Debate Summary - SPS vs. Wind/Solar/Hydrogen

If you ever find yourself in a debate with an environmentalist on
the best course to insure a secure energy future I offer you this
post as a roadmap of what to expect.

The purpose of this post is to summarize the debate on the merits of
Solar Power Satellites against Terrestrial Solar Power and Wind
Power, and further to also address a comparison between a massive
decentralization of the electrical generating and transmission
systems by use of solar/wind and hydrogen fuel cell technology (as a
means of buffering solar/wind power supply against demand - i.e. a
battery) against SPS power fed into a local transmission grid.

I'll start with some fundamental issues and work my way up to more
complex scientific, engineering, logical and rhetorical topics.

SOLAR POWER

Perhaps an illustrative example can be found by way of a side by
side comparison. Although greater SPS efficiencies (40% +) can be
had by employed a Sterling/Brayton Solar Thermal SPS design, for
sake of simplicity this comparison will employ a SPS Photovoltaic
design against a Terrestrial PV array. The unit of comparison will
be a square meter of PV cells and how much AC electricity each
design can provide to the end-user.

The actual PV composition is immaterial to the comparison for both
the SPS and the terrestrial PV array can be constructed of the same
PV material. This obviates the claims of future breakthroughs making
one technology better than the other.

Thus the comparison boils down to a system analysis. Let's begin.

SOLAR ILLUMINATION

The obvious place to start is to ask how much sunlight each solar PV
cell will receive. For our terrestrial PV cells, this will of course
vary depending on their location on the Earth. Here is some data on
solar illumination.

Hours/Day:
http://www.cetsolar.com/PDF/CET/Avail.pdf
(Minimum - Maximum --> Yearly Average)

Seattle 1.6 - 4.63 --> 3.57
Los Angeles 5.03 - 6.14 --> 5.62
Rochester 1.58 - 4.22 --> 3.31
Chicago 1.47 - 4.08 --> 3.14
New York 3.03 - 4.97 --> 4.08

If we aggregate this to a whole year, we find that there are 1,200 -
2000 hours of sunlight per year across most of the US.

For a Solar Power Satellite in orbit, it will receive 24 hours of
sunlight, 365 days a year, but it will experience yearly eclipses on
the vernal and autumnal equinoxes lasting up to 72 minutes at local
midnight.

So, when comparing solar illumination from terrestrial solar arrays
to SPS, we are comparing about 2,000 hours of illumination to 8,757
hours. That's more than a 4:1 ratio.

SOLAR INTENSITY

OK, so SPS will get more than 4 times the amount of sunlight than
terrestrial solar PV, henceforth called solar PV. What affect will
the intensity of that sunlight have on the electricity that can be
produced?

Well, quite a lot actually.

Many solar activists will have you believe that solar insolation
(the amount of solar energy (watts) that can be collected is 1,000
watts/meter^2 whenever the sun shines. This isn't quite accurate. At
local solar noon, on a cloudless summer day the sun can indeed
produce this insolation. However, as the angle of solar incidence
varies from sunrise to sunset the amount of insolation will also
vary.

Here is an illustration of solar incidence

http://www-astronomy.mps.ohio-
state.edu/~pogge/Ast161/Unit2/insolation.gif

Here is an excellent primer on the duration and intensity of
insolation.

http://www.geog.ouc.bc.ca/physgeog/contents/6i.html

Are the solar activists purposely lying to you? Most likely not.
They honestly believe the figures they quote because they read them
at a solar advocacy site. Or they may be confused by the ratings on
the solar panels. The panels are tested in a chamber where they are
subjected to a 1,000 watt/m^2 flash and measured at how well they
process that flash. If they pass, they are rated for 1,000 w/m^2. So
now we know that they can handle that intensity of sunlight, but how
often do they actually work at top efficiency?

Let's look at some real life data.

