You are engaging in the typical obsfucation that is the trademark of nuclear power's supporters.
YOU are the one claiming the 60% figure and you've yet to support it. First I asked you do define it. You have even now (two posts later) not explained exactly what you mean by "baseline" as opposed to "baseload" and
why the discussion in the OP paper is flawed.
Your unsupported opinion and a meaningless graph isn't enough.
The “baseload” myth
Brand rejects the most important and successful renewable sources of electricity for one key
reason stated on p. 80 and p. 101. On p. 80, he quotes novelist and author Gwyneth Cravens’s
definition of “baseload” power as “the minimum amount of proven, consistent, around-the-clock,
rain-or-shine power that utilities must supply to meet the demands of their millions of
customers.”21 (Thus it describes a pattern of aggregated22 customer demand.) Two sentences
later, he asserts: “So far comes from only three sources: fossil fuels, hydro, and
nuclear.” Two paragraphs later, he explains this dramatic leap from a description of demand to a
restriction of supply: “Wind and solar, desirable as they are, aren’t part of baseload because they
are intermittent—productive only when the wind blows or the sun shines. If some sort of massive
energy storage is devised, then they can participate in baseload; without it, they remain
supplemental, usually to gas-fired plants.”
That widely heard claim is fallacious. The manifest need for some amount of steady, reliable
power23 is met by generating plants collectively, not individually. That is, reliability is a statistic-
al attribute of all the plants on the grid combined.24 If steady 24/7 operation or operation at any
desired moment were instead a required capability of each individual power plant, then the grid
couldn’t meet modern needs, because no kind of power plant is perfectly reliable. For example,
in the U.S. during 2003–07, coal capacity was shut down an average of 12.3% of the time (4.2%
without warning); nuclear, 10.6% (2.5%); gas-fired, 11.8% (2.8%).25 Worldwide through 2008,
nuclear units were unexpectedly unable to produce 6.4% of their energy output.26 This inherent
intermittency of nuclear and fossil-fueled power plants requires many different plants to back
each other up through the grid. This has been utility operators’ strategy for reliable supply
throughout the industry’s history. Every utility operator knows that power plants provide energy
to the grid, which serves load. The simplistic mental model of one plant serving one load is valid
only on a very small desert island. The standard remedy for failed plants is other interconnected
plants that are working—not “some sort of massive energy storage devised.”
Modern solar and wind power are more technically reliable than coal and nuclear plants; their
technical failure rates are typically around 1–2%. However, they are also variable resources
because their output depends on local weather, forecastable days in advance with fair accuracy
and an hour ahead with impressive precision.27 But their inherent variability can be managed by
proper resource choice, siting, and operation.28 Weather affects different renewable resources
differently; for example, storms are good for small hydro and often for windpower, while flat
calm weather is bad for them but good for solar power. Weather is also different in different
places: across a few hundred miles, windpower is scarcely correlated, so weather risks can be
diversified. A Stanford study found that properly interconnecting at least ten windfarms can
enable an average of one-third of their output to provide firm baseload power.29 Similarly, within
each of the three power pools from Texas to the Canadian border, combining uncorrelated
windfarm sites can reduce required wind capacity by more than half for the same firm output,
thereby yielding fewer needed turbines, far fewer zero-output hours, and easier integration.30
A broader assessment of reliability tends not to favor nuclear power. Of all 132 U.S. nuclear
plants built—just over half of the 253 originally ordered—21% were permanently and
prematurely closed due to reliability or cost problems. Another 27% have completely failed for a
year or more at least once. The surviving U.S. nuclear plants have lately averaged ~90% of their
full-load full-time potential—a major improvement31 for which the industry deserves much
credit—but they are still not fully dependable. Even reliably-running nuclear plants must shut
down, on average, for ~39 days every ~17 months for refueling and maintenance. Unexpected
failures occur too, shutting down upwards of a billion watts in milliseconds, often for weeks to
months. Solar cells and windpower don’t fail so ungracefully.
