Spring and fall: Set the tilt equal to your latitude. The solar panel's best angle determines how much sunlight your panels capture throughout the year, directly impacting energy production and ROI. A correctly tilted system can improve efficiency by 5–10% annuall y, reducing payback time and boosting long-term savings. In today's blog post, we'll explain tilt angles for. This article explains how tilt and roof pitch interact with location, orientation, shading and mounting options to determine the most effective angle for residential and commercial solar arrays. Tilt Determines Direct Sun Exposure, Incidence Angle, And Seasonal Performance.