The amount of insolation (winter/summer)is:
(kW/h/m^2/day)

Seattle 0.8 - 6.4 --> yearly average 3.7
http://rredc.nrel.gov/solar/pubs/redbook/PDFs/WA.PDF

Los Angeles 3.3 - 7.3 --> yearly average 5.6
http://rredc.nrel.gov/solar/pubs/redbook/PDFs/CA.PDF

Rochester 1.3 - 6.2 --> yearly average 4.1
http://rredc.nrel.gov/solar/pubs/redbook/PDFs/NY.PDF

Chicago 1.8 - 6.6 --> yearly average 4.4
http://rredc.nrel.gov/solar/pubs/redbook/PDFs/IL.PDF

New York 1.9 - 6.2 --> yearly average 4.6
http://rredc.nrel.gov/solar/pubs/redbook/PDFs/NY.PDF

Right away, the Los Angeles data should jump out at you. It has the
least amount of variation between the two insolation extremes, which
usually occur at the winter and summer solstice, when the amount of
daylight is shortest and longest, respectively.

The obvious conclusion to be drawn from these insolation data is
that solar power is most appropriate to regions that are closer to
the equator and have less seasonal variability.

Of course, if you have to live through a Chicago winter you're going
to make sure that the 1.8 kW/h that is produced from each square
meter of solar PV is going to last you during a day's worth of
usage. You're not going to count on receiving the summer insolation
and suffering frostbite and power outages. Thus, you have to design
your solar array for the minimum insolation you can count on
receiving.

Keep in mind that the figure means that a person who uses 1,800
watts for one hour, or 900 watts in two hours, is using 1.8 kW/h.
Every square meter of solar PV will receive that insolation over the
course of a day.

How much insolation will a square meter of SPS receive?

Solar insolation in orbit is about 1,370 watts/m^2, so over a 24
hour day, the SPS will collect 32.88 kW/h, every day of the year,
winter or summer, for every square meter.

Los Angeles in the winter receives 1.8 kW/h and in the summer
receives 7.3 kW/h, compared to the SPS at 32.88 kW/h.

So, for a direct comparison, each using the same PV technology, the
SPS receives 4.5 - 18 times more insolation than a solar PV.

HOW MUCH POWER IS DELIVERED TO THE HOME?

For both the SPS and the solar PV I'm going to use a efficiency
factor of 10%. You can substitute in a higher factor to allow for
innovation in PV technology but it will be available to both SPS and
solar PV.

Let's consider New York City, and use it's winter insolation of 1.9
kW/h/m^2/day. These 1,900 watts/h/m^2/day are in the form of DC
power so to use your appliances that power must be converted to AC.
This process is about 88% - 94% efficient, depending on the scale of
your inverter.
http://www.bitterrootsolar.com/inverter/sunnyboy.htm

So, each square meter will produce 0.1786 kW/h/day in the winter and
0.5828 kW/h/day in the summer.

What can you do with your 0.1786 kW/h/m^2/day? Well, you can turn on
three 60 watt lightbulbs and keep them going all day, for every
square meter of solar PV that is one your roof.

Here is some data on appliance energy use:
http://www.city.ames.ia.us/ElectricWeb/energyguy/appliances.htm

Now let's turn our attention to how well the SPS can do the job. In
this case the process has more intermediate steps because the power
is generated 35,786 km above the surface of the Earth and it has to
make it's way down to your home in a few stages.

There are idiots in the environmental movement who think that this
will be done with power lines and on that basis they try to debunk
SPS.
http://solstice.crest.org/solar/solar_intro.html#solaronthemoon

Fear not dear reader, we will actually be able to get the power to
the surface of the Earth without getting all tangled in power lines.
We'll transmit the power with microwaves.

We start at the same point as the above example, DC power produced
by the SPS PV cells. According to the US Dept of Energy, in their
study "Solar Power Satellite Concept Development and Evaluation
Program - Final Report" once the PV cell has converted the solar
energy to DC power, the next process is to convert that DC power to
Microwave Energy; this is done with an 85% efficiency.

Next that microwave energy has to be beamed towards Earth and there
is a slight loss in the antenna, so the beaming achieves a 98%
efficiency.

The beamed energy is attentuated slightly by the atmosphere, so this
too is only 98% efficient. Compare this 98% to the 22%-70% that
sunlight achieves.