Power plants can fail for reasons other than mechanical breakdown, and those reasons can affect
many plants at once. As France and Japan have learned to their cost, heavily nuclear-dependent
regions are particularly at risk because drought, earthquake, a serious safety problem, or a
terrorist incident could close many plants simultaneously. And nuclear power plants have a
unique further disadvantage: for neutron-physics reasons, they can’t quickly restart after an
emergency shutdown, such as occurs automatically in a grid power failure. During the August
2003 Northeast blackout, nine perfectly operating U.S. nuclear units had to shut down. Twelve
days of painfully slow restart later, their average capacity loss had exceeded 50%. For the first
three days, just when they were most needed, their output was less than 3% of normal.32
To cope with nuclear or fossil-fueled plants’ large-scale intermittency, utilities must install a
~15–20% “reserve margin” of extra capacity, some of which must be continuously fueled,
spinning ready for instant use. This is as much a cost of “firming and integration” as is the
corresponding cost for firming and integrating windpower or photovoltaic power so it’s
dispatchable at any time.33 Such costs should be properly counted and compared for all
generating resources. Such a comparison generally favors a diversified portfolio of many small
units that fail at different times, for different reasons, and probably only a few at a time: diversity
provides reliability even if individual units are not so dependable.
Reliability as experienced by the customer is what really matters, and here the advantage tilts
decisively towards decentralized solutions, because ~98–99% of U.S. power failures originate in
the grid. It’s therefore more reliable to bypass the grid by shifting to efficiently used, diverse,
dispersed resources sited at or near the customer. This logic favors onsite photovoltaics, onsite
cogeneration, and local renewables over, say, remote windfarms or thermal power plants, if
complemented by efficient use, optional demand response, and an appropriate combination of
local diversification and (if needed) local storage, although naturally the details are site-specific.
The big transmission lines that remote power sources rely upon to deliver their output to
customers are also vulnerable to lightning, ice storms, rifle bullets, cyberattacks, and other
interruptions. These vulnerabilities are so serious that the U.S. Defense Science Board has
recommended that the Pentagon stop relying on grid power altogether.34 The bigger our power
plants and power lines get, the more frequent and widespread regional blackouts will become. In
general, nuclear and fossil-fueled power plants require transmission hauls at least as long as is
typical of new windfarms, while solar potential is rather evenly distributed across the country.
For all these reasons, a diverse portfolio of distributed and especially renewable resources can
make power supplies more reliable and resilient. Of course the weather-caused variability of
windpower and photovoltaics must be managed, but this is done routinely at very modest cost.
Thirteen recent U.S. utility studies show that “firming” variable renewables, even up to 31% of
total generation, generally raises windpower’s costs by less than a half-cent per kWh, or a few
percent.35 Without exception, ~200 international studies have found the same thing.36 Indeed, the
latest analyses are suggesting that a well-diversified and well-forecasted mix of variable
renewables, integrated with dispatchable renewables and with existing supply- and demand-side
grid resources, will probably need less storage or backup than has already been installed to cope
with the intermittence of large thermal power stations. Utilities need only apply the same
techniques they already use to manage plant or powerline outages and variations in demand—but
variations in renewable power output are more predictable than those normal fluctuations, which
often renewables’ variations don’t augment but cancel. Thus, as the U.S. Department Energy
pithily summarizes, “When wind is added to a utility system, no new backup is required to
maintain system reliability.”37
This is not just a computational finding but a practical reality. In 2008, five German states got
30–40% of their annual electricity from windpower—over 100% at windy times—and so do
parts of Spain and Denmark, without reliability problems. Denmark is 20% windpowered today
and aims for ~50–60% (the rest to come from low- or no-carbon cogeneration). Ireland, with an
isolated small grid (~6.5 billion watts), plans to get 40% of its electricity from renewables,
chiefly wind, by 2020 and 100% by 2035. Three 2009 studies found 29–40% British windpower
practical.38 The Danish utility Dong plans in the next generation to switch from ~15%
renewables (mainly wind) and ~85% fossil fuel (mainly coal) to the reverse. A German/Danish
analysis found that diversifying supplies and linking grids across Europe and North Africa could
yield 100% renewable electricity (70% windpowered) at or below today’s costs.39 Similar all-
renewable scenarios are emerging for the United States and the world, even without efficiency.40
Brand nonetheless concludes that “wind power remains limited by intermittency to about 20
percent of capacity (so that 94 gigawatts is
four-fifths illusory), while nuclear plants run at over 90 percent capacity these days; and there is
still is no proven storage technology that would make wind a baseload provider.” That view has
long been known to be unfounded. There is no 20% limit, in theory or in practice, for technical
or reliability or economic reasons, in any grid yet studied.41 The “fourth-fifths illusory” remark
also appears to reflect confusing an imaginary 20% limit on windpower’s share of electrical
output with windpower’s capacity factor (how much of its full-time full-power output it actually
produces). Anyhow, capacity factor averaged 35–37% for 2004–08 U.S. wind projects, is
typically around 30–40% in good sites, and exceeds 50% in the best sites.42 Proven and cost-
effective bulk power storage is also available if needed.43
Even if Brand were right that variability limits windpower’s potential contribution, that would be
irrelevant to windpower’s climate-protecting ability. Grid operators normally44 dispatch power
from the cheapest-to-run plants first (“merit order” or “economic dispatch”). Windpower’s
operating cost is an order of magnitude below coal’s, because there’s no fuel—just minor
operating and maintenance costs. Therefore, whenever the wind blows, wind turbines produce
electricity, and coal (or sometimes gas) plants are correspondingly ramped down, saving carbon
emissions. Coal makes 50% of U.S. electricity, so on Brand’s own assumption of a much smaller
(20%) windpower limit, windpower saves coal and money no matter when the wind blows. To
put it even more simply, physics requires that electricity production and demand exactly balance
at all times, so electricity sent out by a wind turbine must be matched by an equal decrease in
output from another plant—normally the plant with highest operating cost, i.e. fossil-fueled.
