SunPowers X-22 360 watt panels produce the most energy and take up much less space. They boast the highest efficiency available on the market by any manufacturer and deliver 44% more power per panel, which means you can generate more power in smaller spaces, with fewer panels. Simply put, these panels convert more sunlight to electricity, producing 75% more energy per square foot over the first 25 years. The X-22 is designed for durability, using the SunPower Maxeon Solar Cell—the only cell built on a solid copper foundation. These cells make the panels virtually impervious to the corrosion and cracking that degrade conventional panels. The X-22 ranks #1 in Fraunhofer durability test and 100% power maintained in Atlas 25+ comprehensive durability test.