The Effect of Shading Calculation on Passive Solar Gains
Abstract
Parametric studies and sensitivity analyses applied on calculation of energy need for space heating indicate that passive solar gains in well insulated buildings appear to be a very important but on the other hand quite unreliable source. Generally used calculation procedure (ISO 13790) assigns every translucent construction in monthly based calculation each month for the whole year the same value of shading reduction factor and total solar energy transmittance. The question is how appropriate is this simplification in case of low-energy, passive or net zero energy houses. The paper deals with the comparison of the ISO and more precise calculation of passive solar gains in situations with extended shading caused by usual building construction elements. Focus is stressed on shading reduction factor, total solar energy transmittance and utilization factor that differ for various shading situations every month in the course of the year. Finally the effect of shading calculation on energy need for space heating in a building is presented.