A possible way to SSP - part 1

So, life got in the way of replying for a few days.

These are a few ideas that I have had bouncing around in my head for
quite a few years. I've thought about posting them from time to time,
but have not been game enough to, as there is one part in particular
that I suspect people will just go "he's nuts" and forget about it
(actually who am I kidding, there are a few sections where people will
think that). However it makes sense to me, if I was ever in a position
to try and set up Satellite Solar Power (SSP) this is how I would go
about it.

A caveat, I am not an engineer. These ideas have come from things I've
read over the years and given thought as to how to implement them. In
particular I've been influenced by Robert Truax, Philip Bono and Gerard
K. O'Neill. Some of the ideas have come from sources in completely
different areas.

A definition to begin with, where I talk about a Satellite Solar Power
Station (SSPS) of a given size e.g. 5 GW I'm referring to the amount of
electricity supplied on exit from the rectenna into the grid. The space
based components would be sized to take into account any losses to
generate that amount of electricity.

I'm making several assumptions. To begin with the chicken and the egg. I
think the only way cheap launchers and SSP will come about is if they
are done together, either by the one company, or a group of them that
come together with a common purpose, in a symbiotic relationship. I just
don't see someone making a cheap launcher without a large customer
requirement, and I don't see anyone trying to carry out large orbital
construction without a cheap launcher.

I also see little point in just setting out to build a single test SSPS
to prove that it is possible. While testing needs to be carried out, it
should be done as part of a larger program.

While in the long run, building SSPS and other space based construction
will be cheaper using space based resources, I doubt anyone is going to
spend the money to set up the infrastructure to allow that without there
being an existing market to try and make more efficient. Nor will they
be able to do so without some existing infrastructure being in orbit.
Therefore any initial construction would have to be carried out from
Earth, and would mostly likely continue to do so while the initial
infrastructure to take advantage of space based resources is being set
up and expanded.

For markets, I'm going to assume the whole world is a market. I would
see it as detrimental to try and focus on just North America and Europe
as potential markets. Primarily because the existing electrical
generation infrastructure is so entrenched, and secondly due to the
various legal and political objections that are likely to arise.
Elsewhere in the world -- particularly areas of high growth -- you are
less likely to run into difficulties with existing generators, and given
the need for large amounts of cheap electricity, the legal and political
objections are likely to be less.

For the SSPS I'm going to assume 10,000 metric tonnes for a 5GW system
given in one of the reference studies.

For the launcher, I'm going to assume that the cost of designing and
building two different rockets with the same level of technology but
different sizes, will be roughly the same. This comes from an Aerojet
study that I have seen mentioned in interviews and articles
(particularly with Truax) but have never been able to find (if someone
can point me in the direction of the source I would be grateful).

Related to this, I'm assuming the more technologically advanced the
rocket the more expensive it is (pretty sure it's from the same study
above).

So, in order for it not to be a test system, and to set up enough in
orbit infrastructure to drive the requirement to utilize in space
resources, I would be aiming to make a significant dent in the market
for new and replacement power stations. To my mind this means being able
to put into orbit and setting up 50 GW per year, or roughly one 5 GW
station per month -- at a minimum.

This is still small compared to the total amount that the world
generating capacity has been increasing, but should be enough to show
that SSP is a serious proposition. The rate would also be able to be
increased significantly once space based resources begin to be utilized.

To achieve installation of 50 GW per year, would require a minimum
launch of 100,000 metric tonnes during the same time frame.

That is a rather staggering amount, and the first potential roadblock.
Consider that the total annual worldwide solar panel production is
around 20 GW. If the SSPS were to use PV panels it would swamp the
market. Similar outcomes would be expected for launch fuel, and in any
exotic materials used in construction of the launch vehicles and in the
SSPS. This would likely push up costs for materials and parts required.

A couple of other considerations before I finish this email.

Going by the price data at
http://www.powerengineeringint.com/articles/print/volume-18/issue-8/power-report/global-electricity-prices-on-the-up-and-set-to-rise.html
the cost of electricity worldwide runs between about 6 and 16c/KWH. This
would suggest to me that we need to aim to supply electricity at the
lower end of that scale, preferably less. For these emails, I'm going to
use 5c /KWH as an arbitrary target. I'm going to make another assumption
as a bad case scenario, that the utilization of any electricity output
is only 50% per annum (most likely it would be around 80%) as I want to
try and underestimate any possible income.

This would mean that for every GW produced at the rectenna, over the
course of one year the income would be 1,000,000 KW x $0.05 x 365 x 24 x
50% = $219,000,000. For a typical 5 GW station $1,095,000,000, and once
we manage to get the whole 50 GW installed, $10.9 billion. If they were
designed for a minimum 30 year lifespan, and the cost remained the same,
those 50 GW would earn at least $328.5 billion.

This gives a very rough idea of income, and what we'll need to restrict
expenses to in time.

Just briefly looking at launch costs, as mentioned above for 50 GW per
year, there are 100,000,000 kg launched at a minimum. If launch costs
were $1,000 per kg, that's $100 billion, far too much. At $100 per kg,
$10 billion. Acceptable, but still too much in my opinion. If we were to
manage somehow to bring it down to $10 per kg, the launch costs would be
$1 billion, a much more acceptable figure, but much harder to achieve.

One thing to keep in mind, is that it does no good to reduce the launch
costs, if the method of doing so increases costs in other parts of the
plan by exorbitant amounts.

part 2 will follow in a day or two

Brett

On 05/07/2013 01:48, b wrote: