Sri Saravanas Agencies A truly affordable solar panel system is one that offers the best value for your investment. The most affordable option is often a balance between initial cost, long-term performance, and the significant government subsidies available. The most common and cost-effective solar panels today are monocrystalline panels and, to a lesser extent, polycrystalline panels. While monocrystalline panels have a slightly higher price per watt, their superior efficiency and durability often make them a better long-term investment.