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<onlyinclude>'''Insolation''' is the incident [[solar radiation]] onto some object. Specifically, it is a measure of the [[solar energy]] that is incident on a specified area over a set period of time. Generally insolation is expressed in [[kilowatt-hour]]s per square [[meter]] per [[day]].</onlyinclude><ref>Alternative Energy. (August 4, 2015). ''What is Insolation?'' [Online]. Available: http://www.altenergy.org/Glossary/insolation.html</ref>
''This term is somtimes confused with ''[[insulation]]''.


Not all of the [[Solar energy to the Earth|solar energy that reaches the Earth]] actually reaches the surface of the [[Earth]]. Although 1367 W/m<sup>2</sup> of [[sunlight]] strikes the outer [[atmosphere]], about 30% of it is reflected back into space. After this reflection, a certain spot on the Earth might see almost all or almost none of this sunlight. There are many factors that help determine how much sunlight actually reaches a given area, but some of them include [[sun]] angle<ref>angle the sun makes with the perpendicular of the surface</ref>, [[air]] [[mass]], day length, cloud coverage, and [[pollution]] levels.<ref name="RE1"> A.Watson, D.Watson. (August 5, 2015). ''Insolation'' [Online]. Available: http://www.ftexploring.com/solar-energy/insolation.htm</ref>
<onlyinclude>'''Insolation''' is the incident [[solar radiation]] onto some object. Specifically, it is a measure of the [[solar energy]] that is incident on a specified area over a set period of time. Generally insolation is expressed two ways. One unit is [[kilowatt-hour]]s per square [[meter]] (kWh/m<sup>2</sup>) per [[day]] </onlyinclude><ref>Alternative Energy. (August 4, 2015). ''What is Insolation?'' [Online]. Available: http://www.altenergy.org/Glossary/insolation.html</ref> which represents the average amount of [[energy]] hitting an area each day. Another form is [[watt]]s per square meter (W/m<sup>2</sup>) which represents the average amount of [[power]] hitting an area over an entire year.


[[File:Insolation.png|400px|framed|center|Figure 1. Two maps showing where solar insolation is the greatest. The top image shows the insolation levels at the top of the atmosphere, the bottom image is solar insolation values at ground level.<ref>Wikimedia Commons. (August 4, 2015). ''Insolation'' [Online]. Available: https://commons.wikimedia.org/wiki/File:Insolation.png</ref>]]
Not all of the [[Solar energy to the Earth|solar energy that reaches the Earth]] actually reaches the surface of the [[Earth]]. Although 1367 W/m<sup>2</sup> of [[sunlight]] strikes the outer [[atmosphere]], about 30% of it is reflected back into space. After this reflection, a certain spot on the Earth might see almost all or almost none of this sunlight. There are many factors that help determine how much sunlight actually reaches a given area, but some of them include [[sun]] angle<ref>angle the sun makes with the perpendicular of the surface</ref>, [[Solar spectrum|air mass]], day length, cloud coverage, and [[pollution]] levels.<ref name="RE1"> A.Watson, D.Watson. (August 5, 2015). ''Insolation'' [Online]. Available: http://www.ftexploring.com/solar-energy/insolation.htm</ref>


When solar [[radiation]] hits an object, some of the [[energy]] will be absorbed while the rest is reflected. Generally the absorbed solar radiation is converted to [[thermal energy]], which causes the object to [[heat]] up. In some cases, however, the incident energy can be absorbed and converted into another form of energy. This is the case in [[photovoltaic cell]]s used on [[solar panel]]s. Thus understanding insolation (the amount of energy that hits an area) is important in maximizing the output of solar panels which absorb and convert this energy. Factors such as the geographic location of solar panels and altitude they should be placed at for maximum output can be determined by understanding insolation values.<ref name=sol>Solar Insolation. (August 6, 2015). ''Solar Insolation'' [Online]. Available: http://solarinsolation.org/</ref>
[[File:Insolation.png|400px|framed|center|Figure 1. Two maps showing where solar insolation is the greatest. The top image shows the insolation levels at the top of the atmosphere, the bottom image is solar insolation values at ground level.<ref>Wikimedia Commons. (August 4, 2015). ''Insolation'' [Online]. Available: https://commons.wikimedia.org/wiki/File:Insolation.png</ref> For more information about why these values are so much lower than the incident 1367 W/m<sup>2</sup> [[Solar energy to the Earth|click here]]]]
 
When solar [[radiation]] hits an object, some of the [[energy]] will be absorbed while the rest is reflected. Generally the absorbed solar radiation is converted to [[thermal energy]], which causes the object to [[heat]] up. However in some cases, the incident energy can be absorbed and converted into another form of energy. This is the case in [[photovoltaic cell]]s used on [[solar panel]]s. Thus understanding insolation (the amount of energy that hits an area) is important in maximizing the output of solar panels which absorb and convert this energy. To maximize output, factors such as the geographic location of solar panels and [[Solar collector orientation|orientation]] can be determined by understanding insolation values.<ref name=sol>Solar Insolation. (August 6, 2015). ''Solar Insolation'' [Online]. Available: http://solarinsolation.org/</ref>


