To calculate the distance between the front and rear of solar photovoltaic panels, you'll need to consider several factors, including the dimensions of the panels, the tilt angle of the panels, and any mounting structures or racking systems. 707H} {tan left ( arcsin left ( 0. 399 sin Phi right) right)} ] where: The row spacing of a photovoltaic array is the distance between the front and rear rows of solar panels. Winter Solstice Sun Angle – Since the sun is at its lowest elevation, panels cast their longest shadows. Tilt Angle – The more your panels tilt, the higher the. Estimate the ideal spacing between rows of solar panels to minimize shading and maximize efficiency based on latitude, tilt, and panel height. Formula: Spacing = Height / tan (Solar Altitude).