Science Forums 2

[CraigD]

Originally Posted by Roadam

Antimatter would be great if we would know how to produce it efficiently. At the moment I think the number stands at about a few percent.

According to Robert Forward’s 1995 IMHO classic popular science book “Indistinguishable from Magic”, antimatter factories are about 0.000003% (1 in 60 million) efficient. Including the cost of the factory and its operation, the present cost of antimatter at about ten trillion dollars per milligram. The present production rate of antimatter is about (one trillionth of a gram per day).

Originally Posted by Roadam

So if efficient conversion would be possible, one could build large power plant of some sort(solar, fusion, fission,... whatever). And use the energy to produce and store antimatter. Containers could then be loaded onto a starship and there you go, fast space travel.

In the same chapter/essay (chapter 1), he cites a study he did for the US Air Force concluding that, if a factory were designed carefully to maximize production (present day factories are based on accelerator/collectors designed to provide the maximize useful scientific data), the efficiency for on-grid, Earth-based factories could be improved to about 0.01% (1 in 10 thousand). The resulting cost is about ten million dollars per milligram, though production rate would still be too low to meet present day spaceflight demand. Still, assuming a first-generation antimatter powered water steam rocket, such a cost would be about 1/10th the cost of current chemical rockets for routine tasks such as orbiting satellites and sending spacecraft to other planets.

To produce antimatter at sufficient rates for routine space travel, production would need to be on the order of 1 g/day. According to Forward, this would require space-based factories with the equivalent of a present-day photovoltaic panel 100 km by 100 km at 1 Earth’s orbit (AU) distant from the Sun (which would equate to about 1/7th the area at a distance of about 0.38 AUs, just inside the orbit of Mercury.

My views on the subject are pretty close to Forward’s.