==Importance==
==Importance==
It is important to have values for insolation at certain positions on the Earth as these figures are used to help determine the size of [[solar power]] systems. Values for insolation can help to determine the expected output for solar panels and determine where on Earth solar panels would be most effective.<ref name=sol/>
It is important to have values for insolation at certain positions on the Earth as these figures are used to help determine the size and output of [[solar power]] systems. Values for insolation can help to determine the expected output for solar panels and determine where on Earth solar panels would be most effective.<ref name=sol/>


As well, insolation is an important consideration in construction. When constructing a building in a particular [[climate]], it is important to understand what the [[temperature]] and sun levels will be like to ensure maximum comfort and [[energy efficient building design|energy efficiency]]. Understanding insolation can help to build buildings that are cool in the summer and warm in the winter by installing large [[window]]s on the side of the building that faces the equator.<ref name=sol/> Doing this maximizes insolation in the winter while minimizing it in the summer.
As well, insolation is an important consideration in construction. When constructing a building in a particular [[climate]], it is important to understand what the [[temperature]] and insolation will be like to ensure maximum comfort and [[energy efficient building design]].  


Patterns of insolation also help to explain why the polar regions of the Earth are colder than equatorial regions.<ref name=sol/> Figure 1 shows a map indicating where solar insolation is at its highest and lowest. Understandably, the sun shines less directly for less time in colder polar regions, and more in hotter equatorial regions. This helps to partially describe why climates vary around the globe.
==For Further Reading==
*[[Solar panel]]
*[[Solar power]]
*[[Solar energy to the Earth]]
*[[Thermal energy]]
*[[Radiation]]
*Or explore a [[Special:Random|random page]]


==References==
==References==
{{reflist}}[[Category:Uploaded]]
{{reflist}}[[Category:Uploaded]]

Revision as of 21:15, 8 June 2018

This term is somtimes confused with insulation.

Insolation is the incident solar radiation onto some object. Specifically, it is a measure of the solar energy that is incident on a specified area over a set period of time. Generally insolation is expressed two ways. One unit is kilowatt-hours per square meter (kWh/m2) per day [1] which represents the average amount of energy hitting an area each day. Another form is watts per square meter (W/m2) which represents the average amount of power hitting an area over an entire year.

Not all of the solar energy that reaches the Earth actually reaches the surface of the Earth. Although 1367 W/m2 of sunlight strikes the outer atmosphere, about 30% of it is reflected back into space. After this reflection, a certain spot on the Earth might see almost all or almost none of this sunlight. There are many factors that help determine how much sunlight actually reaches a given area, but some of them include sun angle[2], air mass, day length, cloud coverage, and pollution levels.[3]

Figure 1. Two maps showing where solar insolation is the greatest. The top image shows the insolation levels at the top of the atmosphere, the bottom image is solar insolation values at ground level.[4] For more information about why these values are so much lower than the incident 1367 W/m2 click here

When solar radiation hits an object, some of the energy will be absorbed while the rest is reflected. Generally the absorbed solar radiation is converted to thermal energy, which causes the object to heat up. However in some cases, the incident energy can be absorbed and converted into another form of energy. This is the case in photovoltaic cells used on solar panels. Thus understanding insolation (the amount of energy that hits an area) is important in maximizing the output of solar panels which absorb and convert this energy. To maximize output, factors such as the geographic location of solar panels and orientation can be determined by understanding insolation values.[5]

Importance

It is important to have values for insolation at certain positions on the Earth as these figures are used to help determine the size and output of solar power systems. Values for insolation can help to determine the expected output for solar panels and determine where on Earth solar panels would be most effective.[5]

As well, insolation is an important consideration in construction. When constructing a building in a particular climate, it is important to understand what the temperature and insolation will be like to ensure maximum comfort and energy efficient building design.

For Further Reading

References

  1. Alternative Energy. (August 4, 2015). What is Insolation? [Online]. Available: http://www.altenergy.org/Glossary/insolation.html
  2. angle the sun makes with the perpendicular of the surface
  3. A.Watson, D.Watson. (August 5, 2015). Insolation [Online]. Available: http://www.ftexploring.com/solar-energy/insolation.htm
  4. Wikimedia Commons. (August 4, 2015). Insolation [Online]. Available: https://commons.wikimedia.org/wiki/File:Insolation.png
  5. 5.0 5.1 Solar Insolation. (August 6, 2015). Solar Insolation [Online]. Available: http://solarinsolation.org/