Ecosicence: Debunking the Hazards of Alternative Energy Sources

Inhaber offers no estimate of the disease effects of the
oxides of nitrogen, hydrocarbons, or trace minerals
(mercury, lead, cadmium, nickel, etc.) that are emitted
when fossil fuels are burned; entirely neglects to
mention public disease caused by water pollution from
contamination by the hydrocarbons and the trace metals that
are released during extraction, processing, and
transportation of fossil fuels; and he ignores all of
the diseases and genetic effects that may appear in future
generations as a result of nuclear-power-produced radiation
or chemical mutagens from fossil fuels.

Admittedly, the data needed to make meaningful estimates of
some such effects are simply not available. That’s all the
more reason to find fault with the repeated assertions by
Inhaber–and especially by the AECB–that his
analysis is a comprehensive treatment of the accident and
disease risks of energy sources. Such
statements, in turn, attempt to justify the report’s
sweeping conclusions about which power sources are more
dangerous than which others.

A Consistent Comparison?

Actually, most of Inhaber’s analysis of public health and
occupational health consequences consists of multiplying
tonnages of materials (say, the amount of steel needed to
build a windmill) by the man-hours–in various
occupational categories — needed to make the
material, fabricate it into the needed components, and
construct a finished energy facility from these parts.
Next, Inhaber multiplies the man-hours in the various
occupational categories by the corresponding rates of
incidence of occupational risk. And if the air pollution
produced per ton of material and the ton-miles of
transportation are known, he adds in estimates of the
public health consequences of these two processes as well.

So far, so good? The catch is that, while Inhaber has
indeed applied this method to his analysis of the
nonconventional energy sources and of hydropower–and
while his report and various published summaries lead the
casual reader to believe he used the same approach for
coal, nuclear power, oil, and natural gas–he, in fact, has
not counted the risks of creating these conventional
facilities at all, only the risks of operating and
maintaining them!

Inhaber made a number of less obvious blunders, too. His
data on conventional energy technologies relate to real
commercial systems, in which economic forces have acted to
minimize the amounts of materials and labor used. But the
same estimates for nonconventional energy technologies, on
the other hand, are for preliminary commercial designs, for
experimental systems, or for entirely hypothetical
installations in which there has been little or no
economic optimization. Moreover, from the array of data
available, Inhaber has almost invariably chosen examples
that are most demanding of materials and labor–and many
of these designs will probably never be built commercially,
since they’ll be beaten out in the marketplace by the more
frugal designs that the study chooses to ignore (or by
still more thrifty ones not yet invented).

Conceptual Confusions and Misreadings 

One of the study’s most elementary errors is the assumption
that one Btu (or joule or kilocalorie) is the same as any
other (Heat is taken as the equivalent of electricity,
electricity at the power plant is considered to be
equivalent to mechanical energy delivered to the wheels of
an automobile … and so on.) This error alone is
responsible for inflating Inhaher’s estimate of the risks
of methanol production by a factor of between three and
six!

However, Inhaber’s most important conceptual confusion is
his complete misunderstanding of the storage and backup
requirements of intermittent energy sources such as
sunlight and wind.

He provides his solar power plant with enough energy
storage to match or exceed the annual energy output of a
coal-fired or nuclear-powered plant with the same rated
capacity. Because of this particular solar plant’s very
large built-in energy storage (the materials and labor
requirements for which Inhaber cheerfully tallies up), the
installation is more than a match for the conventional
baseload plant it replaces. Yet Inhaber irrationally
charges the solar plant with an additional megawatt-year of
coal “backup” for every  megawatt-years of
solar-generated electricity it produces. Such unnecessary
backup systems account for 65-85% of his upper limit risk
estimates for wind, photovoltaic, and solar-thermal-electric
technologies.

Other conceptual errors in AECB-1119 include: adding
together occupational and public risks (which should not be
combined because–among other reasons–the public
risks are largely involuntary, while the bearers of
occupational risks often have made a conscious choice to
accept the hazards in exchange for the wages and other
benefits of their jobs); ascribing the same number of
“days lost” to premature death from aggravated respiratory
disease as to death from cancer (which is incorrect because
the former disease usually takes weeks or months off its
victims’ lives, while the latter–on the
average–cuts a lifespan by many years); and
inflating the risks of coal as compared to nuclear power by
assuming mining conditions and pollution control practices
that are out of date and now illegal.

Inhaber’s 50-fold misreading of a windplant’s material
requirements was discussed in our previous column. In
connection with ocean thermal energy conversion (OTEC), he
understates–by more than twice –the generating
capacity of the unit whose material requirements he
tabulates, while overstating the construction labor
requirements by 10 to 50 times!

The report’s author also claims to have used the highest
available nuclear accident risk values, in order not to be
accused of pronuclear bias. Actually, Inhaber’s “upper
limit” estimate of nuclear accident risk is from two to
several hundred times lower than those given in three of
the four references on reactor safety he cites. He also
implies that he has included estimates of the risk of
radioactive-waste management. He hasn’t.

Irrational Calculations

Inhaber’s assessment of the risks involved in constructing
a methanol factory are scaled from figures for an oil
refinery, and are for operation and maintenance, rather
than for construction. His material and labor requirements
for obtaining natural gas (figures that he never actually
translates into risks, as noted above) come from data for
fuel-oil and coal-gasification facilities.

