Earlier, CNAV treated the environmental soundness of electric vehicles. A German study released this week showed battery-powered electric vehicles are not
nearly as environmentally sound as people imagine. In fact the study
authors assert that even a Diesel vehicle does the environment less
harm than an electric vehicle. That sounds totally counterintuitive,
but has sound science behind it. The best way to see why electric vehicles will not save the planet—yet–is to understand
their worst failing. That failing is efficiency, from the first fuel
source to the wheels that give a vehicle its name.
How
to measure efficiency
Energy
efficiency, according to this article in Wikipedia, is the ratio of work done to energy put in. Energy,
from the Greek en- within and ergon a
work, is the ability to do work.
In this case, moving a vehicle down a road takes work.
The Otto engine, that most
conventional vehicles use, is least efficient at about 35
percent, best-case. Diesel engines fare better, at about 45 percent.
The steam turbine that runs your local
power plant is slightly less efficient than a Diesel engine. It
scores about 42 percent, give or take one. On this figure depends
every calculation about the efficiency of a power plant that burns
its fuel. With one exception: natural gas power plants, using a
combined steam and gas turbine cycle, can score 60 percent efficient.
Bright Hub Engineering rates the efficiency of different electric power plants. They also score
natural gas at 60 percent efficient. Coal-fired plants score 48
percent, best-case.
A word about nuclear power
Nuclear power plants are the
least efficient of all. Their thermal efficiency is
38 percent, but their overall efficiency is lower still, at
0.27 percent. But the tremendous amount of energy from nuclear
fission makes them viable, and their power cheap. That very low
efficiency figure suggests much room for improvement. That
improvement would lie in
capturing more energy from fission to put into the steam turbine.
Two
different kinds of solar plants
One can capture energy from the
sun (on the ground) in one of two ways. Simply boiling water for a
steam turbine yields an efficiency of 20 percent, even in summer.
Photovoltaic cells do almost
twice as well. Wikipedia cites efficiencies from a low of about 33 percent up to 46 percent for the
best modern designs.
This
Earth receives an average daily dose of the Sun’s rays amounting to about
1000
watts per square meter. A
solar boiler could achieve 200 watts per square meter of the mirrors
required. Photovoltaic cells might generate as many as 300 watts per
square meter, or more. Bear this in mind when trying to replace
non-renewables by renewables—completely.
Other renewable sources
A hydroelectric dam can boast 80
or 90 percent efficiency, if one has a nearby river. One must also remember that one can put only
so many dams in a river. Put in one too many, and the river slows to
a trickle and helps no one.
A wind turbine scores at 30 to 45
percent. That depends on how strongly the wind blows and how quickly
it can turn to face a gust. Gusts never blow in the prevailing direction.
Solar and wind energy
are intermittent. To solve that problem, one must use a battery,
either at the power plant or anywhere else in the grid. This
article describes techniques for “grid energy storage” in
use or development.
Efficiency of electric vehicles
Too many policymakers have
decided to measure efficiency of
electric vehicles in the
vehicle itself. Electric vehicles, according
to this report,
can score 73 percent efficient using battery power. (Fuel-cell
vehicles score surprisingly low, at 22 percent.) But this report
measures the efficiency of the power from grid to wheels.
Almost ten years ago (in fact,
two days before the Climategate story broke),
Tom and Cathy Saxton scored electric vehicles at 80 percent efficient. Again, they measured
efficiency in the vehicle,
not for making the energy to put in.
The Saxtons also cited references
that are no longer available. Happily, the Wayback Machine can bring
them both back. Why the
sources took those down, one can only speculate.
Can the grid stand the strain?
First is the “Wellinghoff
Report” on whether enough electric power existed to run millions
more electric vehicles. This report looked at plug-in hybrids, not
the all-electric vehicles of today. The
Report calculated that the grid could support a 73 percent
replacement of “light duty vehicles” by plug-in hybrids. Light
duty here means “cars, pickup
trucks, SUVs and vans.” Those figures hold for plug-in hybrids.
All-electric vehicles need much more power, because they use no other fuel.
So even nine and a half years
ago, the government never thought the grid could support replacing every car, etc. even
with a plug-in hybrid. It could support an even lower replacement by battery-powered electric vehicles. That assumes no one
builds any more power plants, nor shuts any existing plants down. But
the Green
New Deal calls for replacing coal, natural gas, oil,
and nuclear energy with
renewables only.
Tesla’s calculations of “well-to-wheels”
efficiency for electric vehicles
Second is the efficiency
calculations page Tesla maintained at the time. Tellingly, Tesla does not
maintain this page anymore. The
direct link redirects to a page advertising Tesla’s charging
options for the electric vehicles it makes. But the Wayback Machine
shows us what Tesla was saying nine and a half years ago.
