Design Of PV-Electrolysis System For Hydrogen Generation

PV Hydrogen is the Hydrogen produced using solar energy as the energy source. The use of solar energy to produce hydrogen can be conducted by two processes namely:

• Water electrolysis using solar generated electricity
• Direct solar water splitting.

A typical PV-electrolysis system consists of the following :

• Triple-junction solar cell
• The three subcells of the PV are made of InGaP (Eg=1.895 eV), GaAs (Eg=1.414 eV) and GaInNAs(Sb) (Eg=0.965 eV) respectively
• The two PEM electrolysers consist of Nafion membranes coated with 0.5 mg cm−2 Pt black catalyst at the cathode and 2 mg cm−2 Ir black catalyst at the anode.
• The two electrolysers are connected in series with the PV cell and a potentiometer to measure the current through the circuit.
• Water is pumped into the anode compartment of the first electrolyser, whereas the cathode of the first electrolyser had no input flow.
• The water and O2 effluent from the first electrolyser’s anode compartment shall flow into the anode compartment of the second electrolyser.
• Hydrogen from the cathode side of the first electrolyser shall flow into the cathode side of the second electrolyser.
• The H2 and O2 products flowing out of the second electrolyser are collected and whereas the residual water is fed back into a water reservoir and recycled through the system.
• The temperature of the electrolysers is to be held at 80 °C, as perthe standard operating conditions for industrial water electrolysers