Further layers of fallacy underlie Brand’s amiable dismissal of solar power (pp. 101–102):
• For photovoltaics (PVs) to become “a leading source of electricity” does not require
numerous “breakthroughs, sustained over decades”; it requires only the sort of routine
scaling and cost reduction that the similar semiconductor industry has already done. Just
riding down the historic Moore’s-Law-like “experience curve” of higher volume and
lower cost—a safe bet, since a threefold cost reduction across today’s PV value chain is
already in view—makes PVs beat a new coal or nuclear plant within their respective lead
times. That is, if you start building a coal, gas, or nuclear power plant in, say, New
Jersey, and next door you start at the same time to build a solar power plant of equal
annual output, then by the time the thermal plant is finished, the solar plant will be
producing cheaper electricity, will deliver ~2.5× a coal plant’s onpeak output, will have
enjoyed more favorable financing because it started producing revenue in year one, and
will have been made by photovoltaic manufacturing capacity that can then reproduce the
solar plant about every 20 months45—so you’d be sorry if you’d built the thermal plant.
• Photovoltaics’ business case, unlike nuclear’s, needn’t depend on government subsidies
or support. Well-designed photovoltaic retrofits are already cost-effective in many parts
of the United States and of the world, especially when integrated with improved end-use
efficiency and demand response (e.g., PowerLight’s 2002 retrofit of three acres of PVs on
the Santa Rita Jail46) and when financed over the long term like power plants, e.g., under
the Power Purchase Contracts that many vendors now offer. PVs thrive in markets with
little or no central-government subsidy, from Japan (2006–08) to rural Kenya, where
electrifying households are as likely to buy them as to connect to the grid.
• Photovoltaics are highly correlated with peak loads; they often exhibit 60% and
sometimes 90% Effective Load Carrying Capacity (how much of their capacity can be
counted on to help meet peak loads). PV capacity factors can also be considerably higher
than Brand’s assumed 0.14, especially with mounts that track towards the sun: modern
one-axis trackers get ~0.25 in New Jersey or ~0.33–0.35 in sunny parts of California.47
• Solar power, Brand asserts, does not work well at the infrastructure level (i.e., in
substantial installations feeding power to the grid; the largest installations in spring 2009
produced about 40–60 peak megawatts each). This will surprise the California utilities
that recently ordered 850 megawatts of such installations, the firms whose reactor-scale
PV farms are successfully beating California utilities’ posted utility price in 2009
auctions, the firms that are sustaining ~60–70% annual global growth in photovoltaic
manufacturing, and their customers in at least 82 countries. Global installed PV capacity
reached 15.2 GW in 2008, adding 5.95 GW (110% annual growth) of sales and 6.85 GW
of manufacturing (the rest was in the pipeline).48 That’s more added capacity than the
world nuclear industry has added in any year since 1996, and more added annual output
than the world nuclear industry has added in any year since 2004. About 90% of the
world’s PV capacity is grid-tied. Its operators think it works just fine.
The belief that solar and windpower can do little because of their variability is thus exactly
backwards: these resources, properly used, can actually become major or even dominant ways to
displace coal and provide stable, predictable, resilient, constant-price electricity.
Full paper (with notes) available for download here:
http://www.rmi.org/rmi/Library/2009-09_FourNuclearMyths
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