Each Solarday photovoltaic panel features a modern design that enhances the materials used to make them, all combined with high efficiency and long life. The polycrystalline, or multicrystalline, module has slightly lower efficiencies than mono and needs more area to produce 1 Kwp of power: in fact, about 7 square meters are required. The cells are iridescent blue in color. Over the years, the difference between the output of poly and mono has gradually narrowed. The lower price makes them the most popular solution, so much so that about 80 percent of the panels installed in Italy are poly. In fact, the polycrystalline module represents a good compromise between cost, area occupied, production yield and efficiency.