To obtain material requirements for energy storage at a
solar-thermal-electric plant, he subtracts the weight of a
hypothetical plant with no storage from the weight (as
given in a later report from the same project) of a similar
plant that includes storage. Since the difference in the
quoted weights was caused by the correction of earlier
errors and changes in assumptions–as well as by the
addition of a storage unit– the procedure is useless.
Yet, this same storage system size was then used for
Inhaber’s calculations for photovoltaic and windpower
plants as well even though, as a heat storage system,
it’s completely irrelevant to those technologies.

Because the study considers energy sources in Canada,
Inhaber scales up the size of his solar-thermal-electric
power plant by 32% to account for Canada’s having 32%
less sunlight than the southwestern U.S., the area for
which the plant was designed. In reality, only the size of
the collector needs to be increased to enable such a plant
to produce the same amount of energy as it could in
America’s Southwest, but Inhaber has increased the size
of the boiler, the generator, and even the coal backup
system by the same factor.

He inflates the material requirements for the production of
photovoltaic cells by a bizarre procedure that depends on
rejecting a number that’s easily seen to be correct and
cobbling up a “correction” factor which is based, in
part, on a misunderstanding of the difference between the
peak and average output of solar cells.

Then, to build up his estimate of risk per unit of energy,
Inhaber combines some of the highest figures for the
material requirements of renewable energy systems with some
of the lowest system performance figures available. His
risk estimates are inflated still further by the false
assumption that people in the most dangerous occupations
(e.g., roofing and sheet metal) perform most of the work on
renewable energy installations.

In a similar scam, Inhaber uses material requirements for
an unconventional power plant from a respectable reference,
but ignores that reference’s figure for the plant’s annual
output in favor of lower figures found elsewhere. In one
example, he takes his material requirements–for
windplants–from the Project Independence report, but
ignores that study’s annual load factor of 0.34 (34
megawatt-years of annual output for each 100 megawatts of
rated capacity) in favor of the figure of 0.06. (This lower
load factor has the effect, of course, of increasing the
materials needed per megawatt-year of output.)

Unsubstantiated Assumptions

The study also makes the unwarranted assumption that
facilities producing methanol from biomass will wear out in
20 years, while oil refineries will last three decades This
sort of faulty figuring inflates the construction risk of
biomass by 50%. Inhaber also assumes that such a plant will
be twice as big as an oil refinery per unit of energy
output, ostensibly because methanol contains about half
as much energy per pound as does gasoline. This twofold
increase in methanol’s construction risk is unwarranted,
for methanol’s simpler technology probably would result in
a plant that’s smaller per unit of energy output than is a
complex gasoline refinery.

Inhaber also assumes that all the materials used to
construct unconventional energy facilities–including
rock for energy storage and sand and gravel to make
concrete–must be hauled 300 miles, the average
transport range for coal used in power production. This
assumption leads to a large risk associated with
transportation accidents, when–in reality–such
common materials must travel only a few dozen miles.

To estimate the maintenance risk of rooftop solar heating
systems, Inhaber starts with a very generous estimate of
the time he thinks professional roofers would need for the
job, and computes their injury rate for this number of
hours. Then he multiplies this risk by four, assuming
that homeowners who maintain their own collectors will take
twice as long to do the work and will fall off the roof
twice as often per hour!

Covering the Trail

How could such an array of mistakes have escaped the notice
of the reviewers of the articles in which Inhaber
summarized his own “results” for Science, New Scientist,
and Energy? Part of the answer is that none of Inhaber’s
detailed calculations–and few of his
assumptions–were included in the articles he
submitted for publication. The bodies were all buried in
the report’s appendices, and further concealed under layers
of arithmetic mistakes and typographical errors To unravel
the chain of fallacies that led to the conclusions amounted
to a major undertaking even for an expert at risk
assessment like our colleague, John Holdren (whose group is
responsible for the critique reported here).

One of the ironies of the Inhaber fiasco is that Science
magazine, whose February 1979 article by Inhaber gave his
conclusions their widest circulation, had
published only eight months earlier an editorial
entitled “Bad Science and Social Penalties” by Cyril Comar
(a nuclear advocate from the Electric Power Research
Institute), which contains a description of “bad science”
that fits AECB-1119 like a glove. Comar was also remarkably
prescient in predicting the kind of public response
Inhaber’s work has received: “Bad science, being more
newsworthy, will tend to be publicized and seized on by
some to support their convictions.”

We are in complete agreement with Comar’s prescription for
dealing with the general problem: “Perhaps the best
solution lies in greatly increased efforts of individual
scientists … to vigorously take the initiative and
responsibility, to immediately expose bad science whenever
it occurs, and thereby to reestablish credibility.

Paul Ehrlich (Bing Professor of Population Studies and Professor of Biological Sciences, Stanford University) and Anne Ehrlich (Senior Research Associate, Department of Biological Sciences, Stanford) are familiar names to ecologists and environmentalists everywhere. As well they should be. Because it was Paul and Anne who–through their writing and research–gave special meaning to the words “population,” “resources,” and “environment” in the late 1960’s. (They also coined the term coevolution, and did a lot to make ecology the household word it is today.) But while most folks are aware of the Ehrlichs’ popular writing in the areas of ecology and overpopulation (most of us–for instance–have read Paul’s book The Population Bomb), far too few people have any idea of how deeply the Ehrlichs are involved in ecological research (research of the type that tends to be published only in technical journals and college textbooks). That’s why it pleases us to be able to present these semi-technical columns by authors/ecologists/educators Anne and Paul Ehrlich.