GCEP Symposium 2009

New Research Directions in a Rapidly Evolving Global Energy Landscape

Sally Benson, Director GCEP

Opening Remarks

• Goal: How do we meet the growing needs of energy while protecting the planet?

• GCEP Sponsors
  • ExxonMobil
  • Toyota
  • Schulumerger
  • GE

• GCEP Mission
  • Research on low-greenhouse gas emissions energy conversions
  • Focus on fundamental and pre-commercial research
  • Applications in the 10-50 years timeframe
• GCEP Projects
  
  • $119 Million in funding
  • 66 full-term research programs
  • 21 explatory research activities
• GCEP Web site

 

Michal P. Rmage, ExxonMobil
Jim Sweeny, Stanford

Liquid Transportation Fuels from Coal and Biomass

• Online Report
• 500 million tons of biomass will be avaiable by 2020 in US that is sustainable and won't impact food or increase CO2
• 2-3 mbpd of oil equivalent fuels can be produce by 2035 from coal and biomass

 

Kevin Tomsovic, U Tennessee
Tom, U Illinois

New Grid Controls to Enable Renewable Generation

• (290k GWh of pumped storage)
• Challenge: assume 50% renewables
  • Less predictable
  • Far from load centers
  • Don't match daily load cycle
  • Unusual operating constraints: rapid variation, complicated weather dependence
  • Needs tight coupling to storage, which may be mobile
•  Current system problems:
  
  • Largely hierarchical and centralized
  • Controls separated by time frame and reach
  • Most communication flows up to control center (little from substation to substation)
  • Pricing driven mostly by generation scheduling considerations
  • Little customer choice in level of reliability (consumers don't all need high levels of reliability and would be willing to pay less for slightly less reliability)
  • System design mandated mostly by reliability
  • Existing system can't be adjusted incrementally easily because of scalability issues
  • Controlled entities (generators) are assumed to be in hundreds, not millions
• Needed system changes
  • Broader electric grid definition to include end energy use
  • Increased scheduling capability through load management
  • New transmission
  • Effective storage
  • A flattening of control structures
• Real-world example of power outage
• Electrons are not currently controlled on the lines. The power creation is controlled then they just flow over the lines where they will
• They are working on system to change impedance in lines to control their flow.
• If we can control load, we can integrate more renewables. Perfect app for EVs
• 2007 Presentation

 

Chris Edwards, Stanford

Advanced Combustion

• 74% of US Co2 is emitted by engines: 34% from transportation, 40% from electricity generation
• 4 ways to transfer energy: heat, work matter, radiation
• 100 to 1 compression can cut entropy loses in half and boost efficiencies to 60%
• Post combustion pressue needs to go to 1000 bar, way over what is normal. So it must be fast and balanced.
• Free piston engines
  • Normal speeds for F1 cars are 25 ms, there are 60 to 100 ms.
  • Wants to hit 60% efficiencies - this is single cycle
• Optimal ratio of combustion energy to pressure loses is 200 to 1.

 

Yi Cui, Stanford

Nanostructures in Solar Cells and Advanced Batteries

Nanostructures in Solar Cells

• Nanocone solar cells: anti-reflective (looks black), light trapping, thinner and lower cost
• After depositing PV materials, becomes a nanodome.
• Has 5.9% efficiency versus 4.7% for a-Si think-film PV
• Should work for poly-Si and CIGS too

Nanostructured Batteries

• Energy density is pretty much determined by materials
• Anode: Graphite. Cathode: LiCoO2, LiMn2O4, LiFeO4

Anodes

• Graphiite: C6 <-> LiC6 and very little structure change, less than 10%
• Silicon anode: Si <-> Li4.4 Si holds more energy. However 300% expansion
• Silicon Nanowires (SiNW):
  • large surface area dn shorter distance for Li iddufsion (High power)
  • Good strain release and interface control (better cycle life)
  • Continuous electon transport pathway (hih power)
  • 10 times higher capacity than the existing carbon anodes
  • Much better cycle life
• Have gone to 300 cycles
• Si goes from crystaline to amorphous after a few cycles
• If amorphous shell surrounds cystaline core it proves stable mechanical support and efficient electron transport
• Use carbon nanofiber as core

Cathodes

• Cathodes are more limiting part of the battery, want high potential
• Li metal-Sulfur has 10 times the potential energy
• Challenges
  • Large structure change and volume expansion
  • S and Li2S are electronically insulating
  • The intermedia phase (lithium polysulfide) is soluble in electrolyte
  • Li metal is dangerous
• Mesoporous Carbon-Sulfur composite cathodes

Full battery

• Full battery uses Si Nanowire anodes and Li2S cathodes
• Theoretical 4 times more specific energy, lab is showing 50% more

 

Nate Lewis, Caltech

Basic Research Needs in Solar Energy Utilization

• Basic Research Needs for Solar Energy Utilization
• The sun is a singular solution to our future enegy needs, but the gap between our tin use and potential is immense
• More energy from sun reaches the earth than we use in a year
• Current power used 13 TW. Need 14 TW of additional power by 2050, 33 TW by 2100
• To reach independence with nuclear, need to build 1 new 1Gw reactor every day for 38 years
• PV generate less than 0.1% of electricity and %0.01 of total energy
• Competitive electric power is $0.40/Wp = $0.02/kWh. Competitive primary power is half this
• Deploy 1 million solar roof installation every day to get to scale
• Paint, carpet and newspaper only goods that are produced at this rate.
• We know that multiple junction PV works, but it is too expense
• New technologies are: multiple gaps, multiple excitons per photon, hot carriers
• Plants are failed technology - less than 1% efficient

 

Jeff Keller, External Technology Initiatives at GE's Global Research

Technological Innovation: The Cornerstone of Value

What is need to catchup on Greentech?

• Long-term market signal to show US values low-carbon enrgy
• Clear rules for utilies
• Energy standards that grow over time
• Wind needs Production Tax Credits (PTC) in order to be viable. Volatility of PTC dampens growth.

Booz & Co: The Mobility Threshold

 

John Deutch, MIT

Accelerating Energy Innovations – What is Important and What is Not

• 4 Point of Discovery and Application
  • Point 1: Huge shift in in innovation paradigm to parallel model of research and development (science and engineering)
  • Point 2: Most difficult step is demonstration of practicality of technology
  • Point 3: Department of Energy has not been particularly successful
  • Point 4: Change in paradigm has big implications for how universities pursue research

 

Mark Wrighton, Chancellor, Washington University in St. Louis

America’s Energy Future: Technology Opportunites, Risks, and Tradeoffs

• Repots at: http://www.nationalacademies.org/energy
• “Conservation” is modifying behavior, “Efficiency” is not
• The deployment of existing energy-efficiency technologies is the nearest-term and lowest-cost option for moderating our nation’s demand for energy.
• Could save 840 TWh by 2020 in electricity savings in commercial and residential buildings, and 1,300 TWh by 2030, rather than increasing by 3,200 and 3,700 respectively
• Arch coal pulls a train 35-miles long every day to provide its power source
• Modernizing the grid: $175 billion for expansion and $50 billion for modernization of the transmission system, and $470 billion for expansion and $170 billion for modernization of the distribution system.