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Speculation about dwindling oil supplies and concern about the increasingly
detrimental effects of climate change have pushed renewable energies to the
forefront of U.S. energy-policy plans. As a result, the United States may derive
a larger share of its energy and electricity from renewables, such as wind power,
in the years ahead. However, the rise of renewables will not be as rapid as
many believe, and fossil fuels and uranium[16] will
continue to supply the bulk of our energy and electricity in the near term.
It’s worth looking at the current and projected future contributions from
renewable energy sources—as well as the widespread public misconceptions
about them.
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Given our abundance
of fossil fuels and uranium, their dominance in our
nation’s electricity supply—they collectively
accounted for just over 91 percent of U.S. electricity
generation in 2007—is not surprising. The EIA projects
that these fuels will still account for 85 percent of
our total electric generation in 2030.
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Almost 71 percent of survey respondents indicated that the
U.S. is rapidly running out of fossil fuels, yet the U.S.
is home to significant reserves of fossil fuels. Putting aside
the issue of whether domestic energy resources are currently
available for extraction—and not counting the abundant
natural resources available to the U.S. in the global marketplace—the
Energy Information Administration’s most recent statistics
reveal that, as of the end of 2007, the U.S. possessed more
than 21.3 billion barrels of proved oil reserves,[17]
more than 237.7 trillion cubic feet of dry natural gas, and
more than 9.1 billion barrels of natural gas liquids.[18]
Even more abundant than our oil and natural gas reserves is
our stock of coal. As of January 1, 2008, our demonstrated
reserve base (DRB)[19] contained 489
billion short tons of coal. However, because of property-rights
issues, land-use conflicts, and physical and environmental
restrictions, the EIA estimates that only half of the DRB
may be available or accessible for mining (262 billion short
tons, as of January 1, 2008).[20]
Finally, though not a fossil fuel, uranium—the primary
fuel used to produce nuclear energy—is abundant in the
United States. As of December 31, 2003,[21]
given forward costs of $30, $50, and $100 per pound, U.S.
uranium reserves totaled 265 million pounds, 890 million pounds,
and 1,414 million pounds, respectively.[22]
Should renewables not advance as rapidly as many expect or
hope, the nation’s fossil-fuel and uranium reserves should
alleviate some concern about our overall electricity and fuel
supply.
Given our abundance of fossil fuels and uranium, their dominance in our nation’s
electricity supply—they collectively accounted for just over 91 percent
of U.S. electricity generation in 2007—is not surprising. The EIA projects
that these fuels will still account for 85 percent of our total electric generation
in 2030.[23] Moreover, though petroleum generated only
1.6 percent of our electricity in 2007,[24] it accounted
for 96 percent of our nation’s transportation fuel.[25]
For many, however, the amount of such reserves and their collective contribution
to our energy supply have no bearing on whether, or how quickly, we should transition
to renewable sources of energy. Shouldn’t we be moving toward renewables
anyway, in order to become energy independent? Ironically, because renewables
are not commercially viable technologies, the goal of energy independence is
at odds with reducing our use of conventional fuels. Unless we are willing to
cut our energy use drastically, cutting back on imported fuel means that our
consumption of domestic fossil fuels and uranium must increase. Moreover,
even if everyone agreed that we should replace such fuels with renewables, significant
economic and technological barriers stand in the way of a quick and easy transition.
Almost half (49.4 percent) of respondents believed that renewable sources of
energy—hydroelectric, geothermal, wind, solar, and biomass—are on
track to replace fossil fuels in the near future. While the possibility of a
rapid increase in the contribution of renewables cannot be ruled out entirely,
current growth trends do not put us on a track to replace fossil fuels anytime
soon.
Renewable energy sources met about 7 percent of our total energy needs in 2007.
Of this 7 percent, biomass energy contributed 53 percent, hydroelectric energy
contributed 36 percent, wind energy and geothermal energy contributed 5 percent
each, and solar energy contributed 1 percent.[26] Renewable
energies accounted for 8.3 percent of the nation’s electricity generation
in 2007,[27] down from 9 percent in 2003[28]—though
the EIA projects the share to increase in the years ahead. The largest share
of renewable-generated electricity in 2007 came from hydroelectric energy (71
percent), followed by biomass (16 percent), wind (9 percent), geothermal (4
percent), and solar (0.2 percent).[29]
Given renewable energies’ current costs and technological limitations,
as well as the limitations of an electricity grid and fuel-pipeline system designed
for traditional power sources and fuels, renewables are not expected to be major
players in our fuel-supply mix in the near term. The EIA projects that renewables—including
hydroelectric power—will account for 14 percent of total U.S. electricity
generation in 2030.[30] (Wind energy generated 0.77
percent of U.S. electricity in 2007[31] and is projected
to generate 2.5 percent of U.S. electricity in 2030.)[32]
This translates to an average annual growth rate of 3.2 percent, the largest
increase of any fuel type.[33] The EIA says that this
growth will be “fueled by the rapid expansion of non-hydro renewable generation
technologies that qualify to meet State mandates for renewable energy production.”[34]
An oft-repeated refrain is that renewable energies, in addition to being cleaner,
are cheaper than their conventional fuel counterparts. Thus, it is not surprising
that a majority (53.7 percent) of respondents indicated that it is cheaper to
generate electricity from renewable fuels like wind or the sun than it is to
produce electricity from fossil fuels, like coal or natural gas. However, there
is a difference between the cost of renewable fuels and the cost of producing
energy from such fuels.
