01-08-2012, 04:49 PM
SOLAR PANEL OUTPUT POWER
SOLAR PANEL OUTPUT POWER.docx (Size: 240.44 KB / Downloads: 38)
INTRODUCTION:
Power output of the UTJ solar panel cell can be derived by verifying the I-V characteristics of the given cell (via...Graph).The required current and voltage is availed through the optimized specified value (shown in the specification table).
After getting down with the optimum power that the UTJ cell can generate, then we look up to the various orientations (i.e., the angles generated between the sun and the solar cell) of the UTJ cell. Calculating the power output in case of various angles we notify, at what case how much output power is generated.
Factors affecting solar panel output power:-
If the incident light is perpendicular to the surface of the solar cell, the cell’s output will be at its maximum. As the incidence angle deviates from the normal, the output
current will decrease. The new value of the short-circuit current, with a light incidence angle θ from the normal (i.e., the angle between the incident light ray and the normal to
the cell surface), is Isc cosθ. The open-circuit voltage is not strongly dependent on the amount of light received, but does decrease slightly for large angles from the normal.
The prediction of current follows well with experimental data for minor θ. As the angle from the normal approaches 60° and above, the current becomes less than the predicted
value of 0.5Isc. This is due to optical refraction and reflection at the surface of the cell, whose effects become important at large angles.
Studying the effect of temperature is important for solar cells operating in space. The temperature in space swings very widely. The short-circuit current is not strongly
dependent on temperature, but it does increase slightly with increasing temperature. The open-circuit voltage, however, is more temperature-dependent.
Analogous Condition:-
Satellites orbiting the Earth pass through a shadow region on the opposite side of the Earth from the Sun. Depending on the type of orbit, this can happen just a few times a year or every few hours. During these so-called
‘eclipses’, the solar panels cannot produce electrical energy and the satellite would not only be unable to operate, but would also freeze to incredibly low
temperatures (eventually around –270°C) if a backup power source were not available. Electrical energy therefore has to be stored onboard the spacecraft
when in sunlight for consumption during these eclipses.