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ladybug-tools / epwmap

⛅️ map of available .epw weather files
http://ladybug-tools.github.io/epwmap/
MIT License
33 stars 18 forks source link

Add Heating / Cooling Design Day Temperatures #18

Open chriswmackey opened 7 years ago

chriswmackey commented 7 years ago

Th is issue is continuing what @alemenchaca started here: https://github.com/mostaphaRoudsari/epwmap/issues/1

Namely, it would be great if the summary that pops up when you scroll over EPW files displayed the heating/cooling design day temperatures that are typically used to size HVAC systems and understand the coldest and warmest temperatures of a given climate. The usual way that these design temperatures are derived is by taking a temperature that represents 1 percentile of the coldest and warmest possible times of the year (since it's usually not reasonable to take the coldest temperature ever recorded in a given climate). Sometimes a 0.4 percentile is also used if a HVAC engineer needs to be particularly conservative. I'm imagining these values going right below the hours of outdoor comfort on the map: epwmap proposal

Usually the easiest way to get these design temperatures is to pull them from the .stat file and I have highlighted where they are located here: designtemperatures

@mostaphaRoudsari , you can also calculate these values from analysis of the EPW data by sorting all dry bulb temperatures and then taking the 88th temperature for the 1% design day condition (since 8760 x 1% = 87.6) but the stat file method above is more accurate.

Let me know if you need help bringing this to fruition.

mostaphaRoudsari commented 7 years ago

Hi @chriswmackey and @alemenchaca. This takes another round of parsing the data which won't take much work. In the future I think this will be part of an abstract report that should be generated for each station.

@chriswmackey based on the image you're looking for the 99.6 and 0.4 percentile not the other two values. Is that correct?

chriswmackey commented 7 years ago

@mostaphaRoudsari , It would be nice to have both the 99.6 and 0.4 percentile as well at the 99 and 1 percentile. Different engineers and different building programs use different design temperatures depending on how important it is to maintain set points.
If I had to pick one pair, it would be the 99.6 and 0.4 percentile but, again it would be really helpful to have both. -Chris

mostaphaRoudsari commented 7 years ago

@chriswmackey and @alemenchaca. I found this by accident. Should be a good temporary solution.

chriswmackey commented 7 years ago

@mostaphaRoudsari , Interesting. This seems like a less-visually-appealing version of EPWmap but it has most of the quick facts that we typically need from weather files. Particularly, I'm finding that the elevation data is also helpful. It's definitely helps explain why some parts of Ethiopia and Kenya are so comfortable.