Solar PV in hot climate zones - Revision history

Till Serafimov at 11:37, 21 August 2019

2019-08-21T11:37:41Z

Ranisha at 11:17, 25 April 2019

2019-04-25T11:17:44Z

Lisafeldmann at 13:00, 16 April 2019

2019-04-16T13:00:33Z

Till Serafimov: /* Solar panel related considerations */

2019-03-19T02:39:11Z

‎Solar panel related considerations

Till Serafimov: /* Solar panel related considerations */

2019-03-19T02:36:39Z

‎Solar panel related considerations

Till Serafimov at 02:35, 19 March 2019

2019-03-19T02:35:54Z

Till Serafimov at 02:26, 19 March 2019

2019-03-19T02:26:20Z

Till Serafimov: /* Solar panel related considerations */

2019-03-19T02:11:38Z

‎Solar panel related considerations

Johanna at 13:48, 8 March 2019

2019-03-08T13:48:08Z

Johanna at 13:46, 8 March 2019

2019-03-08T13:46:26Z

Show changes

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 = Design considerations and technological options for solar PV systems in hot climatic zones<br/> =
@@ Line 5: / Line 6: @@
 == Background<br/> ==
-Since 2009, GIZ [https://endev.info/content/Ethiopia Energising Development Ethiopia] (EnDev ET) has been installing stand-alone solar PV systems of different sizes (between 300 and 2.400Wp) for social institutions [[Ethiopia Energy Situation|all over the country]].
+Since 2009, GIZ [https://endev.info/content/Ethiopia Energising Development Ethiopia] (EnDev ET) has been installing stand-alone solar PV systems of different sizes (between 300Wp and 2.400Wp) for social institutions [[Ethiopia Energy Situation|all over the country]].
 Most of these 300+ installed solar systems are located in the highlands or sub-tropic zones that feature moderately-warm temperatures that are ideal for the uninterrupted operation of these systems. In the north-western (Afar) and south-western (Somali) regions of the country, however, scorching sun meets hot desert climate, with average annual temperatures around 30°C (86°F) and peak temperatures reaching easily above 40°C (104°F). These circumstances inspired the redaction of the present article that attempts to compile different responses regarding system design and technical components to extreme air temperatures.
@@ Line 23: / Line 24: @@
 Given the effects of high temperatures on the solar module output, there are ways to mitigate this effect through the right installation of the panels:<ref name="https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies">https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies</ref>
 <ul style="list-style-type:circle;">
-<li>Panels should be installed on the roof or another carrier with enough of space for airflow on the back of the modules to cool down the modules.</li>
+<li>Panels should be installed on the roof or another carrier with enough of space for airflow on the back of the modules to cool down the modules. The PV-mounting manufacturer Renusol has recently presented a mounting system for metal roofs that is designed for hot regions in particular. According to the manufacturer, this system leaves around 10 centimetres between the solar panel and the roof, hence allowing for increased airflow, and decreasing the panel output losses by up to 5%.<ref>https://www.renusol.com/en/service/news-press/press-release/article/435-new-products-at-intersolar-europe-cologne-based-manufacturer-renusol-to-present-a-universal-clam.html</ref>&nbsp; </li>
 <li>Heat absorption may also be reduced if the panels are installed on and next to light-coloured material.</li>
 </ul>
@@ Line 210: / Line 211: @@
 The different electrochemical reactions of LiFePO-batteries to temperatures as compared to lead-acid batteries will also require an adjustment of the temperature-based voltage compensation of a charge controller, if not a LiFePO-specific charge controller is in use.
+<br/>
 = Conclusion =
@@ Line 237: / Line 238: @@
 </div><br/>
 [[Category:Batteries]]

@@ Line 1: / Line 1: @@
 = Design considerations and technological options for solar PV systems in hot climatic zones<br/> =
@@ Line 238: / Line 237: @@
 </div><br/>
 [[Category:Solar]]

