PHYWE

Solar ray Collector

Principle

The solar ray collector is illuminated with a halogen lamp of known light intensity. The heat energy absorbed by the collector can be calculated from the volume flow and the difference in the water temperatures at the inlet and outlet of the absorber, if the inlet temperature stays almost constant by releasing energy to a reservoir. The efficiency of the collector is determined from this. The measurement is made with various collector arrangements and at various absorber temperatures.

Training Objectives:

  • Absorption
  • Heat radiation
  • Greenhouse effect
  • Convection
  • Conduction of heat
  • Collector equations
  • Efficiency
  • Energy ceiling

Technical Specifications:

  • Solar collector
  • Laboratory thermometers, -10...+100°C
  • Power supply 0-12 V DC/ 6 V, 12 V AC
  • Heat exchanger
  • Stand for solar collector
  • Immersion heater, 1000 W, 220-250 V
  • Halogen lamp 1000 W
  • Hot/cold air blower, 1700 W

Characteristic curves of a solar cell

Principle

The current-voltage characteristics of a solar cell are measured at different light intensities, the distance between the light source and the solar cell being varied.
The dependence of no-load voltage and short-circuit current on temperature is determined.

Training Objectives:

  • Semiconductor
  • p-n junction
  • Energy-band diagram
  • Fermi characteristic energy level
  • Diffusion potential
  • Internal resistance
  • Efficiency
  • Photo-conductive effect
  • Acceptors
  • Donors
  • Valence band
  • Conduction band

Technical Specifications:

  • Solar battery, 4 cells, 2.5 x 5 cm
  • Rheostats, 330 , 1.0 A
  • Ceramic lamp socket E27 with reflector, switch, safety plug
  • Filament lamp with reflector, 230 V/120 W
  • Hot/cold air blower, 1700 W
  • Meter Scale, l = 1000 x 27 mm
  • Digital multimeter
  • Laboratory thermometers, -10...+100°C

Characteristic and efficiency
of PEM fuel cell and PEM electrolyser

Principle

In a PEM electrolyser, the electrolyte consists of a proton-conducting membrane and water (PEM = Proton Exchange-Membrane). When an electric voltage is applied, hydrogen and oxygen are formed. The PEM fuel cell generates electrical energy from hydrogen and oxygen. The electrical properties of the electrolyser and the fuel cell are investigated by recording a current-voltage characteristic line. To determine the efficiency, the gases are stored in small gas meters in order to be able to measure the quantities of the gases generated or consumed.

Training Objectives:

  • Electrolysis
  • Electrode polarization
  • Decomposition voltage
  • Galvanic elements
  • Faraday´s law

Technical Specifications:

  • PEM fuel cell
  • PEM electrolyser
  • Resistor 10 2%, 2W
  • Resistor 5 2%, 2W
  • Resistor 2 2%, 2W
  • Resistor 1 2%, 2W
  • Graduated cylinder, 100 ml
  • Rubber tubing, d = 4 mm
  • Wash bottle, plastic, 500 ml
  • Beaker, 250 ml, low form, plastic
  • Stopwatch, digital, 1/100 s
  • Cobra4 Mobile Link