Global Energy Perspective

• Present Primary Power Mix

• Future Constraints Imposed by Sustainability

• Theoretical and Practical Energy Potential of Various Renewables

• Challenges to Exploit Renewables Economically on the Needed Scale

Nathan S. Lewis, California Institute of TechnologyDivision of Chemistry and Chemical Engineering

Pasadena, CA 91125http://nsl.caltech.edu

Mean Global Energy Consumption, 1998

4.52

2.7 2.96

0.286

1.21

0.2860.828

00.5

11.5

22.5

33.5

44.5

5

TW

Oil Coal Biomass NuclearGas Hydro Renew

Total: 12.8 TW U.S.: 3.3 TW (99 Quads)

US Energy Flow -1999Net Primary Resource Consumption 102 Exajoules

Energy From Renewables, 1998

10-5

0.0001

0.001

0.01

0.1

1

Elect Heat EtOH Wind Solar PVSolar Th.Low T Sol HtHydro Geoth Marine

Renewables

B

Elec Heat EtOH Wind Sol PV SolTh LowT Sol Hydro Geoth Marine

TW

Biomass

5E-5

1E-1

2E-3

1E-4

1.6E-3

3E-1

1E-2

7E-5

(in the U.S. in 2002)

1-4 ¢ 2.3-5.0 ¢ 6-8 ¢ 5-7 ¢

Today: Production Cost of Electricity

0

5

10

15

20

25

Coal Gas Oil Wind Nuclear Solar

Cost6-7 ¢

25-50 ¢

Cos

t , ¢

/kW

-hr

Energy Costs

0

2

4

6

8

10

12

14

$/GJ

Coal Oil Biomass Elect

Bra

zil E

urop

e

$0.05/kW-hr

www.undp.org/seed/eap/activities/wea

Energy Reserves and Resources

020000400006000080000

100000120000140000160000180000

(Exa)J

OilRsv

OilRes

GasRsv

GasRes

CoalRsv

CoalRes

UnconvConv

Reserves/(1998 Consumption/yr) Resource Base/(1998 Consumption/yr)

Oil 40-78 51-151Gas 68-176 207-590Coal 224 2160

Rsv=ReservesRes=Resources

• Abundant, Inexpensive Resource Base of Fossil Fuels

• Renewables will not play a large role in primary power generation unless/until: technological/cost breakthroughs are achieved, or unpriced externalities are introduced (e.g., environmentally

-driven carbon taxes)

Conclusions

• “It’s hard to make predictions, especially about the future”

• M. I. Hoffert et. al., Nature, 1998, 395, 881, “Energy Implications of Future Atmospheric Stabilization of CO2 Content

adapted from IPCC 92 Report: Leggett, J. et. al. in Climate Change, The Supplementary Report to theScientific IPCC Assessment, 69-95, Cambridge Univ. Press, 1992

Energy and Sustainability

Population Growth to 10 - 11 Billion People in 2050

Per Capita GDP Growthat 1.6% yr-1

Energy consumption perUnit of GDP declinesat 1.0% yr -1

1990: 12 TW 2050: 28 TW

Total Primary Power vs Year

M. I. Hoffert et. al., Nature, 1998, 395, 881

Carbon Intensity of Energy Mix

Data from VostokIce Core

CO2 Emissions

Projected Carbon-Free Primary Power

• “These results underscore the pitfalls of “wait and see”.”

• Without policy incentives to overcome socioeconomic inertia, development of needed technologies will likely not occur soon enough to allow capitalization on a 10-30 TW scale by 2050

• “Researching, developing, and commercializing carbon-free primary power technologies capable of 10-30 TW by the mid-21st century could require efforts, perhaps international, pursued with the urgency of the Manhattan Project or the Apollo Space Program.”

Hoffert et al.’s Conclusions

• If we need such large amounts of carbon-free power, then:

• current pricing is not the driver for year 2050 primary energy supply

• Hence,

• Examine energy potential of various forms of renewable energy

• Examine technologies and costs of various renewables

• Examine impact on secondary power infrastructure and energy utilization

Lewis’ Conclusions