use for some typical reasons why solar access can be important:
Solar Access for Passive Solar Heating - The conditional statement should request sun vectors for any hours below the balance point of the building (the temperature at which the building starts requiring additional heating). For residences, this can be as high as 18C and for commercial/retail buildings with high internal heat gains, this can be as low as 10C. 16C is around what you might find for some residences with better insulation and is probably the reason why that is chosen in the file.
Solar Access for Outdoor Thermal Comfort - The conditional statement should request sun vectors for any hours below the lower limit of outdoor comfort (UTCI uses 9C for this lower limit).
Solar Access for Health of Plants/Trees in a Park/Garden - This is a bit of the opposite of the other metrics since you want hours of the warmer season. In this case, I usually use solar radiation as the annualHourlyData with the conditional statement and I request hours that are above a certain radiation level (where the plants are benefiting the most). I then use an analysisPeriod to get rid of any months of the year when the trees don't have leaves on them.
Hope this helps,
-Chris…