This graph shows attentuation caused by atmosphere and water vapor
against frequency.
http://sina.sharif.ac.ir/~barkeshli/antennas/review/fig21.gif

When the energy is received by the rectenna farm, the Schottky
Barrier Diode Efficiency is 88%.

The microwaves that have now been captured are converted to DC power
at an efficiency of 89%.

Finally, at this point we're at the same point of conversion as the
solar PV that's on your roof. We have to convert the DC power to AC
power via an inverter. Because we're dealing with a utility grade
level of operation, the inverter is slightly more efficient, at 97%.

To sum up all of the loses in the chain, the 100% power we generated
at 10% PV efficiency, the math would look like this:

1.37 kW/m^2 * 24 h = 32.88 kW/h/m^2/day
32.88kW/h/m^2/day * 10% PV efficiency = 3.288 kW/h/m^2/day
3.288 kW/h/m^2/day * 0.85 * 0.98 * 0.98 * 0.88 * 0.89 * 0.97 = 2.039
kW/h/m^2/day

So, even after all of the intermediate steps in transmitting the
power from orbit, the SPS produces 2.039 kW/h for every square meter
of PV cell per day compared to Los Angeles' variable output of
0.1786 kW/h to 0.5828 kW/h.

That's an improvement of 3.5 - 11.4 times better performance. Of
course, the number is really 11.4 for L.A. because you have to
design your solar PV system for the lowest amount of insolation,
which you receive in the winter. For Seattle, with a winter output
of 0.0752 kW/h/m^2/day the multiple is as much as 27.1 times better!

WIND POWER

Wind power has the same limitation as solar PV; it is an
intermittent power supply. The solar PV won't work when the shine
doesn't shine and the wind turbine won't work in no or low wind
conditions.

Residential wind turbine installations suffer from unsightliness and
zoning issues and thus draws more zoning restrictions and protest
than residential solar PV.

Compared to solar PV installation on a household rooftop, a wind
turbine installation requires expensive residential land. Many
homeowners, even if they could get zoning permission to install a
wind turbine might think twice about the land use opportunity cost.

As with solar PV, a wind turbine installation will require battery
back-up to compensate for periods of turbine ineffectiveness.

Moving away from the concept of residential wind turbines and
applying this analysis to wind farms one finds that the low-value
land that has a sufficiently robust wind profile is often far from
where the demand for power is.

Look here for a recap of the many issues that wind farms have to
contend with that won't affect SPS.

Siting issues:
http://www.twincities.com/mld/twincities/2003/09/25/business/6853203.
htm
http://www.sdenergy.org/technology/wind_power.html
http://www.eia.doe.gov/cneaf/solar.renewables/rea_issues/windart.html

Critique of Slipshod Science invoked by Wind Advocates:
http://www.darrylmueller.com/wind.verses.coal.html

Assorted Issues with Wind Power:
http://www.theenergyreview.com/html/1-replace/1-1-2.htm
http://www.cato.org/pubs/pas/pa422.pdf
http://www.numberwatch.co.uk/power_cuts.htm
http://www.xcelenergy.com/XLWEB/CDA/0,2914,1-1-1_5929_3579_5152-4605-
0_0_0-0,00.html

Protest Issues with Wind Power:
http://www.wired.com/wired/archive/10.05/windfarms.html
http://www.windstop.org/pages/2/index.htm
http://www.windstop.org/pages/1/index.htm
http://abcnews.go.com/sections/scitech/DailyNews/wind021029.html

Land use for Solar Energy "Farms"
http://egj.lib.uidaho.edu/egj09/youngqu1.html

ECONOMIC ISSUES OF WIND/SOLAR IN A GRID

When wind or solar farms are added to a transmission system and
utilities are either supplying the power from their own facilities
or buying them from independent suppliers a major issue that has to
be confronted is the intermittancy of the supply.

Electrical demand patterns are fairly regular and have a high degree
of predictability. When a utility has enough generating capacity at
its disposable it is quite easy to match supply to demand and thus
balance the frequency of the electricity to a small range. When
solar/wind is a source of supply what usually happens is that there
is a surge of supply that may suddenly and unexpectedly cease thus
necessitating bringing online a oil/coal/gas or nuclear plant in
order to keep the frequency of the electric power within established
paramaeters. This can cause of a lot of stress to the generating
equipment and often the ramp up time is not as quick as the
disappearance of the wind.

