1. On Infrastructural Support and Human Resource Developments for Solar PV Industry Tai-Ran Hsu, ASME Fellow Professor Department of Mechanical and Aerospace engineering San Jose State University San Jose, California, USA www.engr.sjsu.edu/trhsu/ E-mail: tai-ran.hsu@sjsu.edu Prepared for discussions at Solar America Forum Clean Tech Institute, San Jose, California September 24, 2009

2. ● A silicon solar photovoltaic (PV) cell is a microelectromechanical (MEM) device made of semiconductor material ● Several microfabrication processes used for integrated circuits (ICs) have been adopted for producing silicon solar PV cells. ● 50 years of unprecedented rapid growth of IC technology has boosted its production to 2 trillion units in transistors, with its applications expanding from: Mainframe computers to: Consumer electronics to: Personal computers to: Information technology with Internet to: Wireless phones and portable devices, and to: Renewable sustainable ENERGY for years to come ● Solar PV industry thus has a lot to learn from the success of the IC industry - In particular, the infrastructure support and HR development from that industry The IC and Solar PV Industry

3. A glance at solar PV technology ● Electric power generation by solar PV in the world has shown significant increase in recent years: ● A clear trend: Generating capacity of single solar PV power plants has increased dramatically too: ● The largest US power plant in Nellis Air Force Base in Nevada built in 2007 generates 14 MW with 72,000 solar panels ● The PG&E’s Majave Park project will generate 553 MW in 2011 ● The First Solar’s plant in Inner Mongolia in China will generate 2 GW power in 2019 ● Price for solar PV generated electricity is low, but capital and construction costs are extremely high (e.g., $100 million to produce 14 MW power at the Nellis Station) 6 GW in 2008

4. ● The enormous capital and construction costs of solar PV power generation has made it extremely hard for the solar PV industry to survive without substantial government’s subsidy and its generous incentives to the consumers ● Adequate infrastructural development to the constructing solar PV plants is a viable solution to mitigate the capital and construction costs – A good lesson to learn from the IC industry ● The infrastructure supports to the solar PV industry can be classified into 3 categories: ● “Soft engineering” support for manufacturing and installations, and ● Equipment and facilities for reliability testing for quality assurance and in-field operations and maintenance, and ● Smart power inversion and storage grids Infrastructural Supports for Solar PV Industry ● There appears lack of standards in quality assurance and reliability of solar PV cells and modules manufactured by the solar PV industry. These shortcomings will likely lead to significant costs in field operations and maintenance of solar PV power generating plants years after installations.

5. ● “Soft engineering” infrastructural supports include the development of: ● Standards for design, materials, fabrication processes, inter-connect and packaging, pre-shipping testing, and installations ● Codes for design, fabrication, assembly, packaging and testing, and installation ● Certificates for installation and testing Infrastructural Supports for Solar PV Industry ● Infrastructural support in equipment and facilities for reliability testing for: ● Thermomechanical reliability testing ● Burn-in and accelerated aging testing ● Self-testing and testing during use ● Smart power inversion and storage grids: ● Cost effective “Balance of System” (BOS) with standard common power conditioning equipment ● Smart energy storage and ‘Net metering” equipment connecting to utility power generators

6. Thermomechanical Reliability Testing for PV Cells and Modules There is a need for routine tests performed before the solar cells or modules are shipped to the customers: Thermal Shock Tests - ? o C +? o C Δt ? according to specification Time, t Temperature, T(t) Thermal Cycling Tests - ? o C + ? o C Time, t Temperature, T(t) Δt 1 ? Δt 2 ? Δt3?Δt3? Burn-in Tests Solar cells or modules are placed in autoclaves at specified temperatures and humidity for hundreds of hours for endurance.

7. Burn-in and Accelerated Aging Testing for Solar PV Cells and Modules ● Burn-in tests are conducted after all components are assembled into a module under conceivable environment conditions, e.g., temperatures, humidity and vibrations ● These tests are necessary because many solar modules can fail to perform due to invasion of unwanted foreign substances, e.g., dust and moisture to some packaged components ● A typical failure rate history for a product – a “Bath-tub” curve may be introduced: Failure Rate Time (in logarithmic scale) Useful Life Infant Mortality Wear-out ● The GOAL of “Burn-in” tests is to have the “Infant mortality” failure of the modules occurs in the factory, but not in the field. ● The Arrhenius model could be used to design the timing and conditions for the “accelerated aging tests” of solar modules

8. Self Testing and Tests During Use Self Testing ● Self testing devices need to be developed and attached to the solar modules to determine if the modules are performing the expected functions ● These tests can be carried out by applying simple electric stimuli to the module Testing During Use ● It is used for calibrations of solar modules in the designed life span ● Input for these tests usually involve the natural loads, e.g., temperature and humidity as in self testing. ● Testing during use ensures the proper functioning of the solar modules for the intended applications

9. Human Resource Development for Solar PV Industry Technology Engineering R&D Infrastructural Support Dev. Develop Standards, Codes and Certificates R&D on: quantum physics; Material science; Optoelectronics; Electrochemistry;Micro- and nanotechnologies Design, Fabrication, Assembly- Packaging-Testing Data logger and processing; Program- ming, Installation, Construction, Testing, Operations &Maintenance Universities & government laboratories Industry; Governments Professional societies Community colleges Funding & Supporting Agencies: NSF; DARPA; DOE, DOC, DOL, NIST, Industrial consortia similar to SRC, SEMATECH Business & Marketing Business development; Technology management; Global marketing A layered cake model

10. Summary on Infrastructural Support & Human Resource Development to Solar PV Industry ● Standardization is the foremost critical element for sustaining a mature solar PV industry ● The lack of standardization of solar PV industry does not only result in high production costs, but it will become serious issues relating to parts repair and replacements of solar modules years after field operations – it will be a serious maintenance problem ● Lack of codes for design and manufacturing of solar modules in the industry also contributes to the production cost, as well as quality assurance of the products ● Universally accepted certifications and reliability testing of solar PV cells and modules, and power plant components in design and construction are essential to the quality and public safety, and it will mitigate costs in operations and maintenance of large solar power generating plants ● US is facing with stiff competition in global solar power market with Germany and Japan ● The competition will be stiffer with China now is ready to be in this international area ● Superior human resource development is the only way the US solar PV industry can expect to sustain its competitiveness in global marketplace

11. ● There appear sporadic efforts on developing standards, code and certificates by: ● Governments, e.g., The Department of Energy, California Department of Forestry and Fire Protection ● Government agencies, e.g., National Renewable Energy Laboratories and Sandia National Laboratories ● Private research organization, e.g., North American Board of Certified Energy Practitioners (NABCEP) ● The solar PV industry, e.g., Trina Solar ● More concerted efforts are needed to develop universally accepted industrial standards, codes and certificate programs Recommendations on Infrastructural Support & Human Resource Development to Solar PV Industry

12. ● Many attribute the success of the IC industry to the two industrial consortia: ● Semiconductor Research Corporation (SRC) for the R&D of semiconductor technology, and ● The International SEMATECH (formerly SEMATECH) for solving common manufacturing problems and regaining competitiveness for US semiconductor industry ● Good track records of supporting R&D at American universities by SRC and SEMATECH ● It will make sense for the solar PV industry to adopt this model by establishing similar agencies for developing the necessary infrastructural supports and human resource development ● Governments’ support and university’s contributions in R&D are essential to the industry’s efforts in developing vital infrastructural supports and human resources - as in the case of the semiconductor and IC industries in the past 50 years