@@ Line 1: / Line 1: @@
-= '''Design considerations and technological options for solar PV systems in hot climatic zones'''<br/> =
+= Design considerations and technological options for solar PV systems in hot climatic zones<br/> =
 <br/>
-== '''Background'''<br/> ==
+== Background<br/> ==
 Since 2009, GIZ [https://endev.info/content/Ethiopia Energising Development Ethiopia] (EnDev ET) has been installing stand-alone solar PV systems of different sizes (between 300 and 2.400Wp) for social institutions [[Ethiopia Energy Situation|all over the country]].
@@ Line 14: / Line 14: @@
 To start with, the article outlines the three main components, i.e. solar PV panels, inverters and batteries, to receive special attention when being used in hot climatic zones:
-&nbsp;<br/>
+&nbsp;
-−
-<br/>
-−
-−
-== '''Solar panel related considerations''' ==
+== Solar panel related considerations ==
 For those without a technical background in solar energy, it may seem counter-intuitive that solar PV panels face significant challenges when being used in areas with high levels of sun irradiation and increased air temperatures. Usually, PV modules are tested at a temperature of 25°C (77°F), but if the temperature of the solar panels increases, the voltage output decreases in direct correlation and linearly. This has significant effects on the output of solar panels -&nbsp; also in the case of Ethiopia, that features areas with high levels of solar irradiation (>2000 kWh/m² per year)<ref>https://globalsolaratlas.info/downloads/ethiopia</ref>. Under such conditions, temperatures within the solar module can reach up to 100°C (212°F). This reduction of the peak output of the solar panel for each 1°C is expressed with the Pmpp-coefficient that should be indicated at every solar PV panel datasheet. As example, a solar panel whose peak output is tested at 25°C and has a Pmpp co-efficient of 0.4% per degree Celsius will lose 30% of its output once the internal temperature reaches 100°C!<ref name="https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies">https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies</ref>
@@ Line 48: / Line 44: @@
 <br/>
 == Inverter related considerations ==
-== '''Inverter related considerations''' ==
 Inverters of reputed manufacturers (Outback, SMA, Victron etc.) can operate within temperatures up to 60-65℃. Their continuous AC-output, however, decreases with rising temperatures. Starting from the rated continuous AC-output at 25°C (77°F), the continuous output of inverters decreases for example at 40°C (104°F) by 6-15%, depending on the model.<ref name="Datasheets of different models under: https://www.victronenergy.com http://www.outbackpower.com/products/inverter-charger https://www.sma.de/en/products/battery-inverters">Datasheets of different models under: https://www.victronenergy.com http://www.outbackpower.com/products/inverter-charger https://www.sma.de/en/products/battery-inverters</ref>
@@ Line 59: / Line 54: @@
 &nbsp;
-== '''Battery related consideration''' ==
+== Battery related consideration ==
 Lead-acid batteries are still by default used in most larger solar PV systems across the world. Apart from their highly toxic content consisting mostly of lead, diverse lead compounds and acid, their lifetime is proven to decrease rapidly with increasing temperatures.&nbsp;
@@ Line 216: / Line 211: @@
 The different electrochemical reactions of LiFePO-batteries to temperatures as compared to lead-acid batteries will also require an adjustment of the temperature-based voltage compensation of a charge controller, if not a LiFePO-specific charge controller is in use.
-= '''Conclusion''' =
 The initial findings of this article allow for the conclusion on a couple of technological and installation-related adjustments in order to cope with high air temperatures around solar PV systems in hot climatic zones.
@@ Line 241: / Line 238: @@
 </div><br/>
 [[Category:Hot_climate]]

@@ Line 17: / Line 17: @@
 <br/>
@@ Line 37: / Line 38: @@
 *Hybrid version available that includes a thermal collector for absorbing parts of the heat.&nbsp;
-Also the solar panel producer Almaden ([https://www.almaden-europe.com https://www.almaden-europe.com]) offers heavy-duty panels that are
+Also the solar panel producer Almaden ([https://www.almaden-europe.com https://www.almaden-europe.com]) offers heavy-duty panels that feature
-*Extremely heat resistant through double-glas design
+*Extreme heat resistance because of their double-glas design
-*Free of PID-related losses
+*No PID-related losses
 *Bifacial design that enables the panels to capture background reflected light and peripheral scattered light

