Step-Stress Accelerated Degradation Testing for Reliability of Solar Reflector

• Activity Number: 253
• Type: Contributed
• Date/Time: Monday, August 1, 2011 : 2:00 PM to 3:50 PM
• Sponsor: Section on Physical and Engineering Sciences
• Author(s): Jinsuk Lee*+ and Ryan Elmore and Cheryl Kennedy and Wesley Jones
• Companies: National Renewable Energy Laboratory and National Renewable Energy Laboratory and National Renewable Energy Laboratory and National Renewable Energy Laboratory
• Keywords: Accelerated Testing ; CSP ; step-stress

Abstract

Concentrating solar power (CSP) technologies use large mirrors to concentrate sunlight and convert the thermal energy collected to electricity. Commercialization of CSP technologies requires advanced optical materials that are low in cost and maintain high optical performance for lifetimes of 30 years under severe outdoor environments. In order to meet these stringent requirements, step-stress accelerated degradation testing (SSADT) technique was introduced to the CSP program at the National Renewable Energy Lab (NREL). In this talk, we will discuss the underlying statistical and physical theory used to construct the SSADT methodology for the CSP program and how it can be used to predict service lifetime, including warranty time and mean-time-to-failure, failure/degradation rates at use-conditions, activation energy, acceleration factors, and upper limit level of stress. We will also discuss the accelerated environmental conditions that are encountered in typical accelerated CSP testing programs.