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<p>Sam,</p>
<p> You are certainly correct that covering a roof with PV panels
will change the roof temperature. There are also impacts of how
much (if any) air flows between the panels and the roof and at
times, the PVs can radiate to the night sky and provide some
cooling to the roof.</p>
<p> If you are using one of the standard PV models in TRNSYS then
you won't see any impact. Those PV models just compute electrical
output. They don't deal with any thermal impact that the array has
on its surroundings. If you need to estimate the impact of the PV
panels on the roof, you'll need to use one of the BIPV components
in the TESS Electrical library to model the PV.</p>
<p>kind regards,</p>
<p> David</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 02/12/2020 11:19, Sam Elyas via
TRNSYS-users wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAJDXPtXPPWOjp6GrZ1gUiceRYRqLjfJxViX+1NAuVLOO21BuPQ@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">Dear community,<br>
<div><br>
</div>
<div>I'm wondering if the roof of the building I'm modelling is
70% covered of PV panels increases roof's temperature,</div>
<div><br>
</div>
<div>Let's assume 20% of solar energy is converted to
electricity, the remaining 80% is thermal energy stored in the
PV panels as heat and transmitted to the roof and the sky,
thus increasing roof's temperature compared to a low
absorption roof coating (cool roof without </div>
<div>PV panels) ? am I getting this wrong ?</div>
<div><br>
</div>
<div>Thank you!</div>
</div>
<br>
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<pre class="moz-signature" cols="72">--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
3 North Pinckney Street - suite 202
Madison, WI 53703 USA
P:+1.608.274.2577
F:+1.608.278.1475
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