30 YEARS PERFORMANCE GUARANTEE
Sonnenstromfabrik also offers its customers the option of extending the product guarantee for glass/foil modules to 25 years and for glass/glass modules to 30 years.
| Industry standard | Excellent Glass/Glass | Excellent | |
| Product guarantee | max. 10 years | 20 years | 12 years |
| Optional extension of product guarantee |
no | yes, optional 30 years | yes, optional 25 years |
| Performance guarantee | in steps | linear | linear |
| Performance guarantee after 1 year | no | 97% | 97% |
| Performance guarantee max. | 20 years | 30 years, 87% | 26 years, 80% |
| Annual max degradation after year 2 |
n/a | 0.35% | 0.68% |