Wind/solar can be competitive when the capital cost of the "farm" is
lower than the fuel cost of the more traditional generating plant.
This is due to the requirement of the coal/oil/gas plant to build up
the generating capacity to accomodate the intermittancy of the
wind/solar infrastructure.

It should be noted that a SPS does not suffer from the intermittancy
problem, nor does it require the baseload backup that is required to
be built to provide insurance against the intermittancy of
wind/solar. SPS has the advantage of being baseload capable just as
the traditional plants and shares with wind/solar the advantage of
being fuelless, thus allowing it to be more capital intensive and
still deliver power at the same cost as the traditinal alternatives.

THE MILLION POINTS OF LIGHT PIPEDREAM

Environmentalists often push for wide spread solar/wind
decentralization so that most households can supply some of their
own power and rely on utility grid backup as only an intermediate
step towards complete decentralization with no grid connection
required.

This philosophic goal lacks a basis for economic rationality. A
typical utility bill that you pay may attribute 30 cents of every
dollar to fuel costs.
http://www.niagaramohawk.com/nimotod/quickfacts/facts.html

The utility must maintain sufficient generating capacity to provide
for demand that is present when solar/wind aren't contributing to
either the household or supplying excess power to the grid.

So, if wide scale decentralization is implemented and homeowners can
achieve a 50% reduction in their power purchases what they'll really
save is only 15% off of their utility bill. Why 15% and not 50%?
Because, the generating plant must still be paid for to supply all
the power that's requested and the utility only saves 50% on its
fuel purchases. Those fuel purchases are typically 30%, so 50% of
30% is 15%, and that's why the homeowner's savings will be so low.

At this point the environmentalists pipe up with their hydrogen fuel
cell storage rejoinder. It usually goes like this "If you install
solar PV on your roof and put a fuel cell in your basement then you
could disconnect from the grid and all of the economic arguments
that are unfavorable to decentralization are refuted."

If only it were so.

For this nirvana to come to pass, each homeowner would have to
install overcapcity in their wind/solar equipment so as to meet
their current power demand and also generate enough electricity to
power their fuel cell during non-generating hours.

What does this mean to a typical homeowner? Well we can't rely on
the usual canard of a 1,000 kW/h per month energy usage. Maybe that
was the case some time ago, but no longer.

http://www.sptimes.com/2003/02/10/Business/The_cost_of_making_th.shtm
l
"When Tampa Bay area utilities raise (or occasionally lower) their
electricity rates, it's customary to say what the result would be
for a "typical residential monthly bill of 1,000 kilowatt hours."

"That may have once been typical, but Kevin Bloom, a spokesman for
the Florida Public Service Commission, says that household energy
consumption often exceeds that level now because of increased use of
home electronics, such as TVs, computers and audio equipment."

"So what's really typical today? The median household customer of
Tampa Electric used 1,356 kilowatt hours, or kwh, a month in 2002."

Well, maybe you're thinking that 1,350 kW/h/ month isn't that bad if
that's all it takes to disconnect from the grid and be self-reliant.

Baby, you ain't even close, for how self-reliant will you be if
you're still connected to a gas pipeline or an oil truck? No, we all
know that environmentalists are the paragons of consistency, so I'm
sure they mean that you're completely disconnected and that means
your 1,350 kW/h a month will have your freezing or sweltering in
your home.

Typical heating energy use based on DOE's 1998 "Representative
Average Unit Costs of Energy" and on a 2,100-square-foot, well
insulated home in a moderately cold temperature region, such as St.
Louis, Mo.
http://www.atmosenergy.com/about/gas/home/heating.html

20,087 kW/h year - electrical resistance heating
8,812 kW/h year - Heat pump requiring back-up heat below 40 degree F.

Let's split the difference and say half the homes are electrical
resistance and the other half efficient heat pumps (with electrical
baseboard backup heat) and we come to a useage of 14,500 kW/h per
year.

