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<p class="MsoNormal">Hello everyone,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have a question concerning the validity of the solar data in the FI-Helsinki-Airport-29740.tm2 weather file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">After running my simulation with a typical year of Helsinki weather, I got the following errors concerning solar data:
<o:p></o:p></p>
<p class="MsoNormal"><i>“The calculated total horizontal radiation exceeded the horizontal extraterrestrial radiation and was set to the extraterrestrial for 1212 timesteps during the simulation”<o:p></o:p></i></p>
<p class="MsoNormal"><i>“The calculated horizontal beam radiation exceeded the provided total horizontal radiation and was set to the total horizontal radiation for 4 timesteps during the simulation”<o:p></o:p></i></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">To get the typical solar data for Helsinki, I modified the global horizontal, direct normal and diffuse horizontal solar data in the tm2 file (according to:
<i><span style="font-family:"Arial","sans-serif"">Development of weighting factors for climate variables for selecting the energy reference year according to the EN ISO 15927-4 standard.
</span></i><span lang="FI" style="font-family:"Arial","sans-serif"">Kalamees, T., Jylhä, K., Tietäväinen, H., Jokisalo, J., Ilomets, S., Hyvönen, R. and Saku, S.</span><span lang="FI" style="font-family:"Arial","sans-serif""> Vols.
</span><span style="font-family:"Arial","sans-serif"">Energy and Buildings 47 (2012) 53–60.</span>), leaving the extraterrestrial data untouched.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I found out that one reason behind the errors was that the extraterrestrial solar data do not seem to be valid. For example, in the tm2 file, there are only 5 hours of extraterrestrial solar data for the shortest days of the year. In reality
however, the minimum daylight hours is just under 6 hours…<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So my question is, does anyone know of a valid method to circumvent this inconsistent extraterrestrial data problem? Can I simply set all of the extraterrestrial radiation values to a high number throughout the year (and how useful are
these if non-extraterrestrial radiation data are already provided)?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you for your help,<o:p></o:p></p>
<p class="MsoNormal">Ciarán<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">----------------------------------------<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Ciarán Flynn<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Project Researcher<o:p></o:p></span></i></p>
<p class="MsoNormal" style="margin-top:6.0pt"><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Aalto University - Department of Energy Technology<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span lang="FI" style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">P.O.Box 14100, 00076 Aalto<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span lang="FI" style="font-size:10.0pt;font-family:"Arial","sans-serif";color:black">Otakaari 4, 02150 ESPOO<o:p></o:p></span></i></p>
<p class="MsoNormal"><span lang="FI"><o:p> </o:p></span></p>
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