Work out cabinet heat load instantly with clear inputs, formula shown and shareable results.
Cabinet heat load is the sum of every component's dissipation plus external gain. The airflow needed for a given temperature rise is about 3.1 times the watts divided by the permitted rise in degrees, which comes from the specific heat and density of air.
Cabinet heat
airflow (m3/h) = 3.1 x watts / permitted temperature rise; 1 W = 3.412 BTU/h
From air's volumetric heat capacity, about 1.2 kJ per m3 per K, converted to cubic metres per hour per watt per degree.
Yes, and it can dominate. An enclosure in direct sun can absorb several hundred watts, which is why sun shields and light colours matter outdoors.