Metabolic Rate in UTCI

Hi @chris,
How metabolic rate is being accounted for in Outdoor comfort components for both Ladybug and Honeybee? Is it not possible for these component to use BodyCharacteristics output of the Ladybug_Body Characteristic component?

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I remember the UTCI is calculated with walking condition (4kw/h). But it is part of UTCI definition I believe. I am also interested in if we can change this condition.

Indeed. Simulating outdoor comfort for metabolic conditions apart from a person walking would be very helpful. I think this is one of the shortcomings of the UTCI metric, along with clothing, which has been baked into the UTCI equation based on large sampling of individuals in outdoor conditions. There is much to improve upon with the UTCI metric and I haven’t had the chance to crack open the code for it. I know there are a few graduate students studying outdoor comfort on this forum that may be able to contribute.

@devang and @KitElsworth ,

@MingboPeng 's answer is correct. The UTCI model assumes typical walking metabolic rates and adaptive clothing based on observations of attire in the outdoors.

The desire to expose more parameters about the human body is why the Physiological Equivalent Temperature (PET) comfort model was created. So I suggest you use the PET model if you want an alternative to UTCI that accounts for metabolic rate. And conveniently, the PET model is why @djordje added the Ladybug_Body Characteristic component so you can use this component with that model.

You will see that there is also an option of a PET microclimate map recipe, which is meant for these situations.

I will say that, after coming to an understanding of how difficult it is to precisely measure clothing insulation and metabolic rate and how much error you can introduce when you make incorrect assumptions about them, I have gained an appreciation for the fact that these parameters are essentially adjusted for you in the UTCI and adaptive thermal comfort models. In other words, I often found that my own assumptions about metabolic rate and clothing are less accurate than those that are indirectly baked into the adaptive thermal comfort model. Still, there are cases where we know that the metabolic rate differs significantly from the assumptions in these models and, for this reason, human energy balance models like PET and PVM are still really important.