A. Shakouri 2/11/2009
Can Renewables Save the
World?
Ali Shakouri
Baskin School of Engineering
University of California Santa Cruz
http://quantum.soe.ucsc.edu/
UCSC Silicon Valley Center/NASA Ames; 11 February 20091

World Marketed Energy Use by A. Shakouri 2/11/2009
Fuel Type 1980-2030 2050: 25-30TW
13TW
34%
28%
38%
24%
26% Share of
World
Total
23%
8%
7%
6%
6%
DOE Energy Information Administration (2007) 2
2

US Energy Consumption A. Shakouri 2/11/2009
3

A. Shakouri 2/11/2009
Martin Green, UNSW
4

Cost of Renewable Energy A. Shakouri 2/11/2009
Levelized cents/kWh in constant $2000
100
40
PV
Wind
COE cents/kWh
COE cents/kWh
80
30
60
20
40
10 20
0
0
1980 1990 2000 2010 2020 1980 1990 2000 2010 2020
70 15
10
Solar thermal Biomass
Geothermal
COE cents/kWh
60
COE cents/kWh
COE cents/kWh
8 12
50
9
6 40
30 6
4
20
3
2 10
0
0
0
1980 1990 2000 2010 2020 1980 1990 2000 2010 2020 1980 1990 2000 2010 2020
Source: NREL Energy Analysis Office
Keith Wipke, NREL
These graphs are reflections of historical cost trends NOT precise annual historical data.
Updated: October 2002
5

Microprocessor Evolution A. Shakouri 2/11/2009
1 Billion
K
1,000,000 Transistors
100,000
Pentium® 4
Pentium® III
10,000 Pentium® II
Pentium®
1,000
i486
i386
100 80286
8086
10
1
’75 ’80 ’85 ’90 ’95 ’00 ’05 ’10 ’15
6

Airplane Speed/Efficiency Evolution A. Shakouri 2/11/2009
US Energy Intensity (MJ)
Airplane Speed
per available seat km
@ 160kg payload/seat
NLR-CR-2005-669;Peeters P.M., Middel
McMasters & Cummings, Journal of
J., Hoolhorst A.
Aircraft, Jan-Feb 2002
7

A. Shakouri 2/11/2009
Felix’s
forecasts of
Nuclear
US energy
consumption
Natural
in year 2000
gas
(early 1970’s)
Oil
Coal Vaclav Smil,
Energy at the Crossroads,
2005
8

A. Shakouri 11/25/2008
A. Shakouri 2/11/2009
Nate Lewis, Caltech 9

A. Shakouri 2/11/2009
Amount of land
needed for 20 TW at
1% efficiency:
9% of land
Chris Somerville, UC Berkeley 10

Biofuels A. Shakouri 2/11/2009
Dan Kammen, Berkeley 11

Solar Energy Potential A. Shakouri 2/11/2009
12 TW
2.0-2.9
4.0-4.9
6.0-6.9
12

Energy Storage Options A. Shakouri 2/11/2009
Specific Power (W/kg)
Combustion
Engine
Specific Energy (Wh/kg)
13

A. Shakouri 2/11/2009
Vaclav Smil
Energy at the
Crossroads
14

Power ~3.3TW
A. Shakouri 11/25/2008
A. Shakouri 2/11/2009
Rejected
1.3TW
Energy 61%
Lawrence Livermore National Lab., http://eed.llnl.gov/flow
15

Can Renewables Save the World? A. Shakouri 2/11/2009
• Fossil fuels have excellent energy characteristics.
• Wind/ geothermal are among the cheapest of
renewables. There is potential for significant
growth but they can not solve our energy problem.
• Solar energy has the potential to provide all our
energy needs.
– Currently expensive; it is intermittent.
• Currently no clear options for large scale energy
storage
• Biomass has the potential to provide part of
transportation energy needs
– Cellulosic biofuels and algaes are interesting but they
have not demonstrated large scale/long term potential.
One has to consider the full ecosystem impact (water,
food, etc.).
16

A. Shakouri 2/11/2009
World Average
John Bowers, UCSB 17

Can Renewables Save the World? A. Shakouri 2/11/2009
• If our goal is to have a planet where everybody has
a level of life similar to developed countries, energy
need is enormous and it is not clear if we can do this
by working on the supply side alone.
• Energy efficiency is helpful but it is not enough.
• We need to consider changes in lifestyle, city
planning and social structure (transportation,
lodging, grid).
18

Plan B for Energy A. Shakouri 2/11/2009
September 2006; Scientific American; W. Wayt Gibbs
• WAVES AND TIDES (Reality factor 5)
• HIGH-ALTITUDE WIND (Reality factor 4)
• NANOTECH SOLAR CELLS (Reality factor 4)
• DESIGNER MICROBES (Reality factor 4)
• NUCLEAR FUSION (Reality factor 3)
• SPACE-BASED SOLAR (Reality factor 3)
• A GLOBAL SUPERGRID (Reality factor 2)
• SCI-FI SOLUTIONS (Reality factor 1)
– Cold Fusion and Bubble Fusion
– Matter-Antimatter Reactors
19

EE80J Renewable Energy Sources
Spring 2009, Also Summer 2009 A. Shakouri 2/11/2009
• Energy, power and thermodynamics
• Home energy audit
• Power plants, nuclear power
• Solar energy
• Wind energy, hydropower, geothermal
• Biomass, hydrogen, fuel cells
• Economics, Environmental and
Societal Impacts
EE181J Renewable Energies in
Practice (July-August 2009)
CA/Denmark summer school (UCSC,
UC Davis, UC Merced, Techn. Univ.
Denmark, Roskilde)
UCSC Courses 20