So, the monthly energy use for a home really amounts to 2,560 kW/h.
That's a far cry from the 1,000 kW/h.

So let's say you're living in Rochester, NY and you need to insure
that you have sufficient power and heat for your *average* home, how
much solar PV area will you need?

You'll need about 85 kW/h per day. You can count on 0.1222
kW/h/m^2/day generating capacity.

If we assume that the demand can be directly met by the solar PV for
5 hours of the winter day, then the remaining 19 hours must be met
by their reversible fuel cell which operates at 70% efficiency.

This fuel cell will combine hydrogen and oxygen through a platinum
catalyst to form electricity and water and then use electricity to
split the water back into hydrogen and oxygen. Of course I'm
ignoring the issue of the time it takes to split the water back to
hydrogen and oxygen and the gas stroage issue. I don't want he
environmentalist to have a stroke when they're reading this :)

http://www.eere.energy.gov/hydrogenandfuelcells/pdfs/32405b25.pdf
". . .reversible (fuel cell-electrolyzer) systems having round trip
efficiencies of 70% and costs under $600 per kW."

So, 67 kW/h must be supplied by the fuel cell and 18kW/h can be
supplied directly from the solar PV during the 5 hour day.

The 67 kW/h supplied by the fuel cell will require 96 kW/h to power
the reversible electrolytic process.

The 96 kW/h must be collected during the period that the sun is
shining so the solar PV system must be overbuilt in order to collect
energy during the short period that it is available. All told the
system will have to collect 114 kW/h per day.

So you'll need about 933 m^2 of 10% efficient solar cells hooked up
to a 94% efficient inverter and feeding power into a 70% efficient
fuel cell in order to affect complete power independence.

Recall that you can substitute any efficiency of solar conversion
that is to your liking and thus modify the requirements I just
listed.

No matter, the solar PV requirements are going to be formidible to
achieve complete disconnection from the transmission grid.

Why even bother with this inane strategy when the same amount of
energy can be provided by 41.8 m^2 of SPS compared to the 933 m^2 of
solar PV!

Furthermore, in off-peak hours the steady baseload SPS power can be
used to electrolysize water to create the hydrogen and oxygen needed
for vehicular transit, rather than relying on natural-gas produced
hydrogen and carbon sequestration. Shouldn't SPS be an
environmentalist's dream leading to the perfect vision of a pure
hydrogen economy?

Further, what has been ignored by the environmental decentrization
advocates is the question of where all of the platinum for the
millions of fuel cells is going to come from. I grant you that if
price is no object then the demand will most likely be met from
exisiting supply but I think we all recognize that price will
continue to be a constraint.
Consider this from a fuel cell information website:

Fuel Cells: Where Will The Platinum Come From?
http://www.fuelcelltoday.com/FuelCellToday/IndustryInformation/Indust
ryInformationExternal/IndustryInformationDisplayArticle/0,1588,474,00
.html

http://www.newsargus.com/newsport/jimscars/biederman/FuelCellProblems
.html
". . . between 80 and 100 grams of platinum are needed for a fuel
cell's power output to be in the range of 70 to 75 kilowatts, or
about 100 horsepower." 100 grams (equal to a 3.53 ounces)

http://www.stncar.com/altfuel/2002pprs/00087.pdf
"According to the United States Geological Survey, the world
reserves of PGMs are estimated to be 100 million kilograms."

"To meet the boom in demand will require large amounts of capital
and a high tolerance for environmental degradation (seven to twelve
tons of ore must be processed to recover an ounce of platinum ."

So, with a total supply of 100,000,000 kg., which equates to
283,286,000 oz, and with current supply of 6,110,000 oz, we're
looking at 46 years of supply at current usage levels.

http://www.platinum.matthey.com/uploaded_files/market_data_charts/Pt%
2094%2003.pdf

To just double our usage all that we need to do is build 1.73
million hydrogen cars per year.

How likely is the hydrogen future when just the US produced
12,096,000 vehicles in 1997?
http://www.economagic.com/em-cgi/data.exe/aama/t1s5

Where will the platinum for both hydrogen cars and residential fuel
cells come from?