Though wind and solar rays are indeed free, wind energy and solar energy are
costly, compared with the costs of conventional power generation. Several factors
make renewables more expensive, including high costs of materials and skilled
labor, added operations costs to electric grids that were not built for intermittent
resources, and lack of adequate transmission lines to carry power from remote
areas (where the wind and the sun are most plentiful) to densely populated demand
centers. In addition, large federal subsidies and state renewable energy mandates
shift many costs of renewable energy production from generators to electric
ratepayers, disguising the true costs of these technologies.
In
addition, subsidies for wind and solar energy—which together
generated less than 1 percent of our nation’s electricity
supply in 2007—are significantly more generous than subsidies
for conventional power generation, considering the amount
of electricity generated by each source.[35]
In 2007, wind energy received $724 million in federal subsidies,
valued at $23.37 per megawatt hour (MWh) of wind-generated
electricity, while solar energy took in $174 million, at a
subsidy-per-MWh value of $24.34. By contrast, coal received
a subsidy of 44 cents per MWh, natural gas and petroleum liquids
received 25 cents each, hydroelectric energy took in 67 cents,
and nuclear power grabbed $1.59.[36]
Without these generous taxpayer-funded subsidies, renewable
energies would not be competitive with conventional energy
sources.
Like renewable energies, hybrid cars and alternative-fuel vehicles (AFVs),
including electric cars, have become more prominent in fuel-policy discussions,
and they are more prevalent on U.S. roads than ever.[37]
Almost two-thirds (62.7 percent) of respondents believed that such vehicles
will constitute a large portion of all U.S. automobiles in ten years—but
again, projections are less optimistic.
From 2003 to 2006, AFV use increased by an annual average of just over 6.27
percent[38]—but, with 250,851,833 registered vehicles
in the U.S. in 2006,[39] AFVs made up just one-quarter
of 1 percent of all registered vehicles in 2006. And, according to J. D. Power
& Associates, sales of hybrid cars—which run on either gasoline or
diesel and electricity generated onboard—will account for just 7 percent
of the car market in 2015, up from 2.2 percent in 2007.[40]
As our energy economy increasingly relies on electricity, it is important to
assess whether electric cars and plug-in electric hybrids (PHEVs), which are
powered completely and partially, respectively, by batteries charged by electric
grids, are ultimately more environmentally friendly than hybrid cars or even
vehicles that run on conventional fuels. Opinions vary. “Odds are those
batteries won’t be recharged with solar or wind energy,” writes John
Voelcker in Spectrum, the flagship publication of IEEE, formerly known
as the Institute of Electrical and Electronics Engineers, Inc.[41]
“In most places, grid power is for many decades going to come from the
burning of fossil fuels, which generate their own emissions.”[42]
In other words, if coal plants supply the electric grid with the bulk of the
power needed to charge electric cars, will overall greenhouse-gas (GHG) emissions
increase? Voelcker writes, “The moral of the story: If you’re concerned
about the carbon footprint of your vehicle travel, definitely buy a plug-in—if
you live in Norway, Brazil, France, or other areas with largely carbon-free
electricity. Otherwise, have a look at your local grid—and think twice
if you live in a place with lots of old coal-fired power plants. For you, a
conventional hybrid may be kinder to the planet.”[43]
On the other hand, many studies reveal that replacing conventional vehicles
and hybrids with electric cars and PHEVs will lead to an overall reduction in
GHG emissions. The American Council for an Energy-Efficient Economy writes that
PHEVs “will reduce both their fuel consumption and their emissions of various
pollutants relative to current vehicles, including non-plug-in hybrid-electric
vehicles” and that “the advantage of plug-ins over hybrids is large
in areas where electricity is generated with low-carbon fuels, and much more
modest elsewhere.”[44] Using three scenarios for
the level of PHEV market penetration and three scenarios for electric-sector
carbon-dioxide intensity, the Electric Power Research Institute and the National
Resource Defense Council produced nine possible outcomes for PHEVs’ effects
on overall GHG emissions. Their study concluded that annual and cumulative GHG
emissions would decline significantly under each outcome and that each region
of the country would see reductions in GHG emissions.[45]
As politicians and policymakers continue to worry about climate change, foreign
oil dependence, and the availability of domestic energy resources, renewable
energies and alternative fuels will potentially play larger roles in meeting
our country’s energy needs. However, because of the high costs of renewable
energies and alternative transportation fuels relative to their conventional
counterparts and because of technological limitations and transmission-infrastructure
inadequacies, conventional power sources and transportation fuels will remain
the dominant suppliers of our nation’s energy for years to come.
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