Earth-Moon L1

> With respect to your "First point", let us consider
> two scenarios:
> 1.) Keeping the solar cells at Earth-Moon L1, and
> landing rectenna
> equipment at some point on the Moon.
> 2.) Landing solar cells at Malapert Mountain and
> using them directly.
>
> I think your claim is that (1) has a big advantage
> over (2). I wonder.

Correct. It is at least an order of magnitude cheaper
when measured in watts per kilogram = watts per
dollar, delivered at the surface of the Moon.

> With option (1), solar cells need to be launched
> from Earth, the same as
> in option (2). With (1), additional rectenna

No. The starting point is irrelevant since it is the
same for both. The cost difference is governed by
where the cells end up.

In option 1 PV solar cells are delivered to L-1.

In option 2 PV solar cells are delivered to the
surface of the Moon.

Option-1 is at least an order of magnitude cheaper.

Watt for watt, the additional cost and weight of the
rectenna is very small compared to the cost/weight of
the associated solar cells.

> equipment and the means to
> deploy it must be launched from Earth and landed on
> the Moon. With (2),
> solar cells need to landed on Luna.
>

Five times more equipment is needed for deploying a PV
array than for a rectenna of comparable power, see
below.

> How many square kilometers would the rectenna in
> option (1) cover? What
> would the mass be of that area of rectenna? What

The rectenna will cover about five times less area
than an equivalent array of PV cells, assuming
rectenna efficiency of ~95% and PV efficiency of ~20%

> kinds of machinery
> would be required to deploy it over that area, and
> what would the mass be
> of those robots? Do you still think that combined
> the it would be a lot
> less mass than landing solar cells directly on the
> Moon?
>

The equipment needed for deploying PV array and
rectenna are about the same. Deployment of the
rectenna can be done five times faster or with five
times less equipment for the same time, because teh
area it needs is five times less.

>
> Another point.... it is possible to conceive of a
> plan to start
> bootstrapping at Malapert Mountain. Land the
> minimal amount of robotic
> equipment necessary to begin manufacturing solar
> cells from lunar
> materiel.
>

Sure. But a machine to build a rectenna will be
cheaper, simpler and lighter.

Cheers,

Charles R.