Solar Power Satellites.

Past a certain point, SPS studies began to focus more on PV and less on
thermal. The reason was that efficiency is nice, but launch costs dominate
everything. I think PV was judged to be lower mass, despite being less
efficient. I remember that Gerard O'Neill made the point that if one used
space resources for SPS, then the launch costs no longer predominate, and
thus thermal might very well turn out to be the system of choice. One of
his criticisms of the NRC report on SPS was that it did not address that
approach (thermal) at all, and yet referred to itself as a definitive study.

Regards,

Mike Combs
(903)-868-6314

From: Bill [mailto:qwerty172@...]

The studies of the 70's concluded that power satellites would be more
cost effective if they were a rankin cycle system, with the working
fluid being heated by solar mirrors.

Since then there has been great strides forward in solar power cell
technology.

Does anyone know what the present efficiency of solar cells are? A
typical rankin cycle power plant gets about 30-40% thermodynamic
efficiency. Is solar cells up there? If not are they substantially
cheaper to make.

Regards,
Mike Combs
(903)-868-6314

From:
Bill [mailto:qwerty172@...]
The studies of the 70's concluded that power satellites would be more
cost effective if they were a rankin cycle system, with the working
fluid being heated by solar mirrors.
Since then there has been great strides forward in solar power cell
technology.
Does anyone know what the present efficiency of solar cells are? A
typical rankin cycle power plant gets about 30-40% thermodynamic
efficiency. Is solar cells up there? If not are they substantially
cheaper to make.