Hi sp, sem!
Is it possible to build an electricity generator that is driven by the
relative rotation between a gyro and earths rotation with their axes
being perpendicular? Would it be hard to get enough power to overcome
friction and get some surplus power? I guess because it rotates only
once per day it would be practical to lift a weight and turn its
potential energy into electricity every now and then rather than using a
direct generator or a speed up gear.
Dear Bernhard Kuemel:
Yes. But to gain energy from it, you will be altering the
rotation of the gyro. In short order, you will have the gyro's
axis parallel with Earth's rotation axis... and energy production
David A. Smith
I thought about mentioning that. But ... say we are at the equator. The
gyro's axis initially is vertical and is mounted in a hollow sphere. The
sphere's axis is mounted horizontally with a north-south orientation.
Now the gyro's axis will remain perpendicular to earth's axis.
Maybe there will be some change of earth's precession, but I'm not
worried about that. Hopefully it will not cause major earth quakes or
climate changes. Could we choose to either increase or decrease earths
But this means that earths axis will change until it is aligned with the
gyro. Certainly a long order process.
Maybe my description was unclear. I'll try again:
We are (not necessarily) at the equator. There is a hollow sphere with
bearings on the outside so it can rotate with its axis parallell to
earths axis. On the inside of the equator of the sphere there are 2
bearings that hold a gyro so it will spin perpendicular to the spheres
axis. Now there is no way the gyro can align its axis with earths
*current* axis, whether I extract energy or not.
Now I wonder what dimensions such a generator must have if it is to
deliver 10 kW power. Top priority is reliability because the intended
purpose is to support a facility that preserves humans at cryogenic
temperatures. I guess it will be unpractical because it has too heavy
and too many moving parts. Otherwise it would be an interesting option
because the facility could be buried and sealed deeply underground. Safe
from nukes or casual vandals. The currently best option IMO are solar
powered thermoelectric elements.
Dear Bernhard Kuemel:
No. It means the gyro's axis will be altered to match the
Earth's. The fly will move.. not (much) the mountain.
Depends on your rate of energy removal. Suffice it to say that
if it is on the order of the rate you put energy in to get the
gyro up to speed, it'll be on the same order before the gyro puts
out no more useful amount of energy.
This cannot be entirely true, if you are going to remove energy
from the gyro.
Then you will get no energy out.
Use a moon. Create a tidal generator. Better still orbit Pluto
or Charon. Plenty cold there, all the time. Not too many
Since these bodies are already dead, what does "safe" mean?
David A. Smith
But the gyro will resist to changing its axis and this torque can be
used to extract energy. If the axes must align then why shouldn't earths
axis change - just a tiny bit?
How would I do that? I don't like using the tides of the sea because I
think that's to unreliable. The facility should remain operable even if
human maintainance is absent for decades or centuries.
Yep, that might be an option. But the bodies must be protected from
cosmic rays and asteroids which would mean heavy armor which makes the
trip quite costly. Also maintainence is rather difficult. OTOH I see the
average temperature is 50 K so there isn't really a need for
maintainence. Landing on Pluto should be feasible once we are there and
digging a hole might be possible to protect from rays and asteroids. The
density of Pluto is only 1.1 g/cm3.
But then I guess it would probably take quite long until someone came
there to revive us.
Cryopreserving a body shouldn't kill. It should preserve the information
that makes up the mind so it can be scanned later and emulated in a
computer or robot. So asteroids, cosmic rays, heat, vandals, whatever
must be prevented from destroying the body/brain.