@@ Line 17: / Line 17: @@
 <br/>
 == '''Solar panel related considerations''' ==
-For those without a technical background in solar energy, it may seem counter-intuitive that solar PV panels face significant challenges when being used in areas with high levels of sun irradiation and increased air temperatures. Usually, PV modules are tested at a temperature of 25°C (77°F), but if the temperature of the solar panels increases, the voltage output decreases in direct correlation and linearly. This has significant effects on the output of solar panels -&nbsp; also in the case of Ethiopia, that features areas with high levels of solar irradiation (>2000 kWh/m² per year)<ref>https://globalsolaratlas.info/downloads/ethiopia</ref>. Under such conditions temperatures within the solar module can reach up to 100°C (212°F). This reduction of the peak output of the solar panel for each 1°C is expressed with the Pmpp-coefficient that should be indicated at every solar PV panel datasheet. As example, a solar panel whose peak output is tested at 25°C and has a Pmpp co-efficient of 0.4% per degree Celsius will lose 30% of its output once the internal temperature reaches 100°C!<ref name="https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies">https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies</ref>
+For those without a technical background in solar energy, it may seem counter-intuitive that solar PV panels face significant challenges when being used in areas with high levels of sun irradiation and increased air temperatures. Usually, PV modules are tested at a temperature of 25°C (77°F), but if the temperature of the solar panels increases, the voltage output decreases in direct correlation and linearly. This has significant effects on the output of solar panels -&nbsp; also in the case of Ethiopia, that features areas with high levels of solar irradiation (>2000 kWh/m² per year)<ref>https://globalsolaratlas.info/downloads/ethiopia</ref>. Under such conditions, temperatures within the solar module can reach up to 100°C (212°F). This reduction of the peak output of the solar panel for each 1°C is expressed with the Pmpp-coefficient that should be indicated at every solar PV panel datasheet. As example, a solar panel whose peak output is tested at 25°C and has a Pmpp co-efficient of 0.4% per degree Celsius will lose 30% of its output once the internal temperature reaches 100°C!<ref name="https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies">https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies</ref>
 Moreover, high temperatures can foster the “Potential-Induced Degradation” (PID) that is typical for most crystalline solar modules and results in so-called leakage currents that flow through the embedded parts and the backside of the module. These leakage currents foster electrochemical corrosion within the module and can significantly reduce its performance too.<ref>https://www.jvg-thoma.de/en/photovoltaic-technology/desert-technology/high-temperature-resistance/</ref>
@@ Line 42: / Line 43: @@
 *Bifacial design that enables the panels to capture background reflected light and peripheral scattered light
 It is assumed that the costs of these special panels are higher than those of standard panels. It was, however, not possible to obtain pricing information at the time of redaction of this article.
 <br/>
 == '''Inverter related considerations''' ==

@@ Line 36: / Line 36: @@
 *Hybrid version available that includes a thermal collector for absorbing parts of the heat.&nbsp;
-Also Almaden ()
+Also the solar panel producer Almaden ([https://www.almaden-europe.com https://www.almaden-europe.com]) offers heavy-duty panels that are
-It is assumed that the costs of these special panels are higher than those of standard panels. The supplier, however, did not the pricing information on request to date.
+*Extremely heat resistant through double-glas design
 <br/>
@@ Line 56: / Line 60: @@
 Lead-acid batteries are still by default used in most larger solar PV systems across the world. Apart from their highly toxic content consisting mostly of lead, diverse lead compounds and acid, their lifetime is proven to decrease rapidly with increasing temperatures.&nbsp;
-The nowadays commonly used sealed, maintenance free gel-batteries (VLRA-type) can easily reach lifetimes of 10+ years under temperatures at 25°C (77°F).<ref name="https://batteryuniversity.com/learn/article/how_heat_and_harsh_loading_reduces_battery_life">https://batteryuniversity.com/learn/article/how_heat_and_harsh_loading_reduces_battery_life</ref> However, rising temperatures have significant effects on the electrochemical activities within the lead-acid battery, increasing on the one hand its capacity, but decreasing on the other hand the voltage output due to higher resistance and band gap that are caused within the battery with rising temperatures.<ref>https://prezi.com/wafnvrdsvsa2/how-does-temperature-affect-voltage-and-life-of-battery/</ref> Furthermore, increased cell temperatures lead to higher electrochemical activities that foster corrosion within the battery, hence diminishing the battery capacity and its total lifetime in the long run.<ref>https://www.sciencedirect.com/science/article/pii/S0306261918310225</ref>&nbsp;&nbsp;
+The nowadays commonly used sealed, maintenance free gel-batteries (VLRA-type) can easily reach lifetimes of 10+ years under temperatures at 25°C (77°F) but only if any deep discharge of less than 45% is avoided.<ref name="https://batteryuniversity.com/learn/article/how_heat_and_harsh_loading_reduces_battery_life">https://batteryuniversity.com/learn/article/how_heat_and_harsh_loading_reduces_battery_life</ref> Furthermore, rising temperatures have significant effects on the electrochemical activities within the lead-acid battery, increasing on the one hand its capacity, but decreasing on the other hand the voltage output due to higher resistance and band gap that are caused within the battery with rising temperatures.<ref>https://prezi.com/wafnvrdsvsa2/how-does-temperature-affect-voltage-and-life-of-battery/</ref> Furthermore, increased cell temperatures lead to higher electrochemical activities that foster corrosion within the battery, hence diminishing the battery capacity and its total lifetime in the long run.<ref>https://www.sciencedirect.com/science/article/pii/S0306261918310225</ref>&nbsp;&nbsp;
 The prospected decrease in lifetime for different battery types illustrated below:<ref>https://prevent-germany.com/prevent-blog/batterien-im-detail</ref>
@@ Line 234: / Line 238: @@
 </div><br/>
 [[Category:Solar]]

