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architecture-building-systems / sia_380-1-full_version

This code is the python implemented form of SIA380-1. It is not a simplified version.
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Embodied system calculation monthly vs. hourly quite large difference (about 30%) #109

Closed kuhnal closed 3 years ago

kuhnal commented 4 years ago

Is that difference only due to the calculation approach or is there a mistake in the calculation somewhere? Monthly values seem to agree more with values derived by Wyss et al. I need to look further into this.

kuhnal commented 3 years ago

Base Case: nom. heating power monthly: 61.74kW nom. heating power hourly: 65.6kW nom. cooling power monthly: 29.7kW nom. cooling power hourly: -100.5kW

Seems that the hourly cooling power calculation is a bit off. It actually is the source of the problem! Screenshot 2020-12-02 at 14 25 09

kuhnal commented 3 years ago

@Linwal did this problem also occur to you at one point? The base case I tested is a very "normal" building with quite good insulation (Minergie P Eco), but other than the building envelope nothing special.

Linwal commented 3 years ago

@Linwal did this problem also occur to you at one point? The base case I tested is a very "normal" building with quite good insulation (Minergie P Eco), but other than the building envelope nothing special.

Yes, I also had deviations. The graph shows kgCO2-eq per annum per m2. So far I have not spent any time in futher investigating it though.

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The issue with the cooling power is actually one that I could not solve yet. While there are several simplified methods to dimension a heating system based on monthly values, I did not find one that can be used for cooling. That's why the monthly calculation is currently based on SIA2024. @kuhnal maybe you know an approach? On the other side, the cooling system is currently dimensioned to be able to bring the needed power for each hour of the year. Maybe taking the 80% quantile or a similar approach would make sense. Otherwise it seems to be overdimensioned quite a bit.

--> see simulation_engine_dynamic.py, run_cooling_sizing()

@Linwal : fix this (probably not before Christmas)

kuhnal commented 3 years ago

The issue with the cooling power is actually one that I could not solve yet. While there are several simplified methods to dimension a heating system based on monthly values, I did not find one that can be used for cooling. That's why the monthly calculation is currently based on SIA2024. @kuhnal maybe you know an approach?

I also wasn't able to find an approach for the monthly calculation of the cooling load.. Also the book that I showed you a few weeks ago (by the way, here is the link to it: https://enbau-online.ch/heizung-lueftung-elektrizitaet/), only refers to the calculation based on SIA 2044 and 382/2 (--> ISO 52016).