Seminar Archive Summaries

Long-term Trends in the Energy Efficiency of Computing: Why We Can Expect Ever More Amazing Mobile Computing Devices in the Years Ahead

Jonathan Koomey, Stanford University, Civil and Environmental Engineering

Monday, October 31, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

This talk will explore the relationship between the performance of computers and the electricity needed to deliver that performance. Computations per kWh grew about as fast as performance for desktop computers starting in 1975, doubling every 1.5 years, a pace of change in computational efficiency comparable to that from 1946 to the present. Computations per kWh grew even more rapidly during the vacuum tube computing era and during the transition from tubes to transistors but more slowly during the era of discrete transistors. As expected, the transition from tubes to transistors shows a large jump in computations per kWh.

The main trend driving towards increased performance and reduced costs in the microprocessor era, namely smaller transistor size, also tends to reduce power use, which explains why the industry has been able to improve computational performance and electrical efficiency at similar rates. If these trends continue (and we have every reason to believe they will for at least the next five to ten years), this research points towards continuing rapid reductions in the size and power use of battery-powered mobile computers, allowing further rapid progress in mobile sensors, computing, and controls.

The paper documenting the work to be summarized in this talk is Koomey, Jonathan G., Stephen Berard, Marla Sanchez, and Henry Wong. 2011. "Implications of Historical Trends in The Electrical Efficiency of Computing." IEEE Annals of the History of Computing. vol. 33, no. 3. July-September. pp. 46-54.

Clean Energy: The Intersection of Technology, Policy and Finance

Dan Reicher, Steyer-Taylor Center for Energy Policy and Finance, Stanford University

Monday, October 24, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

The talk will focus on the "clean energy triangle" -- technology, policy and finance -- with a particular emphasis on the role that policy and finance have in driving the development and deployment of a broad array of clean energy technologies, from efficiency and renewables to advanced fossil and nuclear. This will include a discussion of the "Valley of Death" -- the looming chasm that often sits between the early government and venture-funded development of an energy technology and its full-scale commercial deployment. The talk will also cover the important intersection between energy technology and information technology and the current stalemate in energy policy in Washington, D.C.

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California's Energy Future Study: Portraits of the Energy System in 2050

Jane Long, Lawrence Livermore National Laboratory

Monday, October 17, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

The California Council on Science and Technology has undertaken a study of California's energy system in 2050. By executive order, the state is to reduce emissions to 80% below 1990 levels by 2050. The study identifies energy system descriptions (call "portraits") from a technical perspective that would meet this standard and allow for population and economic growth. The requirement for growth means that the energy system should have nearly zero emissions. The portraits are constructed by evaluating four key questions: How much can we control demand? How much heat and transportation will be electrified? How will electricity be de-carbonized? How much sustainable biofuel could be available? Results show an energy system that dramatically different than today, but largely relies on technology we know about.

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Solar Energy Mini-Series: Suntech -- Empowering a Solar Tomorrow

Zhengrong Shi, Chief Executive Officer, Suntech Power Holdings Co., Ltd.

Monday, October 17, 2011 | 12:15 PM - 01:30 PM | Bechtel Conference Center, Encina Hall | Free and Open to All

Please note different time and location. 12:15-1:30pm at Bechtel Conference Center, Encina Hall

With a quarter of the world’s population in developing countries without access to basic electricity, solar energy is the panacea for solving the energy crisis that affects us today. Through years of research, solar technology has now reached the point where it can be deployed in terms of scale and cost to fundamentally change the way we generate electricity. Suntech, which celebrates its 10th anniversary this year, has been instrumental in driving the growth of the solar energy industry around the world.

Helmed by the eminent solar scientist, Dr. Zhengrong Shi, Suntech has made great strides in reducing the cost of harnessing solar energy and increasing the performance of solar cells. Its crystalline silicon cells are among the world’s most efficient, and the company has broken multiple world records for leading conversion efficiency on mono-crystalline and multicrystalline substrates. In the past 10 years, Suntech has installed more than 15 million panels in more than 80 countries on all continents. Central to Suntech’s success is its ability to push solar technology to the next level.

With less than 1% of the world’s energy production coming from solar, Suntech remains focused in revolutionizing the global energy industry.

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Solar Energy Mini-Series: Solar PV Manufacturing -- U.S. Competitiveness in a Global Industry

Alan Goodrich, National Renewable Energy Laboratory

Monday, October 10, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

Over the past five years, solar Photovoltaic (PV) module shipments from China and Taiwan has grown from 6% to 54% global market share, while the U.S. has slipped from 9% to 6% market share. Chinese PV companies have gained an international pole position, in part, by achieving the industry’s lowest silicon module manufacturing cost. There is also a clear strategic effort on the part of the Chinese government to drive an expansion into the high technology enterprises of the future, like solar PV by offering strong state support for export industries such as solar PV component manufacturing. Over the long term, however, there are many challenges facing the Chinese PV industry that will impact its ability to sustain its dominant position.

