[ExI] Power satellites

[BillK]

On 4/25/09, John K Clark wrote:
<snip>
>  You can't know that, in the power satellite business we don't even know
>  what we don't know so nobody can pin a cost number on it. About the only thing
>  we could say with any confidence is that it would be the most expensive object
>  ever made by the human race.
>

I agree that there are probably many unknown unknowns in a project of
this scale.

But the main thing I don't like is the timescale of 15 to 50 years.
How can you guarantee funding and political will for a project like that?

PV cells are improving month by month, becoming cheaper and more efficient.
By 15 years time, I would expect every building to be off the grid,
using spray on PV cells. And who knows what other energy improvements
will come along in that time period.

By the time it gets half built, people will be wondering whether they
should be spending all this money on a project that is looking as
though it might not be needed after all.

BillK