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<span>Hi everyone,</span></div>
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I have set up a very simple solar project: just 2 components:</div>
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<li>a weather processor type 15</li></ul>
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<li>a solar collect or type 1b (with 1 m2 area).</li></ul>
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<div>The collector tracks the sun (mode 3) with rotation axis N-S and makes use only of the beam radiation.</div>
<div>Efficiency as function of mean temperature (mode 2).<br>
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<div>I get weird results that make me doubt that Type 1b works as it should.<br>
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<div><span style="font-family: Calibri, Helvetica, sans-serif; background-color: rgb(255, 255, 255); display: inline !important">The model is exactly the same every time, but I change the heat loss coefficients (a1 and a2) of the collector.</span><br>
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<div>When both a1 and a2 are 0.0001, the useful output (as returned by type 1) is 4.43E+06 kJ/m2/year. </div>
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<div>When a1 is 0.0001, and a2 is 0, the useful output drops unrealistically to to 3.99E+06 kJ/m2/year. </div>
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<div>The second results is in agreement (just 0.04% off) with the yearly sum of the quantity<br>
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<div>Gb * IAM * eta0<br>
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<div>where<br>
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<div>Gb is the beam radiation on the surface (i only consider beam component)<br>
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<div>IAM is the incidence angle modifier<br>
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<div>eta0 is the peak collector efficiency.<br>
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<div>However, when i set the heat loss coefficients to their actual values, the yearly energy output from type 1b is not the sum over the year of the quantity:</div>
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<div><span style="font-family: Calibri, Helvetica, sans-serif; background-color: rgb(255, 255, 255); display: inline !important">Gb * IAM * eta0 - a1*DT - a2*DT^2</span></div>
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<div><span style="font-family: Calibri, Helvetica, sans-serif; background-color: rgb(255, 255, 255); display: inline !important">but it is about 11% off...</span></div>
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<div>If someone has also had problems with type 1 and got to make it work, it would be great to hear
<span id="🙂">🙂</span></div>
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<div>Thanks in advance and best regards,<br>
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<span>Federico</span><br>
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