https://petitions.whitehouse.gov/petition/task-office-science-and-technology-policy-examine-space-solar-power-new-energy-space-goal-us/fm8kxPQt
I signed it, and I put it on Facebook. My mom signed it. I don't know if anybody else did.
Is it beyond the resources of NASA to deploy a 100m x 100m solar array in
geosynchronous orbit to produce one megawatt of power, to study
feasibility, economics and problems if any. Perhaps the space station crew
can assemble a deployable unit in their spare time, boost it to
geosynchronous orbit and then deploy it there.
Regards,
Selvaraj
On 23 March 2013 19:48, sailor.barsoom wrote:
On 3/23/13 11:03 PM, sraj wrote:
Don't be. The power density is less than half that of sunlight, and
you're not a wire mesh. You should be more nervous about going to the
beach.
- Joe
I signed the petition after a little difficulty.
We need to move up into space and we need energy.
It appears that a small space based solar power system is not practical??
Do we really need a 1Km dia transmitting antenna??..
orbit by
microwaves carries the difficulty that the required 'optical aperture'
sizes are very large. For example, the 1978 NASA SPS study required a 1-km
diameter transmitting antenna, and a 10 km diameter receiving rectenna, for
a microwave beam at 2.45 GHz. These sizes can be somewhat decreased by
using shorter wavelengths, although they have increased atmospheric
absorption and even
potential beam blockage by rain or water droplets. Because of the thinned
array curse , it is not
possible to make a narrower beam by combining the beams of several smaller
satellites. The large size of the transmitting and receiving antennas means
that the minimum practical power level for an SPS will necessarily be high;
small SPS systems will be possible, but uneconomic.
http://en.wikipedia.org/wiki/Space-based_solar_power
.. I was about to propose that we put into orbit thousands of small and
light, standardized and deployable solar arrays, of 100m x 100m typical
size, with self contained control systems. By keeping the size small it
will be possible to make the structural support relatively light.
Regard,
Selvaraj
On 24 March 2013 10:33, sraj wrote:
The only way power-beaming from smaller-scale satellites can work is by using laser transmission rather than microwave. That has yet another set of problems. But there are some researchers in Japan doing studies in that direction.
Mike Combs
From: spacesettlers@yahoogroups.com [mailto:spacesettlers@yahoogroups.com] On Behalf Of sraj
Sent: Monday, March 25, 2013 9:16 AM
To: spacesettlers@yahoogroups.com
Subject: Re: [spacesettlers] Re: Petition to examine space based solar energy
It appears that a small space based solar power system is not practical??
Do we really need a 1Km dia transmitting antenna??..
Power beaming from geostationary
orbit by microwaves carries the difficulty that the required 'optical aperture'
sizes are very large. For example, the 1978 NASA SPS study required a 1-km diameter transmitting antenna, and a 10 km diameter receiving rectenna, for a microwave beam at 2.45 GHz. These sizes can be somewhat decreased by using shorter wavelengths, although they have increased atmospheric absorption and even potential beam blockage by rain or water droplets. Because of the thinned array curse , it is not possible to make a narrower beam by combining the beams of several smaller satellites. The large size of the transmitting and receiving antennas means that the minimum practical power level for an SPS will necessarily be high; small SPS systems will be possible, but uneconomic.
http://en.wikipedia.org/wiki/Space-based_solar_power
.. I was about to propose that we put into orbit thousands of small and light, standardized and deployable solar arrays, of 100m x 100m typical size, with self contained control systems. By keeping the size small it will be possible to make the structural support relatively light.
Regard,
Selvaraj
On Mar 25, 2013, at 7:16 AM, sraj wrote:
> Do we really need a 1Km dia transmitting antenna??..
If you use microwaves from geosynchronous, something on that order is necessary, regardless of power level. This assumes a 10 km receiver.
However, if you use higher frequencies (e.g., IR laser), a larger receiver or get closer, the diameter shrinks linearly. Since IR frequencies are around (if memory serves) 10,000x or more shorter than microwaves, the minimum size shrinks dramatically. You need something on the order of a part of a football field.
Can one transmitting antenna of one Km diameter transmit 1000 megawatts of
power? Will it be able to handle the current, voltage, heating, etc.
Selvaraj
On 26 March 2013 07:26, Al Globus wrote:
Unless 98,598 people sign this in less than a week, it expires.