CITIES

Environmentalists continue to advocate this decentralized pipedream
and paint the picture of every home being an energy island but they
ignore reality when they neglect to account for the majority of the
Earth's population that lives and works in densely populated urban
environments. Where are you going to place solar PV arrays and wind
turbines in New York City? There simply isn't enough roof area for
the solar cells needed to power 20+ story buildings.

ENVIRONMENTALIST HYPOCRISY TOWARDS THE ENVIRONMENT

Solar Power Satellites are built from orbital resources and thus any
mining and fabricating have absolutely no impact on the Earth's
ecology.

To calculate the environmental impact created from the construction
of SPS we'd need to determine how many orbital launches will be
required to establish the mining and refining infrastructure in
orbit. Once that is complete then only a fraction of each SPS will
have to be launched from Earth.

Compare this environmentally friendly energy strategy to the
environmental rape that will follow from implementing a solar or
wind strategy to replace oil/coal/gas/nuclear.

To implement a large scale manufacture of silicon PV solar cells
will require silicon be pulled specifically for this purpose rather
than using scrap from the IC semiconductor industry. Here is a
glimpse into the manufacturing process.

http://www.faultline.org/place/2002/04/toxictech.html
"In 1993, Texas Instruments estimated the resources required and
waste produced in the manufacture of a single six-inch semiconductor
wafer. (In the intervening nine years, production has likely become
more efficient, but more recent industry-wide estimates are
unavailable.) Producing one wafer required 3200 cubic feet of bulk
gases, 22 cubic feet of hazardous gases, and 20 pounds of chemicals,
along with 285 kilowatt-hours of electrical power (enough to power a
refrigerator around the clock for several months) and 2,275 gallons
of water (enough for over 70 bathtubs). Each wafer's production
generated seven pounds of hazardous waste, 25 pounds of sodium
hydroxide, and 2840 gallons of waste water."

Let's not forget the environmental harm caused by mining, smelting,
fabrication, and even the transportation between these intermediate
steps for any solar or wind strategy.

This is preferred to the clean solution of SPS because the
environmental movement doesn't care as much about the environment as
they do about a paganistic ideal of living in balance with gaia.
They typically love to walk the virgin woods but would be aghast if
all 6 billion of their Earthly neighbors pursued the same activitiy.
They don't like to live in urban centers but instead prefer the
country, but would have a conniption if the city folks moved out to
the country with them.

Basically, they are anti-modernity and anti-people for there is no
way to reconcile their paganistic ideals with the necessity of
keeping the world's population alive and prosperous. When it comes
to the choice of whether to save the environment by advocating SPS
or choosing their lifestyle and damning the environment, they choose
to damn the environment.

ENVIRONMENTALIST FALLACIES

When confronted with these arguments and facts environmentalists
tend to respond in a few ways.

The first is to invoke the externalities argument. This is premised
on the fact that the traditional energy sources pollute and the
polluters don't have to pay and if those costs were properly
attributed to them then solar and wind would be the logical choices.

This is a great point to show a little humility and concede that SPS
too suffers from the externallity argument and, while currently an
uneconomic alternative, it may indeed be economically attractive on
the same conditions that are being invoked here.

Also keep in mind, that SPS will benefit from the amortization of
the orbital infrastructure across many SPS platforms. Building just
one SPS is probably a no-go option, but building the first of many
opens the SPS idea to rigorous and serious consideration.

Also, the externality argument when applied to SPS would further
trump solar and wind in the respect that they also do much damage to
the environment from the mere fact of their fabrication on Earth.

At this point the response may turn to the miniscule amount of
pollution that they would cause when considered alongside total
worldwide industrial production. Of course, this argument is
immaterial for the comparison isn't between solar/wind and
industrial output, it is between solar/wind and SPS. SPS hardly
impacts on the environment at all.

Another favorite is to attribute no change in consumer behavior or
energy use to SPS whereas solar/wind would force people to ration
energy and the resultant drop in living standards and assign a
positive value judgement to the rationing of energy. The fact that
the environment is harmed more with the rationed energy of their
proposal as against the environmentally benign SPS which can supply
generous amounts of desired power is immaterial to them. Further
there is nothing inherently good in "lowered energy use." The
external factors have to be considered. This is just a loaded value
judgement from the environmentalists.

