TÜV Rheinland Blog

Bankability and Reliability on Solar Part 1

Posted by Hope Mascott on Fri, Aug 31, 2012 @ 10:15 AM

This is part one of two and will focus more on banking in solar. Power plants are spreading and starting to contribute a legitamate amount of energy to a world in dire search of it. Because of the growing industry and the money to be made, investors need to consider module reliability in their risk management analysis. The best method to ensure product reliability and safety compliance is to test products to universally accepted standards and certify that compliance for the life of the product.

Important decisions in the planning phase of power plants include output assessments, extensive site evaluations, as well as testing the suitability of components, assessing in-situ module performance and evaluating the plant design. Test services are all part of a product development, which we believe helps is essential to the value-chain. The financial performance of the plant will hinge on regular monitoring and inspections.

Laboratories with a strong solar background can provide specific test requirements for modules or systems envisioned to operate in certain climates. These tests are designed to complement the independent assessment of module performance to the industry standards. They are much tougher and include unnanounced inspections. There are two credible programs that have gained support in the marketplace. 

The National Renewable Energy Laboratory’s (NREL)

Two stress tests, thermal cycling (TC) and damp heat exposure (DH), are selected for the TTF protocol and are extended beyond the IEC Design and Qualification standards. In this method, the sample is subjected to multiple sequential exposures and measured for performance along that protocol. This reliability testing also involves determining when and how the unit under the test failed. 

 The U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy’s (EERE) 

This Test is designed to gather and report degradation through the course of the test sequences. Similar to the NREL test, certain simulated environmental stresses are repeated sequentially. The maximum power output degradation is tracked and should remain within a prescribed window of the initial power rating data. An induced potential is also subject to the modules under the test in the DH sequence. Power drop, leakage current and visual observations are important factors in the final result.

 See us at the SPI Show in Orlando, Sept 11-13th, booth 3325.

Topics: Solar/PV