Curves

For a more profound and detailed optimization the curves for ZEH, the heating hours (HH, hours where the FRT is below the comfort limit) and the cooling hours (CH, hours where the FRT is above the comfort limit) are shown as a function of gamma for situations without sun-shading (SS = 0), with internal sun shading (SS = 2) and external sun-shading (SS = 5), the SS to show the reduction factor attainable. The curves are shwn for the South-, North- and east (=West) sides and also for two different levels of internal sources: = W/m2 and 40 W/m2 from 0800 am to 0500 pm. Intermediate values can be estimated by interpolation. The values of table 1 represent an extract from these curves. The curves themselves allow a more detailed discussion of deviations and there effects. Instead of aiming at a maximum of ZEH one could also aim at a regime with no cooling need (in a cold climate) or no heating need (in a warm climate), leading to lower values for ZEH but allowing to eliminate one fill system.