After being quest to plunk into photovoltaic charge card greenhouses , Nicolas Julien , R&D Engineer at Filclair , rapidly reason out placing solar panel on top of a fictile greenhouse would not work as the systems would be too heavy for the construction . However , there are opportunities to turn solar light into electricity within a credit card greenhouse , recent enquiry shows : by localise solar panels inside the greenhouse , underneath the gutter . Vertically , that is . A simulation exhibit it could concentrate the final heating disbursal of a nursery to about 50,000 euros per year per hectare .
" Photovoltaic solar panels are increasingly being integrate into the agricultural sphere , and we were consulted to respond to asking for photovoltaic greenhouses , " read Nicolas . " But the structure of plastic glasshouse is not unassailable enough to support solar panels on the ceiling . Therefore , it was necessary for Filclair to seek to find oneself other solution to meet this PV greenhouse market . "
With the diffusion coefficient from the plastic photographic film manufacturer in mind , and simulations from the European official system PVJJS , which provides geographical information on photovoltaics , he explore various ways to set the panels inside the greenhouse . When it come to solar panels , position is critical . « A restore dialog box tilted at an optimal slant of 39 ° towards the South find +18 % more light throughout the twelvemonth than a horizontal panel , and a perpendicular bifacial dialog box receives +15 % on both sides . When using East - West solar trailing , the light profit is +40 % » , Nicolas says , but the idea of a trailing organisation in the greenhouse was abandoned as the diffusion of visible radiation significantly cut the interest in tracking .
Therefore , the team focus on a conformation that would take maximal advantage of the benefits of diffuse illumination , which are to eliminate the risk of shading and to be capable to place the instrument panel with the want orientation course without casting a direct shadow on the crop : placing them vertically , under the trough . By using bifacial panels and produce use of the reflexion potentiality of greenhouses and its interior , he sees electric potential as the higher amount of diffuse light inside the greenhouse compensates for the 20 % going of luminosity due to the glasshouse cover and social organisation . " But the higher the panel , the less good the diffuse visible radiation becomes because of the going of igniter . "
So how about the number ? " For a total surface area of 1170 m² of bifacial panels ( 2340 m² of photocells ) for a greenhouse of 9600 m² ( 10 spans of 9.60 m x 100 m ) , one can have a bun in the oven the biface venire to capture up to 128 % of the amount of luminosity captured by an equivalent horizontal surface outside " , Nicolas concludes from simulations , seize the mediocre albedo of the greenhouse floor ( include the crops ) was 50 % , and the ETFE plastic films have both excellent light transmittal and dear weak diffusion . " When stacking 2 panel to repeat the stature of each row , there is still more light compared to the remote solar beam . By tripling the height , it is less advantageous , but we still retain 89 % of the international Global Horizontal solar shaft of light " , he conclude .
allot to Nicholas , the fact that there is a maximum of diffuse light in the nursery is not only beneficial for the panel but also for the vegetation , allow for very homogenous lighting and no shadow from the panels . " Moreover , the panels are located in a view that does not interfere with activities inside the greenhouse . It can be assumed that the decrease in production due to the overall decrease in luminosity in the nursery can be partly compensated by this more homogeneous light on the leaves , make it more profitable than a traditional photovoltaic nursery with panels placed on the roof , " he says .
He does say there is additional information to take into chronicle , such as the higher cost of bifacial solar panels and the essence of the high temperature in the greenhouse on the efficiency of the panels . " Conducting genuine - humankind experiment is essential to validate these hypotheses and gather more information on the performance and efficiency of bifacial solar panels under ETFE nursery . It would also allow us to study the effect of different factors such as temperature , humidity , and weather conditions on the panels ' performance . "
To put these results in view and focalize on a specific display case , Nicolas come to to the study by Agrithermic using the Hortinergy computer software , which demonstrated that a Filclair double - inflated ETFE greenhouse could gain from +18 % more luminosity than a Venlo glass greenhouse . If nine wrangle of vertical biface panels were install under this ETFE greenhouse at the summit of 1.3 meter , the decrement in luminousness due to the panel would on the dot compensate for this surplus of +18 % of light under the ETFE greenhouse , thus keep farming output with additional Energy Department output . " For a one - hectare greenhouse of tomatoes , with double ETFE inflatable cover and a thermal filmdom , take on an energy price of 40 euros / MWh for gas , heat disbursal would be around 80,000 euros per year by heating the glasshouse at 20 ° degree Celsius during the solar day and 16 ° nose candy at night throughout the twelvemonth except in November . The photovoltaic system would reduce the net warming expenses of such a nursery to about 50,000 euro per yr per hectare . "
Of course , to arrive at a true expulsion of electric production for this specific configuration , experiments would need to be conduct in the field to address proficient precariousness , such as the warming of the dialog box inside the nursery . " A more in - astuteness techno - economical analysis establish on substantial - life conditions would therefore be essential to progress a executable economic mannikin for these comparatively unexampled agrivoltaic greenhouse . yet , the purpose of bifacial solar panels in glasshouse has the potential to provide multiple benefits such as increased energy yield , improved harvest take , and reduced environmental encroachment . "
For more information : Jelle BoetersFilclairTel . : +31 623 141 992Email:[email protected][email protected]www.filclair.com
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