Selling power-service at non-competitive prices (was RLV marginal co

> In the meantime since I last posted, I found the answer in the
> SSI_list archives:
>
> "IIRC, GSO/Mars/Luna would be 7x LEO cost or $3,500/kg"

Again with the quoting people (me in this case) out of context.

The x7 cost is based upon two RLVs refueling in Earth orbit and acting as a
two stage booster. It's a minimum investment way of getting to the moon. For
SPS we'd want to use something a little more exotic than LOX/LH. The NSTAR
engine from Deep Space One approached an Isp of 3000s (Wiki says) & LEO to
GSO is 3.8kmps. MR=0.129 So an extra 13% added to mass and payload.

> > At ten cents/watt delivered cost for the electricity, the
> > SPS would earn one billion dollars/year
>
> At 10 c/kWh busbar, a generating station would not be able to compete.
> http://www.world-nuclear.org/info/inf02.html

Odd thing about that page. The price does not include disposal, which is
already very expensive.

Odd thing about SPS. Possibly I'm under estimating construction costs (heck
knows there's wriggle room there) but my numbers always come out better than
coal. Maybe because I use UK prices. I always amazed when Americans somehow
forget that other parts of the world might use electricity too. Sure you're
trying to light up your own nation, but it's really ####ing stupid to *keep*
*forgeting* this from a PoV of raising initial capital.

Since you liked my quote above, here's another; this time something I wrote
for the SPS wiki page:

"Current prices for electricity on the public grid fluctuate depending on
time of day, but typical household delivery costs about 5 cents per kilowatt
hour in North America. If the lifetime of an SPS is 20 years and it delivers
5 gigawatts to the grid, the commercial value of that power is
(5,000,000,000 watts)/(1000 watts/kilowatt) = 5,000,000 kilowatts, which
multiplied by $.05 per kWh gives $250,000 revenue per hour. $250,000 24
hours 365 days 20 years = $43,800,000,000. By contrast, in the United
Kingdom (October 2005) electricity can cost 922 cents per kilowatt hour.
This would translate to a lifetime output of $77$193 billion for power
delivered to the UK."
http://en.wikipedia.org/wiki/Solar_power_satellite#SPS.27s_economic_feasibil
ity

Closer to $4B a year for the ten gig model Gary was talking about - even at
$0.05/kWh.

> "US cost figures for 2007 published by the Energy Utility Cost Group...

Are not publically. Google it and you just get the page you're quoting from.
Which again does not include the costs or address the problem of long term
storage.

> > I expect we could derive useful energy from an SPS for
> > about a century,
>
> Ditto for nuclear. Every 20 years, estimated reactor lifetime gets
> extended 20 years. Right now, most new reactors are designed for 60-
> year lifetimes (70 years for Japan's reactors), and there is talk of
> extending that to 80 or 100 years.

The problem is not reactor lifespan but global uranium reserves.
Specifically that they are limited, however clever you are about
reprocessing. We're living the fun and exciting adventure of what happens
when you need to switch fuels. US estimates of another 200 years of fuel
again fail to recognise the fact that other nations in the world will
(unfortunately) copy America's energy strategy. Start to ramp up ractor
numbers and a typical 200 year estimate goes down hill very quickly. Do we
really want to face the whole sorry mess again in another generation or two?

And all those "Don't worry - we're experts" reasurances ring hollow for 75%
of future reactors, as they'll be beyond US control.