@@ Line 15: / Line 15: @@
 &nbsp;<br/>
 == '''Solar panel related considerations''' ==
-For those without a technical background in solar energy, it may seem counter-intuitive that solar PV panels face significant challenges when being used in areas with high levels of sun irradiation and increased air temperatures. Usually, PV modules are tested at a temperature of 25°C (77°F), but if the temperature of the solar panels increases, the voltage output decreases in direct correlation and linearly. This has significant effects on the output of solar panels -&nbsp; even in areas with medium levels of solar irradiation (around 2000 kWh/m²) where temperatures within the solar module can reach up to 100°C (212°F). This reduction of the peak output of the solar panel for each 1°C is expressed with the Pmpp-coefficient that should be indicated at every solar PV panel datasheet. As example, a solar panel whose peak output is tested at 25°C and has a Pmpp co-efficient of 0.4% will lose 25% of its output once the internal temperature reaches 100°C!<ref name="https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies">https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies</ref>
+For those without a technical background in solar energy, it may seem counter-intuitive that solar PV panels face significant challenges when being used in areas with high levels of sun irradiation and increased air temperatures. Usually, PV modules are tested at a temperature of 25°C (77°F), but if the temperature of the solar panels increases, the voltage output decreases in direct correlation and linearly. This has significant effects on the output of solar panels -&nbsp; even in areas with medium levels of solar irradiation (around 2000 kWh/m²) where temperatures within the solar module can reach up to 100°C (212°F). This reduction of the peak output of the solar panel for each 1°C is expressed with the Pmpp-coefficient that should be indicated at every solar PV panel datasheet. As example, a solar panel whose peak output is tested at 25°C and has a Pmpp co-efficient of 0.4% will lose 30% of its output once the internal temperature reaches 100°C!<ref name="https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies">https://www.civicsolar.com/support/installer/articles/how-does-heat-affect-solar-panel-efficiencies</ref>
 Moreover, high temperatures can foster the “Potential-Induced Degradation” (PDI) that is typical for most crystalline solar modules and results in so-called leakage currents that flow through the embedded parts and the backside of the module. These leakage currents foster electrochemical corrosion within the module and can significantly reduce its performance too.<ref>https://www.jvg-thoma.de/en/photovoltaic-technology/desert-technology/high-temperature-resistance/</ref>
@@ Line 35: / Line 36: @@
 It is assumed that the costs of these special panels are higher than those of standard panels. The supplier, however, did not the pricing information on request to date.
 == '''Inverter related considerations''' ==

@@ Line 6: / Line 6: @@
 == '''Background'''<br/> ==
-Since 2009, GIZ [https://endev.info/content/Ethiopia Energising Development Ethiopia] (EnDev ET) has been installing stand-alone solar PV systems of different sizes (between 300 and 2.400Wp) for social institutions [[Ethiopia_Energy_Situation|all over the country]].
+Since 2009, GIZ [https://endev.info/content/Ethiopia Energising Development Ethiopia] (EnDev ET) has been installing stand-alone solar PV systems of different sizes (between 300 and 2.400Wp) for social institutions [[Ethiopia Energy Situation|all over the country]].
 Most of these 300+ installed solar systems are located in the highlands or sub-tropic zones that feature moderately-warm temperatures that are ideal for the uninterrupted operation of these systems. In the north-western (Afar) and south-western (Somali) regions of the country, however, scorching sun meets hot desert climate, with average annual temperatures around 30°C (86°F) and peak temperatures reaching easily above 40°C (104°F). These circumstances inspired the redaction of the present article that attempts to compile different responses regarding system design and technical components to extreme air temperatures.
@@ Line 217: / Line 217: @@
 = Further Information =
-*[[Photovoltaic_(PV)|Photovoltaic_(PV)]]
+*[[Photovoltaic (PV)|Photovoltaic_(PV)]]
 *[[Batteries|Batteries]]
-*[[End-of-Life_Management_of_Batteries_in_the_Off-Grid_Solar_Sector|End-of-Life Management of Batteries in the Off-Grid Solar Sector]]
+*[[End-of-Life Management of Batteries in the Off-Grid Solar Sector|End-of-Life Management of Batteries in the Off-Grid Solar Sector]]
-*[[Recycling_of_Photovoltaic_(PV)_Batteries|Recycling of Photovoltaic (PV) Batteries]]
+*[[Recycling of Photovoltaic (PV) Batteries|Recycling of Photovoltaic (PV) Batteries]]
 = References<br/> =
@@ Line 227: / Line 228: @@
 </div><br/>
 [[Category:Solar]]