Benny said:
Figures I have for Perth say N facing, vertical, window/wall receives 4.14kWh/sqm/day in winter. Aust solar radiation data handbook.1995
That's really interesting. BOM says that Perth winter insolation for a horizontal surface is 9.7MJ/m2/day.
Presumably due to Lambert's cosine law (and total internal reflection) this means that 1m2 of vertical north facing window is only able to admit less than 50% of the available solar insolation.
Another misquote from the passive solar literature is that a north facing window admits 1000W/m2 i.e. one bar radiator. Checking the weather data suggests it more likely to be half of this during winter.
Posted Monday 4 Jul 2011 @ 11:07:23 am from IP
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