Also beware the presumption of future technological improvement as
being the leveler. If they can't win the logical point on the merits
they'll invoke magic for the future, yet neglect to notice that any
PV technoligical improvement would equally benefit SPS.

Their favorite tactic is to claim home insulation and conservation
as benefits that accrue strictly to their plan of solar and wind
decentralization. This is simply not so. SPS would benefit just as
much from a conservation strategy as would coal and nuclear.

They also favor the tactic of painting any criticisms of their
arguments as using outdated data even when this isn't the case.
They'll invoke references from the false prophets that form the
network of incestuous amplification from which many of the
environmentalists find succor. Rarely will they tolerate a
dissenting voice if it originates outside their trusted circles.
Peer reviewed authorities are rare.

If you've managed to get them to concede on all your points thus
far, beware the final, desperate weapon - the threat of SPS
destruction and the need to decentralize our power supply to prevent
a societal loss of power.

They'll say that SPS will be hi-jacked and crashed into the Earth,
completing neglecting the amount of energy required to accomplish
this feat.

Or the operating engineers will be terrorists and turn off the
power. Why would that be the end of it. Surely, other engineers
could come in and turn the SPS back on and have the terrorists
arrested. Why not even design failsafe systems to prevent such
control in the hands of a few! Nah, that wouldn't be dramatic.

They may counter that the rectennas will be destroyed. However they
completely neglect to account for how 200+ km^2 can be destroyed.
Perhaps a portion will be damaged, but even then we're not talking
complicated machinery. These are just diodes that are strung
together. Repair is quite easy to affect.

How about terrorists crashing a space transport into an SPS or
launching a missile from Earth? Well, I'm sure that there will be a
traffic exclusion zone around a SPS and protective measures will be
followed for any transgression into the zone. As for the Earth
launched missile, it'll take hours to get to the SPS, and with the
GW of available power, it shouldn't be too difficult to have a
limited range (effective for 100 km?) particle beam attached. Just
divert a little trickle of power to the beam and destroy the missile
or hi-jacker.

Of course, if any missile is launched from Earth, the country can be
identified almost immediately and retaliatory action can be taken.
Afterall this would be an act of war.

The environmentalist equates the ability to launch a missile to GEO
to the ability of terrorists to fire shoulder-launched missiles at
airplanes. You may have to explain that there is a world of
difference in technology and scale between these two extremes.

An offshoot of the above argument is that a missile is launched to
GEO and rather than directly attacking the SPS, it fragments in GEO
orbit thus destroying everything in that orbit. This missile could
be nuclear and damage all GEO assets. Or beware the Earth-based
laser destroying a 50 km^2 platform 35,000 km away. This group of
arguments ignores the scale of distance or SPS size and even
plausability.

If you've encountered all of these arguments you'll have probably
observed a disconnect in your debate partner's ability to discern
the likely probability of an event and to calculate the expected
value of an outcome. They're probably assuming that every risk is
equal. I have no advice for you on how you can remedy this
situation, for I've tried different tactics, all to no avail.

On the basis of these flimsy rationales they'll argue that raping
the Earth and implementing their "million points of light" is a far
better outcome. They'd rather see 42.3 tons of earth crushed and
sifted to extract the 100 g of platinum for each hydrogen car, or
for each residential fuel cell of equal power.

If you enter a debate with an environmentalist beware the tactics
I've mentioned. They're loathe to concede any point to you no matter
that they are logically cornered and shown that their position is
more detrimental to the environment. Remember, they're not really
arguing to protect the environment, so you can never win the issue
if that is your goal.

The battle is really an issue of modernity and all its impersonal
confusion and technological wizardry that they abhore against their
utopian vision of paganistic oneness with gaia. SPS is a symbol of a
system they despise and all of the environmental good created by SPS
counts for nothing.

Always remember that the goal of protecting the environment is what
you're advocating and that the environmentalist will drop their
facade when asked to protect the environment and give up their
paganistic goals.

I hope you feel better prepared for battle because now you're
forewarned.

Good Luck,

TnagoMan