For electric vehicles, Tesla went
to the “well” of natural gas. Natural gas carries most of the
“peak load” for electricity; coal carries the rest. (Nuclear
power carries the base load.) Tesla quoted 52.5 percent
“well-to-station” efficiency, which agrees with 60 percent
efficiency of natural gas power plants. Then
they failed to “show their work” for calculating “vehicle
mileage” and “vehicle efficiency.” So for what it’s worth,
they boasted that their electric vehicles were twice as efficient as
the best hybrids, three times as efficient as a hydrogen fuel cell
vehicle, and seven times as efficient as a “muscle car” (like the
Chevrolet Corvette®).
Conclusion:
we don’t know
Even when Tesla kept up a
calculations page, they didn’t “show their work.” So we cannot
know how efficient electric vehicles truly are. Recall that German study showing
that electric vehicles cause more “emissions” than they spare.
Their manufacture causes the greatest amount of emissions. Driving
them provokes more, in a country that gets its energy from coal.
More to the point: electric
vehicles are the means for using “renewables” to power
transportation. That applies to ground transportation only. (Recall
also that the GND proposes totally obviating air transport, with no distinction between overland and overseas
flights!)
Complete renewable replacement
The site Statista.com shows the total energy budget of American civilization, by source. If
electric vehicles score 73 percent efficient after charging, then
perhaps one-half of the total energy contribution from crude oil would suffice. That
comes to 18
quadrillion BTU, or 18 quintillion Joules,
per year. (1 BTU comes to a thousand Joules, in reasonably round
figures.) This takes into
account the use of petroleum in industry and aviation. Electric
motors can replace piston engines but not jet engines. Forget
trying to do without air travel. Instead,
someone will need to develop a jet engine that uses hydrogen instead
of kerosene.
That still leaves natural gas and
coal to replace totally.
Total budget: 41 quadrillion BTU, or 41 quintillion Joules. Add
nuclear power, because the Triumfeminae1 of the House want to replace that too. That’s another 8.5
quintillion Joules.
And the numbers come to…
So the replacement cost comes to
68 quintillion Joules per year. That’s one year, of 365.24 days,
each having 24 hours of 3600 seconds each, or roughly 31.6 million
seconds. Dividing 68 quintillion by 31.6 million, we arrive at 2.2 terawatts.
Strata.org studied the land footprints of various ways of making electric power. As one
might expect, coal, natural
gas, and nuclear power need 12 acres—0.049
square kilometer—per megawatt. Solar needs 0.20 square kilometer,
wind 0.29, and hydro 1.27. The
figure for the solar plant footprint assumes re-roofing single-family
homes, office buildings, stores, factory hangars, and the like with
new solar “shingles” or strap-on panels. Otherwise the required
initial footprint would be nearly twice as broad.
The
land footprint
So to
make up 2.2 terawatts requires 440,000
square kilometers, or 440 billion square meters.
To be fair, subtract the
existing coal, natural gas, and nuclear footprints: 108,000 square
kilometers. That leaves 332,000 square kilometers extra to get it done. (And if you add more wind or hydro into the mix, the
footprint gets larger.)
The total land area of the USA is about 9.1 million square kilometers, or 9.1 trillion square meters. But
that includes settled land, Native American reservations, rivers, and
lakes. And in what remains,
someone must find land equal to 3.7 percent of all the land in the
United States.
Where
are you going to find the land?
OK, ye Triumfeminae of the House! Where are you going to find all that
land? Talk fast! You gave
yourselves and the country ten years!
Or did you in fact plan to
confiscate all “light-duty vehicles” except for police and
military vehicles and official limousines? And
maybe jam everyone into some of Paolo Soleri’s Arcologies and get the extra land that way? To
paraphrase a popular scandal rag, inquiring minds want to know.
Inquiring minds also want to
know why civilization should stagnate, as it must under this regime.
One final word: the accident hazard
Remember, too, one last hazard of
electric vehicles. “One false move, and ZAP!” So said an
automobile mechanic working on plug-in hybrid models. The batteries
in all-electric vehicles are even more dangerous, not only to
mechanics but also to emergency first responders.
About the image
These wind turbines stand somewhere along the road from Hamburg to Berlin, in Germany. Wind power has an even larger footprint-per-unit-power than does ground-based solar power.
“Wind Turbines” by Tony Webster is licensed under CC BY 2.0. To view a copy of this license, visit: https://creativecommons.org/licenses/by/2.0.
1 A triumfemina or triumfem is the female counterpart to a triumvir.
The Triumfeminate of the House includes Reps.
Alexandria Ocasio-Cortez (D-N.Y.),
Rashida Tlaib (D-Mich.),
and Ilhan Omar (D-Minn).
They back each other up in
everything each of them says or drops into the hopper. Caesar,
Pompey, and Crassus did one another such favors in ancient Rome. And
through sheer intimidation and virtue-signal desire, these three
women, and not Rep.
Nancy Pelosi (D-Calif.), Speaker of the House, lead the House.
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