others showing the profile (elevation) view and the relative heights of these obstacles.
b). Assume that your goal is to maximize radiation absorption in all seasons. Where would be the best place to put a solar collector and to what angle should the collector be adjusted for the solstices and equinox? Using the diagrams that you have drawn for (a), indicate how you would adjust your solar collector for obstruction due to the presence of those obstacles.
Question 2: The slope, aspect and albedo are three important variables upon which the radiation budget depends. Given the values for surfaces (at 34oN) in the Table below, calculate the rates of solar heating (SH) at solar noon on the equinox for the four surfaces using the following equations. Present your answers in a Table format and attach your calculations. Pay attention to your units.
SH = Si(1-α) cosΘ
where SH is solar heating in Wm-2, Si is the radiant flux density incident upon a horizontal surface
(1200 Wm-2), α is albedo and Θ is the ground sun angle in degrees.
The ground-sun angle is calculated using the following equation:
cos Θ = cos β cos Ζ + sin β sin Ζ cos (Ωsn - Ωsl)
where β is the angle at which the surface is inclined (slope), Z is the zenith angle (34o), (Ωsn is the solar azimuth angle (south) and Ωsl is the aspect (given in the Table below).
Write a paragraph on what your calculations show about the effects of changing slope angle, aspect, and albedo.
SURFACE ROOF WALL FIELD ROCK-SLOPE
SLOPE 20 90 8 30
ASPECT south north south east ALBEDO 0.20 0.40 0.25 0.20
Solar radiation enters a narrow, rectangular, east-west canyon at noon. The valley is 100m wide and the sides of the canyon are 100m tall. The walls and floor of the canyon have an albedo of 0.30. Consider how an individual solar beam is depleted by reflection within the canyon. This beam enters the canyon at 45 and strikes the south slope at 70m from the valley floor and is reflected at 90o. Using your computer or graph paper and a straight edge (i.e. Do not draw freehand), draw a diagram showing these exchanges and calculate the effective canyon albedo.
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