Both electrodeposition and performance assessment of new photocathode design are carried out using cuprous oxide for solar hydrogen production. The maximum delivered light can be collected using the mesh dome design of the photocathode, and the light can also reach the farthest photocathode surfaces via the mesh shape. The stainless‐steel mesh dome electrode is coated with cuprous oxide using the electrodeposition method. This photocathode is examined in an alkaline electrolyte solution of potassium dioxide for hydrogen production. Two light angles are studied to explore the effects of the new photocathode design on the hydrogen yield rate and associated energy and exergy system efficiencies during the daytime, where the light angles change. The maximum hydrogen production rates are generated experimentally at 0.1 m KOH at the 45° tilt light, and vertical light positions are 5.13 and 5.58 μg s −1 , respectively. Moreover, the highest exergy and energy system efficiencies are 0.82% and 1.18%, respectively, under vertical light, while they are 0.75% and 1.09% under tilted light conditions. The improvement of hydrogen production rates at tilted light can reach around 75.6% of the enhancement by vertical light due to the new photocathode design.