Based upon the experiences of otherindustries, technology developments in cell efficiency and increases inmanufacturing economies of scale will not be enough to reach grid parity goals as fast as the world desires.
The solar PV industry needs to look at meaningful cost reduction through a global, robust andwell-organized supply chain. The current learning curve for the industry is not as steep as other electronic industries, especiallysemiconductors which use many of the same processes, materials, andsuppliers as PV. A faster learning curve for the solar PV industrycould be accomplished through better industry collaboration, includingindustry standards and technology roadmaps.
A Moore’s Lawfor PV?
The progress made by semiconductors incost reduction is one of the technological marvels of our time. Since1975, the cost of one transistor has been reduced by a factor of about4,000,000. This achievement has often been ascribed to Moore’s Law,the prediction that the number of transistors that can be placedinexpensively on an integrated circuit would double approximately everytwo years. Learning curve cost reductions summarized by Moore’s Law has led to the dramatic market expansion of chips into nearly every facetof modern life, and many observers see it as a useful guide to costreduction in the PV industry. While thin film and c-Si cells do notbenefit from lithography-enabled feature-size reductions that comprisemuch of cost reductions in semiconductors, much of Moore’s Law isdirectly related to productivity, yield, and other cost reductions notrelated to feature-size reductions. Since PV manufacturing is basedupon many of the same processes and materials as IC and displaymanufacturing, there remain important learnings from these industriesthat can be applied to solar cells and modules.
For over twenty years, keeping pace withMoore’s Law was accomplished by individual companies, workingindependently on common technical problems. For decades, the idea that a technology roadmap was semiconductors was necessary to sustain anacceptable rate of industry progress was simply not part of anyone’sexpectation. It was not until the 1980’s—twenty years after Gordon’sMoore’s observation about the rate of improvement in semiconductors—that the first international roadmap for technology development wasproduced. Today, the industry-wide agreement to advance the industry as a common rate– characterized by the International Technology Roadmapfor Semiconductors (ITRS)–is recognized as a natural and necessarycompass and integral component of the IC industry.
The ITRS document describes thetechnological targets required to achieve Moore’s Law over numerousareas from research design, to photolithography, materials, and otherparameters. It is updated annually and provides a technology forecastover a rolling 15-year timeline. It has thousands of contributors andpages and is used by hundreds by companies in all regions of the world. Many see the ITRS process as an effective way to identify and targetkey requirements and contend that “innovation is spurred by identifyingrequirements.” The open and public process fosters a healthy “beat theroadmap” behavior by the industry. Some see the PV industry as verymuch a “parallel universe” to semiconductors who can benefit from theexperience of the ITRS.
There are both similarities anddifferences between the critical roadmap issues in chips and PV. Bothinvolve substrates, interconnects, absorber/efficiency, metrology,packaging, and test. Both have common business drivers such as costreduction, throughput, quality and reliability, and sustainability.Roadmaps can effectively identify technology gaps and serve as “learning tools for the industry.” With more exposure of the critical technology gaps, more focused and cost effective innovation can occur. PV isclearly different from chips, however, and does not have the powerfulorganizing paradigm of the next process node that helps ground thesemiconductor roadmap.
Industry standards also have a closerelationship to technology roadmaps, and many view them as a naturalconsequence of industry collaboration and roadmapping. It has been said that “roadmaps without standards don’t work.” Roadmaps are the groupview of the technology path over time. Standards are the tools theindustry uses to identify the set of specifications that define industry requirements. In other words, standards define where the industrycollaborates, and roadmaps establish where the industry competes.Several studies have identified billions of dollars in industry coststhat the semiconductor industry has eliminated with standards. Arethere similar costs in the PV industry that can be reduced with a smartstandards effort and gets us closer to grid parity? Many believe thereare.
The PV industry is just starting toaddress roadmaps and standards. Several manufacturing standards havealready been adopted by the industry and there is a growingparticipation by key constituents in the standards development process. Active PV standards committees are in place in North America, Europe,Japan, and Taiwan under the SEMIInternational Standards Program, the same platform and process thatsupports IC manufacturing standards. One major standard specified howdifferent machines or processes communicate together, a fundamentalrequirement for the modern automated factory and huge contributor tomanufacturing efficiency. The standards effort in PV appears to be well on its way to contributing to a steeper learning curve
EuropeanProgress on Collaborative Technology Roadmap
Roadmaps are just now being considered by the industry. A recent survey of cell and module manufacturers,equipment and material suppliers, and other key players ranked lack ofindustry roadmap and effective collaboration second behind governmentpolices as a key barrier to industry growth. However, some industryparticipants believe it is too early for a technology roadmap and thatengaging in an open, public dialogue could be harmful. Collaborationopponents object that roadmaps cannot define industry growth in such adynamic market environment.
Last month, SEMI PV Group announced theformation of the EuropeanCrystalline Cell Technology and Manufacturing Group (CTM). Thisspecial interest group of eight crystalline solar cell manufacturers(Q-Cells, Deutsche Cell, Bosch Solar Energy, Schott Solar, Sovello,Sunways, SolarWatt/Systaic Cells and Solland) is working together in apre-competitive environment to address the technology challenges facingthe photovoltaic industry. The CTM Group has begun work on acrystalline solar cell technology roadmap up to the year 2020. Thisparticular roadmap describes the development of crystalline solar celltechnology with focus on materials, manufacturing processes, and product development. As part of this activity, the priority of the CTM Groupwill be the definition of the development processes for raw materials,cell technology and cell manufacturing. The group also aims to optimizethe interfaces within the entire manufacturing supply chain to helpachieve this goal. How this European group leverages their roadmapactivities to the global supply chain and connects with industry cluster efforts in other regions have yet to be determined.
Technology roadmaps and industrystandards are complex issues for the industry to consider, involvingfundamental issues of competition and cooperation. Along with the CTMGroup, discussions are underway between other key stakeholders aroundthe world trying to identify areas where cooperation makes sense. Asthese discussions continue, the industry has the opportunity to learnfrom the semiconductor industry and find its own path, to find its ownMoore’s Law that drives down costs and accelerates grid parity, enabling a great solar era unsupported by government incentives.
For continuing dialog on industrycollaboration, check out PV Group organized programs at Intersolar NorthAmerica.
PV Group, The Grid – April 2010
By Bettina Weiss, Sr. Director, SEMI PVGroup