<span class="mw-page-title-main">Solar thermal collector</span>

Solar thermal collector

<p>A <b>solar thermal collector</b> collects <a href="/en/Heat" title="Heat" class="wl">heat</a> by <a href="/en/Absorption_(optics)" title="Absorption (optics)" class="mw-redirect wl">absorbing</a> <a href="/en/Sunlight" title="Sunlight" class="wl">sunlight</a>. The term "solar collector" commonly refers to a device for <a href="/en/Solar_hot_water_panel" title="Solar hot water panel" class="mw-redirect wl">solar hot water heating</a>, but may refer to large power generating installations such as <a href="/en/Solar_parabolic_trough" title="Solar parabolic trough" class="mw-redirect wl">solar parabolic troughs</a> and <a href="/en/Solar_power_tower" title="Solar power tower" class="wl">solar towers</a> or non <a href="/en/Water" title="Water" class="wl">water</a> heating devices such as <a href="/en/Solar_cooker" title="Solar cooker" class="wl">solar cooker</a>, <a href="/en/Solar_air_heat" title="Solar air heat" class="wl">solar air heaters</a>.<span class="mw-ref reference" id="cite_ref-1"><a href="#cite_note-1" style="counter-reset: mw-Ref 1;"><span class="mw-reflink-text">[1]</span></a></span></p>

<div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none" about="#mwt1">Device that collects heat</div>
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<figure class="mw-default-size wiki-thumb"><a href="/en/File:Solar_panels,_Santorini2.jpg" class="mw-file-description image media-thumb" data-hash="File:Solar_panels,_Santorini2.jpg"><img loading="lazy" alt="Solar_panels%2C_Santorini2.jpg" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Solar_panels%2C_Santorini2.jpg/220px-Solar_panels%2C_Santorini2.jpg" decoding="async" data-file-width="800" data-file-height="600" data-file-type="bitmap" height="165" width="220" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Solar_panels%2C_Santorini2.jpg/330px-Solar_panels%2C_Santorini2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Solar_panels%2C_Santorini2.jpg/440px-Solar_panels%2C_Santorini2.jpg 2x"></a><figcaption>Water heating system deployed on a flat roof. The pipes that carry the heat away can be seen embedded in the absorber, a flat plate painted black. In this example the heat is stored in the tank above the panels.</figcaption></figure>
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<p>Solar thermal collectors are either non-concentrating or concentrating. In non-concentrating collectors, the aperture area (i.e., the area that receives the <a href="/en/Solar_radiation" title="Solar radiation" class="mw-redirect wl">solar radiation</a>) is roughly the same as the absorber area (i.e., the area absorbing the radiation). A common example of such a system is a metal plate that is painted a dark color to maximize the absorption of sunlight. The energy is then collected by cooling the plate with a <a href="/en/Working_fluid" title="Working fluid" class="wl">working fluid</a>, often water or <a href="/en/Glycol" title="Glycol" class="mw-redirect wl">glycol</a> running in pipes attached to the plate.</p>

<p>Concentrating collectors have a much larger aperture than the absorber area. The aperture is typically in the form of a <a href="/en/Mirror" title="Mirror" class="wl">mirror</a> that is focussed on the absorber, which in most cases are the pipes carrying the working fluid.<span class="mw-ref reference" id="cite_ref-2"><a href="#cite_note-2" style="counter-reset: mw-Ref 2;"><span class="mw-reflink-text">[2]</span></a></span> Due to the movement of the sun during the day, concentrating collectors often require some form of solar tracking system, and are sometimes referred to "active" collectors for this reason.</p><p>

Non-concentrating collectors are typically used in residential, industrial and commercial buildings for <a href="/en/Space_heating_and_cooling" title="Space heating and cooling" class="mw-redirect wl">space heating</a>, while concentrating collectors in <a href="/en/Concentrated_solar_power" title="Concentrated solar power" class="wl">concentrated solar power</a> plants generate <a href="/en/Electricity" title="Electricity" class="wl">electricity</a> by heating a heat-transfer fluid to drive a <a href="/en/Turbine" title="Turbine" class="wl">turbine</a> connected to an <a href="/en/Electrical_generator" title="Electrical generator" class="mw-redirect wl">electrical generator</a>.<span class="mw-ref reference" id="cite_ref-3"><a href="#cite_note-3" style="counter-reset: mw-Ref 3;"><span class="mw-reflink-text">[3]</span></a></span></p><style data-mw-deduplicate="TemplateStyles:r886046785" typeof="mw:Extension/templatestyles mw:Transclusion">.mw-parser-output .toclimit-2 .toclevel-1 ul,.mw-parser-output .toclimit-3 .toclevel-2 ul,.mw-parser-output .toclimit-4 .toclevel-3 ul,.mw-parser-output .toclimit-5 .toclevel-4 ul,.mw-parser-output .toclimit-6 .toclevel-5 ul,.mw-parser-output .toclimit-7 .toclevel-6 ul{display:none}</style><div class="toclimit-3" about="#mwt25"><meta property="mw:PageProp/toc"></div> 



A solar thermal collector collects heat by absorbing sunlight. The term "solar collector" commonly refers to a device for solar hot water heating, but may refer to large power generating installations such as solar parabolic troughs and solar towers or non water heating devices such as solar cooker, solar air heaters. Solar thermal collectors are either non-concentrating or concentrating. In non-concentrating collectors, the aperture area is roughly the same as the absorber area . A common example of such a system is a metal plate that is painted a dark color to maximize the absorption of sunlight. The energy is then collected by cooling the plate with a working fluid, often water or glycol running in pipes attached to the plate. Concentrating collectors have a much larger aperture than the absorber area. The aperture is typically in the form of a mirror that is focussed on the absorber, which in most cases are the pipes carrying the working fluid. Due to the movement of the sun during the day, concentrating collectors often require some form of solar tracking system, and are sometimes referred to "active" collectors for this reason. 