Energy Options for the Future phần 3 pdf

Energy efficiency concepts include:

Conservation: behavioral changes that reduce

energy use.

Energy efficiency: permanent changes in

equipment that result in increased energy

services per unit of energy consumed.

Economic potential for energy efficiency: the

technically feasible energy efficiency mea￾sures that are cost-effective. This potential

may not be exploited because of market fail￾ures and barriers.

During the past century world energy consump￾tion has grown at a 2% annual rate. If this rate were

to continue, there would be a need for 7 times more

energy per year in 2100. In the U.S. the energy

consumption is growing at a 1–1.5% annual rate. At

the 1% level this would lead to a 28% increase by

2025 and 2.7 times increase by 2100. If the energy mix

remains the same, this will lead to a growing shortfall

and increasing imports.

In the U.S. 39% of energy consumption is in

residential and commercial buildings, 33% in indus￾try, and 28% in transportation. Numerous studies

have been made by groups of DOE’s laboratories of

the potential for improved energy efficiency [Scenar￾ios of U.S. Carbon Reduction (1997) (www.ornl.gov/

Energy_Eff), Technology Opportunities to Reduce

U.S. Greenhouse Gas Emissions (1998) (www.ornl.-

gov/climate_change/climate.htm), Scenarios for a

Clean Energy Future (2000) (www.ornl.gov/ORNL/

Energy_Eff/CEF.htm and Energy Policy, Vol. 29, No

14, Nov. 2001)].

Implementing Current Technologies

In ‘‘California’s Secret Energy Surplus: The

Potential for Energy Efficiency’’ by Rufo and Coito

(2002: www.Hewlett.org) it is estimated that Califor￾nia has an economic energy savings potential of 13%

of base electricity usage in 2011 and 15% of total base

demand in 2011.

Similarly, in ‘‘Natural Gas Price Effects of

Energy Efficiency and Renewable Energy practices

and Policies’’ by Elliott et al., Am, Council for an

Energy Efficient economy (2003: http://acee.org) it is

estimated that the U.S. could reduce electricity

consumption by 3.2% and natural gas consumption

by 4.1%.

Inventing and Implementing New Technology

Estimates have been made of the upper limits on

the attainable energy efficiency for non-electric uses,

by 2100, of 232% for residential energy consumption

and 119% for industry—‘‘Technology Options’’ for

the Near and Long Term (2003) (www.climate.tech￾nology.gov), and ‘‘Energy Intensity Decline Implica￾tions for Stabilization of Atmospheric CO2 content

by H,’’ by Lightfoot and Green (2002) (www.mcg￾ill.ca/ccgcr/). The goal of the study ‘‘Scenarios for a

Clean Energy Future’’ was ‘‘to identify and analyze

policies that promote efficient and clean energy

technologies to reduce CO2 emissions and improve

energy security and air quality.’’

The following U.S. energy policies were consid￾ered in the ‘‘advanced scenario’’:

g

Fig. 17. The model predicts that production may peak before proved reserves (caveat).

Energy Options for the Future 83