Saving energy is silly; the bottom line is money (was Forklifts tip

Just ignore the power collecting function. Can you station keep in
GEO with a solar sail?

Normal solar sail use has the light source and the orbital center in
the same place, the sun. By angling the sail you can get velocity
change either speeding up or slowing down. If the sail slows down,
gravity will pull it into a lower orbit.

In GEO the earth is the object being orbited around and the light
pressure is not radial from the earth.

Consider a very light sail in GEO. If it is anything but edge on to
the sun, it would be blown out of GEO and away from the earth like
dandelion fluff.

Heavy objects are accelerated one way and then 6 months later the
other way. Light power sats pick up nearly 1000 m/sec velocity over 3
months compared to orbital velocity of 1500 m/sec.

Perhaps there is a way, but I just don't see how to couple the force
vectors you can get out of a light sail into keeping a sail in GEO.

If you can, please explain how to do it.

Keith