# Assignment: Solar Energy

A proposed low energy building incorporates 150 m^2 of flat plat collectors and 100 m^2 of photovoltaic (PV) panels. Both systems are located on the vertical south facade of the building.

A) For the flat plate solar collector calculate the following:
• the power absorbed by the collector;
• the collector losses;
• the useful output;
• t outlet water temperature (°C).

Use the equations supplied within the accompanying course module and assume the following data.

G, the average solar radiation on a south facing vertical surface =100 W
tc, the transmission factor of the cover plate = 0.9
ap, the absorption of the back plate = 0.7
UA, the collector heat loss coefficient = 50 W/°C
Tc, the average temperature of the collector plate = 50°C
Ta, the average air temperature = 8°C
C, the water specific heat = 4,180 J/kg°C
m, the water flow rate = 0.02 kg/s
Twi, the water inlet temperature = 10°C

B) For the PV panels calculate the following:

• the electrical output Pmax.

Use the equations supplied within the accompanying course module and assume the following data.

PSTC, the power output of a cell at standard test conditions = 5 W
n, the number of cells in a panel = 100
m, the total number of panels = 50
G, the average solar radiation on a south facing vertical surface = 100 W
Pp, the temperature coefficient of the cells = 0.005
T, the average cell operating temperature = 30°C

C) Given that: Energy (kWhrs) = [ power (W)/1000] ´ time (hours) , calculate the total electrical energy from the PV panels and the total heat output from the solar collectors over a year.

D) In 800 words describe some of the advantages of generating heat and power from the sun and outline some possible uses for the heat and power produced by a building-integrated PV array and solar collector.