In this experiment we have been asked to discover whether a photovoltaic cell or a solar panel is more efficient in the way it uses the energy it receives from the sun.
A photovoltaic cell mostly consists of the element silicon. The cell works through the application of the photoelectric effect. This works when photons in the sunlight hit the solar panel and are absorbed by the silicon. The electrons on the atoms of silicon are knocked off and flow through the material, which in turn produces electricity
1. Record the values shown on the voltmeters and ammeters
2. Turn off the power pack and allow bulb to cool (about 2 minutes)
3. Turn power pack back on and record voltage and current readings
4. Continue steps 3 and 4 until you have 6 sets of results
Calculating the efficiency of the cell
To calculate the efficiency of the photovoltaic cell, the power of the circuit connected to the bulb must be calculated using average values for V (voltage) and I (current) and the equation P (power) = I (current) x V (voltage). Then calculate the power of the circuit connected to the cell, using average values for V and I again. You now have the input power (from the bulb) and the output power (from the cell).
So in order to calculate the efficiency of the cell, calculate:
X 100 = Efficiency of the cell
A solar panel (or Solar Water Heating system) works by collecting energy from the light, which then heats the water being pumped through coiled pipes inside the solar cell. The hot water is then pumped through to another coil, which heats the water in a storage tank.
1. Wait 10 minutes and record the temperature change in the water
2. Record V (voltage) and I (current) values for the power system connected to the bulb
3. Turn off the power and allow water to cool (about 10 minutes)
4. Repeat steps 2 to 4 until you have 6 sets of readings...