Question

The sun at 2pm in March has an altitude angle of 40^o, an azimuth angle of 30^o, and generates direct solar radiation of 500W/m² in a plane normal to the beam.

What is the direct solar radiation striking a West-facing roof with a slope of 15^o (convention for azimuth is the one used in the lecture, i.e solar azimuth for South is 0°)?

The sun at 2pm in March has an altitude angle of 40°, an azimuth angle of 30°, and generates direct solar radiation of 500W/m2 in a plane normal to the beam. What is the direct solar radiation striking a West-facing roof with a slope of 15º (convention for azimuth is the one used in the lecture, i.e solar azimuth for South is 0°)?

Answer 1

y = south R = Radiation = 500 W/m² 140) 30 2 سمی 2 150 North E Ra sin 30 Components of R! Ry Rz R cos 40 R los 40° cos3o" R sin 40° OR 191.5 t 331.7 ſ + 321.4k For waste vector surface facing direction roof for of slope 15, perpendicular to the the is : A 6 N cos 15 sin 15° h + 0:26 î t 0.96 to We need Ñ. That find Ŕ along is component of projection of vector R on Ř. (dot product (191.5 x 0.26 +(32104 X 0.36 e Required value 358. 33 W/m2