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American Public Opinion on Climate Change and Its Impact on Voting in Congressional and Presidential Elections: New Evidence from State and National Surveys

Jon Krosnick, Department of Communication, Stanford University

Monday, October 3, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

In recent years, observers have speculated that the American public has become increasingly skeptical about the existence and potential threat of climate change and that the public desire for action by government on this issue has declined. In this talk, Jon Krosnick will present new survey evidence tracking public opinion in the nation and in Massachusetts to explore what changes have occurred in the entire population and in population subgroups. In addition, Dr. Krosnick will present the results of a new study examining whether candidates' positions on climate change policy have influenced their electoral success, using three methods of investigation: (1) analysis of the relation of candidate website statements on climate with the victory rates of Congressional candidates in 2010, (2) experiments embedded in surveys describing a hypothetical candidate running for a Senate seat, and (3) a statistical analysis predicting votes in the 2008 U.S. Presidential election using data collected from survey respondents before and after the election. The findings paint a portrait of the likely role of climate change in the upcoming elections.

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Solar Energy Mini-Series: The Opto-Electronic Physics That Just Broke the Efficiency Record in Solar Cells

Eli Yablonovitch, Electrical Engineering & Computer Sciences Dept., University of California-Berkeley

Monday, September 26, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

The solar cell field is changing. We are finally approaching the Shockley-Queisser (SQ) limit for single junction solar cell ~33.5% efficiency under the standard solar spectrum. Previously, the record had been stuck at 25.1%, during 1990-2007. Why then the 8% discrepancy between the theoretical limit 33.5% versus the previously achieved efficiency?

It is usual to blame material quality. But in the case of GaAs double heterostructures, the material is almost ideal with an internal fluorescence yield of >99%. This deepens the puzzle as to why the full theoretical SQ efficiency was not achieved?

Counter-intuitively, efficient external fluorescence is a necessity for approaching the ultimate limits. Now new efficiency records are being broken. Alta Devices has reached 28.2%. A great Solar Cell also needs to be a great Light Emitting Diode.

Scenarios of the Global Climate Energy System

Keywan Riahi, Senior Research Scholar and Acting Leader of the Energy Program, International Institute for Applied Systems Analysis (IIASA)

Monday, May 23, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

More than 300 energy experts collaborated over the last four years on the Global Energy Assessment (GEA). The Report, forthcoming in Summer 2011, aims at providing the technical and scientific basis for the evaluation of social, economic, technological, and environmental challenges linked to energy. This talk focuses on findings of the GEA energy scenario analysis. The scenarios explore transformative changes of the energy system in order to meet a range of sustainability objectives. Specifically, they assesses technical measures, policies, and related costs and benefits for providing almost universal access to affordable clean cooking fuel and electricity for the poor, limiting air pollution and health damages from energy use, improving energy security throughout the world, and limiting climate change to below 2C compared to preindustrial levels. Results from the scenario analysis indicate that the transformation towards ambitious sustainability objectives is technically possible, and that alternative combinations of resources, technologies, and policies are conceivable to attain the objectives. Three illustrative pathways (GEA-Supply, GEA-Mix, and GEA-Efficiency) are selected from a large ensemble of possible transformations. They depict salient branching points for policy implementation and highlight different degrees of freedom and routes to the sustainability objectives.

Powering the World for all Purposes With Wind, Water, and Sunlight

Mark Z. Jacobson, Department of Civil & Environmental Engineering, Stanford University

Monday, May 16, 2011 | 04:15 PM - 05:15 PM | NVIDIA Auditorium, Jen-Hsun Huang Engineering Center | Free and Open to All

This talk discusses a plan to power 100% of the world’s energy for all purposes with wind, water, and sunlight (WWS) within the next 20-40 years. The talk starts by reviewing and ranking major proposed energy-related solutions to global warming, air pollution mortality, and energy security while considering other impacts of the proposed solutions, such as on water supply, land use, resource availability, reliability, wildlife, and catastrophic risk. It then evaluates a scenario for powering the world on the energy options determined to be the best while also considering materials, transmission infrastructure, costs, and politics. The study concludes that powering the world with wind, water, and solar technologies, which are found to be the best when all factors are considered, is technically feasible but politically challenging. Relevant papers can be found at http://www.stanford.edu/group/efmh/jacobson/Articles/I/susenergy2030.html.

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The Graduate School of Business' Knight Management Center: LEED + PV

Kathleen Kavanaugh, Program Director, Stanford Graduate School of Business

Bhima Sheridan, Jon Biegenzahn, and Ben Tarbell, Solar City 

Wednesday, May 11, 2011 | 04:15 PM - 05:15 PM | | Free and Open to All

Please note different time and location: Wednesday 5/11, 4:15-5:15pm at Knight Management Center C106

 

An interactive presentation on the design and implementation of the Graduate School of Business' goals for sustainability at it's new Knight Management Center campus.  Kathleen Kavanaugh, LEED AP and Program Director at the Knight Management Center will discuss the vision for the campus, which is seeking LEED Platinum certification from the United States Green Building Council.  Bhima Sheridan will talk about Solar City's approach to engineering the photovoltaic system and integrating it with the building's energy efficient design.  Jon Biegenzahn will talk about the project development process at Stanford including construction coordination challenges and involving campus stakeholders.

 

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