Kalam Kinetic Battery

I presented Server Sky and Launch Loop to ISDC, the International Space Development Conference, in Chicago in 2010. The "video guest of honor" was Dr. A.P.J. Abdul Kalam, the rocket scientist who developed India's first space launch rocket, and was president of India from 2002 to 2007. Not bad, for an apostate Muslim and Tamil technical geek! Dr. Kalam gave a video linkup presentation about space solar power for India, and answered questions afterward (not enough - the AV people cut him off for the next session. FOOLS!).

I briefly mentioned Server Sky, and asked about providing data service to rural India. Dr. Kalam started riffing about providing batteries for children's computers, delivered from space. Or at least that is the way it sounded with my hearing problem. It did not make sense at the time, but it led to this idea, so I will give him credit.

Space solar power is very difficult to do. The power can be collected with large arrays of thinsats, like server sky except optimized for power transmission rather than computation. Energy on the ground can be stored in PowerLoops. But sending power from orbit to the ground is nearly impossible. The best idea people have had so far is sending down beams of microwaves from gigantic antennas to gigantic receivers on the ground. This would be ridiculously expensive, inefficient, interferes with GEO satellite communication, and is damaging to wildlife (and people) caught in the beam. It might be better to use 20THz infrared, but we don't know how to do that efficiently, and atmospheric transmission is poor.

So why why not send down batteries? Not literally, chemical batteries have low energy density, and getting the discharged ones back up to be charged would require far more energy than they store, even with launch loops launching them up there.

So instead of using chemical batteries brought to the surface, we can instead send down "kinetic batteries", iron bolts much like John Knapman's space cable bolts, at very high speed and containing a heck of a lot of kinetic energy. In honor of Dr. Kalam, I will call these Kalam Kinetic Batteries.

Imagine a vertical bolt accelerator, very long, in an orbit a bit below geosynchronous, but in a 24 hour orbit. How does that happen? A lower than GEO "24 hour orbit" will soon fall towards earth, an ellipse with shorter than 24 hour period. But what if we add centrifugal force by firing a heck of a lot of bolts downwards at very high speed?

The inwards radial velocity and tangential velocity of the bolts can be designed so they miss the earth, almost, grazing above the atmosphere at perhaps 110 kilometer altitude. There, they are precisely (VERY precisely) steered into the mouth of a linear decellerator; they are slowed, energy is taken out, and they exit the decellerator at much lower speed, in an elliptical orbit takes them back to the top of the accelerator. We can move hundreds of megajoules per kilogram of bolt this way.

The trick is managing the angular momentum of the bolts thoughout their journey; obviously, we can neither add nor subtract large amounts of angular momentum from our accelerator in orbit, or the geometry of the orbits will no longer line up. MORE LATER

The other trick is that we must aim and orient the bolts VERY precisely. We have a few tricks - the bolts can contain GPS-like receivers and location transmitters, and can track their position down to the millimeter with server sky tracking arrays. Near the earth, they are passing through the earth's magnetic field, and we can modify their trajectory (slightly) by charging or discharging them with a distant electron gun. We and also play tricks with light pressure, by rolling mirrored surfaces into solar (or power laser) light pressure. We don't want to expend reaction mass, unless we stop them at the near-GEO station for refueling, but we still have many degrees of freedom.

MORE LATER.