Photo: Lawrence Berkeley National Laboratory |
As China’s
economy continues to soar, its energy use and greenhouse gas emissions will
keep on soaring as well—or so goes the conventional wisdom. A new analysis by
researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) now is
challenging that notion, one widely held in both the United
States and China.
Well before mid-century, according to a new study by Berkeley Lab’s China
Energy Group, that nation’s energy use will level off, even as its population
edges past 1.4 billion. “I think this is very good news,” says Mark Levine,
co-author of the report, “China’s
Energy and Carbon Emissions Outlook to 2050,” and director of the group. “There’s been a perception that China’s
rising prosperity means runaway growth in energy consumption. Our study shows
this won’t be the case.”
Along with China’s
rise as a world economic power have come a rapid climb in energy use and a
related boost in man-made carbon dioxide emissions. In fact, China overtook the United States in 2007 as the
world’s leading emitter of greenhouse gases.
Yet according to this new forecast, the steeply rising curve of energy
demand in China
will begin to moderate between 2030 and 2035 and flatten thereafter. There will
come a time—within the next two decades—when the number of people in China acquiring
cars, larger homes, and other accouterments of industrialized societies will
peak. It’s a phenomenon known as saturation. “Once nearly every household owns
a refrigerator, a washing machine, air conditioners and other appliances, and
once housing area per capita has stabilized, per household electricity growth
will slow,” Levine explains.
Similarly, China
will reach saturation in road and rail construction before the 2030 to 2035
time frame, resulting in very large decreases in iron and steel demand.
Additionally, other energy-intensive industries will see demand for their
products flatten.
The Berkeley Lab report also anticipates the widespread use of electric
cars, a significant drop in reliance on coal for electricity generation, and a
big expansion in the use of nuclear power—all helping to drive down China’s CO2
emissions. Although China
has temporarily suspended approvals of new nuclear power plant construction in
the wake of the disaster at Japan’s
Fukushima Daiichi Nuclear Power Station, the long-range forecast remains
unchanged.
Key to the new findings is a deeper look at patterns of energy demand in China: a “bottom-up” modeling system that develops projections of energy use in far
greater detail than standard methods and which is much more time- and labor-intensive
to undertake. Work on the project has been ongoing for the last four years. “Other studies don’t have this kind of detail,” says Levine. “There’s no model
outside of China
that even comes close to having this kind of information, such as our data on
housing stock and appliances.”
Not only does the report examine demand for appliances such as refrigerators
and fans, it also makes predictions about adoption of improvements in the
energy efficiency of such equipment—just as Americans are now buying more
efficient washing machines, cars with better gas-mileage, and less power-hungry
light bulbs.
Berkeley Lab researchers Nan Zhou, David Fridley, Michael McNeil, Nina
Zheng, and Jing Ke co-authored the report with Levine. Their study is a “scenario analysis” that forecasts two possible energy futures for China, one an “accelerated improvement scenario” that assumes success for a very aggressive
effort to improve energy efficiency, the other a more conservative “continued
improvement scenario” that meets less ambitious targets. Yet both of these
scenarios, at a different pace, show similar moderation effects and a
flattening of energy consumption well before 2050.
Under the more aggressive scenario, energy consumption begins to flatten in
2025, just 14 years from now. The more conservative scenario sees energy
consumption rates beginning to taper in 2030. By the mid-century mark, energy
consumption under the “accelerated improvement scenario” will be 20% below that
of the other.
Scenario analysis is also used in more conventional forecasts, but these are
typically based on macroeconomic variables such as gross domestic product and
population growth. Such scenarios are developed “without reference to
saturation, efficiency, or usage of energy-using devices, e.g., air
conditioners,” says the Berkeley Lab report. “For energy analysts and
policymakers, this is a serious omission, in some cases calling into question
the very meaning of the scenarios.”
The new Berkeley Lab forecast also uses the two scenarios to examine CO2
emissions anticipated through 2050. Under the more aggressive scenario, China’s
emissions of the greenhouse gas are predicted to peak in 2027 at 9.7 billion
metric tons. From then on, they will fall significantly, to about 7 billion metric
tons by 2050. Under the more conservative scenario, CO2 emissions
will reach a plateau of 12 billion metric tons by 2033, and then trail down to
11 billion metric tons at mid-century.
Several assumptions about China’s
efforts to “decarbonize” its energy production and consumption are built into
the optimistic forecasts for reductions in the growth of greenhouse gas
emissions. They include:
- A dramatic reduction in
coal’s share of energy production, to as low as 30% by 2050, compared to
74% in 2005 - An expansion of nuclear power
from 8 gigwatts in 2005 to 86 gigawatts by 2020, followed by a rise to as
much as 550 gigawatts in 2050 - A switch to electric cars.
The assumption is that urban private car ownership will reach 356 million
vehicles by 2050. Under the “continued improvement scenario,” 30% of these
will be electric; under the “accelerated improvement scenario,” 70% will
be electric.
The 72-page report by Levine and colleagues at Berkeley Lab’s Environmental
Energy Technologies Division was summarized in a briefing to U.S.
Congressional staffers. The study was carried out under contract with the U.S.
Department of Energy, using funding from the China Sustainable Energy Program,
a partnership of the David and Lucile Packard Foundation and the Energy
Foundation.