Total/Opaque Sky Cover (tenths) vs Cloudiness (octa) - Unmet Hours

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Total/Opaque Sky Cover (tenths) vs Cloudiness (octa)

asked 4 years ago

flag of Belgium

207 ●1 ●6 http://www.cenaero.be/

updated 4 years ago

flag of United States of America

14375 ●90 ●25 http://bigladdersoftware.com/

Hi everyone,

In my actual weather data, I don't have Horizontal Infrared Radiation Intensity but cloudiness, whose unit is octa (i.e. 1 is 1/8). From Energyplus documentation, I saw that the Horizontal Infrared Radiation Intensity can be calculated from the Opaque Sky Cover, whose unit is tenths (i.e. 1 is 1/10 covered, 10 is total coverage). Could someone tell me please if the cloudiness in actual weather data corresponds to the Opaque Skey Cover in EPW. If yes, Do I have to convert octa into tenth for the calculation of Horizontal Infrared Radiation Intensity?

Thank you very much for your help.

L. Lê

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answered 4 years ago

lklawrie
450 ●14 ●4

If the units are given as octas, then the cloudiness could be considered equivalent to sky cover after multiplying by 1.25.

With a proper definitions file, the Energyplus Weather Converter can also do that for you.

Linda

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Thank you very much for your answer.

vlle ( 4 years ago )

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Asked: 4 years ago

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Last updated: Apr 19 '21

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