420W solar panels tend to weigh about 52 lbs, being approximately 82 inches long and 42 inches wide. Solar modules with this output rating are predominantly monocrystalline and usually have 72 cells or more. Their size will not excessively restrict your. Higher Energy Conversion Rate - Covered by monocrystalline silicon solar cells, the solar panel adopts multi-layered cell technology to generate energy from the sunlight and perform better with higher conversion efficiency that up to 23. 4% than other conventional panels. These are much better and more efficient than monocells. Leveraging REC's advanced heterojunction (HJT) cell technology and a sleek, compact.