October 25, 2012
The Great Transition, Part I: From Fossil Fuels to Renewable Energy
Lester R. Brown
The great energy transition from fossil fuels to renewable
sources of energy is under way. As fossil fuel prices rise, as oil
insecurity deepens, and as concerns about pollution and climate
instability cast a shadow over the future of coal, a new world
energy economy is emerging. The old energy economy, fueled by oil,
coal, and natural gas, is being replaced with an economy powered by
wind, solar, and geothermal energy. The Earth’s renewable energy
resources are vast and available to be tapped through visionary
initiatives. Our civilization needs to embrace renewable energy on a
scale and at a pace we’ve never seen before.
We inherited our current fossil fuel based world energy economy
from another era. The 19th century was the century of coal, and oil
took the lead during the 20th century. Today, global emissions of
carbon dioxide (CO2)—the principal climate-altering
greenhouse gas—come largely from burning coal, oil, and natural gas.
Coal, mainly used for electricity generation, accounts for 44
percent of global fossil-fuel CO2 emissions. Oil, used
primarily for transportation, accounts for 36 percent. Natural gas,
used for electricity and heating, accounts for the remaining 20
percent. It is time to design a carbon- and pollution-free energy
economy for the 21st century.
Some trends are already moving in the right direction. The
burning of coal, for example, is declining in many countries. In the
United States, the number two coal consumer after China, coal use
dropped 14 percent from 2007 to 2011 as dozens of coal plants were
closed. This trend is expected to continue, due in part to
widespread opposition to coal now being organized by the Sierra
Club’s Beyond
Coal campaign.
Oil is used to produce just 5 percent of the world’s electricity
generation and is becoming ever more costly. Because oil is used
mainly for transport, we can phase it out by electrifying the
transport system. Plug-in hybrid and all-electric cars can run
largely on clean electricity. Wind-generated electricity to operate
cars could cost the equivalent of 80-cent-per gallon gasoline.
As oil reserves are being depleted, the world has been turning
its attention to plant-based energy sources. Their potential use is
limited, though, because plants typically convert less than 1
percent of solar energy into biomass.
Crops can be used to produce automotive fuels, such as ethanol
and biodiesel. Investments in U.S. corn-based ethanol distilleries
became hugely profitable when oil prices jumped above $60 a barrel
following Hurricane Katrina in 2005. The investment frenzy that
followed was also fueled by government mandates and subsidies. In
2011, the world produced 23 billion gallons of fuel ethanol and
nearly 6 billion gallons of biodiesel.
But the more research that’s done on liquid biofuels, the less
attractive they become. Every acre planted in corn for ethanol means
pressure for another acre to be cleared elsewhere for crop
production. Clearing land in the tropics for biofuel crops can
increase greenhouse gas emissions instead of reducing them. Energy
crops cannot compete with land-efficient wind power.
The scientific community is challenging the natural gas
industry’s claim that its product is fairly climate-benign. Natural
gas produced by hydraulic fracturing, or fracking (a much-touted key
to expanding production) is even more climate-disruptive than coal
because of methane gas leakage. (Methane is a potent contributor to
climate change.)
The last half of the twentieth century brought us nuclear power,
once widely touted as the electricity source of the future. Although
nuclear reactors supply 13 percent of the world’s electricity,
nuclear power’s limited role in our future has been clear for some
time. It is simply too expensive.
Countries around the world are richly endowed with renewable
energy, in some cases enough to easily double their current
electrical generating capacities. A revamped clean energy economy
will harness more energy from the wind and sun, and from within the
Earth itself. Climate-disrupting fossil fuels will fade into the
past as countries turn to clean, climate-stabilizing, nondepletable
sources of energy. The growth in the use of solar cells that convert
sunlight into electricity can only be described as explosive,
expanding by 74 percent in 2011. Early photovoltaic (PV)
installations were all small-scale—mostly on residential rooftops.
That’s changing as more utility-scale PV projects are being
launched. The United States, for example, has under construction and
development more than 100 utility scale projects. Solar-generated
electricity is particularly attractive in desert regions such as the
U.S. Southwest because peak generation meshes nicely with peak air
conditioning use.
The world’s current 70,000 megawatts of photovoltaic
installations can, when operating at peak power, match the output of
70 nuclear power plants. With PV installations climbing and with
costs continuing to fall, cumulative PV generating capacity could
surpass 1 million megawatts in 2020. (Current world electricity
generating capacity from all sources is 5 million megawatts.)
Installing solar panels for individual homes in the villages of
developing countries is now often cheaper than it is to supply them
with electricity by building a central power plant and a grid.
The heat that comes from within the Earth—geothermal energy—can
be used for heating or converted into steam to generate electricity.
Many countries have enough harnessable geothermal energy to satisfy
all of their electricity needs. Despite this abundance, the
geothermal energy capacity installed as of 2012 is only enough to
provide electricity for some 10 million homes worldwide.
Roughly half of the world’s 11,000 megawatts of installed
geothermal generating capacity is concentrated in the United States
and the Philippines. Altogether, 24 countries now convert geothermal
energy into electricity. The United States, with 130 confirmed
geothermal plants under construction or in development, will be
bringing at least 1,000 megawatts of generating capacity online in
the near term. Worldwide, this accelerating pace could yield 200,000
megawatts of generating capacity by 2020.
Each alternative energy source—whether
solar,
geothermal, or
wind—has a major role to play, but it is wind that is on its way
to becoming the foundation of the new energy economy.
Stay tuned for more discussion of the advantages and potential of
wind energy in
Part II.
Adapted from “Exciting
News About Renewable Energy,” by Lester R. Brown, in the
October/November 2012 issue of
Mother
Earth News.
Lester R. Brown is President of Earth Policy Institute and author
of
Full Planet, Empty Plates: The New Geopolitics of Food Scarcity.