I assume, that when in orbit, astronauts are still somewhat protected by the Earths magnetic field? However, what about when they're on the moon? Does the Earths magnetic field extend that far? If not, how do they protect their bodies from harmful radiation?
  25. L

    Scattering of solar radiation

    Homework Statement A thin haze layer overlies the ground and is composed of hydrated aerosols of 0.2 micron (µm) diameter. It scatters 50% of sunlight incident upon it when the sun is directly overhead. a) What is the visible scattering optical depth of the layer? Homework...
  26. U

    Understanding Solar Radiation Force: Maths & Derivation

    I'm having a little trouble understanding this, mainly the way the maths behind it works. I can't find any kind of derivation on the internet which is 'simple' and at a level I can understand. My understanding is that the photons from the Sun are absorbed by dust, so transferring momentum...
  27. H

    Solar radiation, mars, earths and equations help please?

    Homework Statement Earth and Mars are both rocky planets, but Mars is half as far away again from the Sun as Earth, so radiation from the Sun is not as powerful at the surface of Mars as at the Earth’s surface. Using the values in Table 2, calculate the amount of solar radiation...
  28. T

    Sample rate - solar radiation

    I'm working on a solar radiation project. I was able to design a homemade pyranometer, yet I'm trying to establish what the sample rate should be. After reading several pdfs I set 60 seconds as my sample rate and I have good results, I mean if I choose 10 seconds instead I just get a lot of...
  29. M

    Solar Radiation Pressure

    The question I have is: Assume a 100 kg reflective load with 1m2 area at a distance of 1 million kilometers from the surface of the sun. If the sun’s temperature is 6000K and radius is 695,000 km, find the radiation pressure exerted on the object. Find how far the load would be from its...
  30. J

    Conical Solar Tunnel to Redirect Solar Radiation

    Am looking to build a solar tunnel that would not only redirect solar visible light radiation, but also heat, with minimum losses. Basically need to deflect angle of incident radiation by around 30 degrees. Am considering an inverted truncated cone design, with a polished inner surface...
  31. T

    Measuring Solar Radiation in Bolivia: Using LDR or Phototransistor?

    I'm trying to measure solar radiation. Unfortunately I currently live in Bolivia, so I cannot get a solar cell. Instead I wanted to use a photodiode, but I wasn't able to find that either. Do you think that it is possible to measure solar radiation using a LDR? What about a phototransistor...
  32. I

    Force of solar radiation on earth

    Homework Statement ok, well...im not sure if this is posted in the right section but I've just come across a past exam question that is supposed to be in classical mech and relativity section of the paper... If 1.3kW/m2 of solar radiation falls on the Earth at midday at the equator what is...
  33. R

    Emitted radiation and absorbed solar radiation

    Jupiter has a black body temperature of 125K, but this is 20 K higher than the temperature that would be calculated from absorbed solar radiation alone. From this information, calculate the ratio of emitted radiation to absorbed solar radiation on Jupiter. I started using W = sigma * area...
  34. D

    Comparing Illuminance and Solar Radiation in Dragonfly Habitat

    Hello, I'm working on a GIS modeling project where I'm trying to predict dragonfly habitat. I have collected my field data using a hand-held meter that measures illuminance in lux. I am wanting to incorporate some other spatial data I derived using a digital elevation model which shows solar...
  35. D

    Solar Radiation AM - Danilo's Question

    First of all, this is my first post here. So, hello everyone! :smile: I have a question about the solar radiation and that I don't seem to be able to find an answer for on the net. I'm building an IR transceiver for data transmission that should be able to withstand some amount of direct...
  36. Z

    The peak frequency of solar radiation?

    Hey guys. The question I have to answer is What is the color of the peak frequency of solar radiation? Now is there a certain way to figure this out or...very hard to find on the internet... best zach
  37. S

    Solar Radiation and Nuclear Waste

    I am looking for detailed information to understand the actual differences between solar radiation from the Sun and radiation from High Level Nuclear waste. What are te similarities? What are the differences? What tools and methods can be used to measure the strength of each? I what...
  38. G

    Acceleration due to solar radiation pressure

    Q: Near the Earth the flux of the EM energy from the sun is ~ 1.4 kW/m2. If an interplanetary sailplane has a sail of mass 1g/m2 and negligible other weight, what would be its acceleration due to solar radiation pressure? Help! I am a stuck on this. However, I have a few thoughts: We know...
  39. S

    Calculating Earth's Energy Loss and Temperature Increase Due to Solar Radiation

    If the amount of solar energy striking the outer edge of the earth’s atmosphere is approximately 1.4 kW/m2 and the amount of the earth’s surface area exposed to the sunlight is 1.6 x 10E13 m2, how much energy does the Earth lose through radiation within each 24 hours? The average Earth...
  40. B

    Solving a Puzzling Solar Radiation Problem

    Hi guys I'm flicking thorugh some past papers for an upcoming exam and came across this seemingly easy problem. "The average intensity of solar radiation at the Earth is 1.4kW/m^2. Assuming the Earth is a perfect absorber, calculate the force exerted by the radiation on the surface of the...
  41. tony873004

    Formula for solar radiation pressure

    Formula for solar radiation pressure I'm looking for a formula that gives the amount of force in Newtons that is produced from the pressure of solar radiation. I've googled it and found: F_R = C_R \frac{I}{c}S where I is the radiation intensity, c is the speed of light, and S is the...
  42. S

    Efficiency is 13% for CO2 fixation using solar radiation Photosynthesi

    What is the approx. efficiency of the conversion of light energy to chemical energy in photosynthesis? a. 100% b. 95% c. 15% d. 1% I doubt that it is 100%. Is it 15%? I did a search, and I read that the efficiency is 13% for CO2 fixation using solar radiation. I don't know if this is...
  43. N

    Difference between insolation and solar radiation

    Insolation.!what is it ? i mean what is the differnce between insolation and solar radiation.