Robert Bussard’s Polywell Fusor design is incredibly exciting for any space enthusiast because it promises REAL atomic power for spaceflight. Sure fission rockets have been “atomic power” in our minds since the late 1940s, but any fission reactor is such a cranky system and only offers thermal power generation options. Aneutronic fusion – the burning of Lithium-6, Helium-3 or protium-Boron-11 – offers something utterly different: direct energy conversion. In the case of p+B11 => 3He4 fusion/fission reactions the energy of the produced alpha particles can be turned into electricity at ~ 95% efficiency. This is a real breakthrough – or will be when Bussard gets proper funding – as electrical power can be used to heat reaction mass via relativistic electron beam guns. Ionised exhaust and no thermal contact with the reaction mass means the exhaust velocity can be pushed a lot higher, thus the vehicle can use just plain water as reaction mass.
Thanks to Askmar (Emerging Technology Marketing) Bussard’s papers are available online for all to see…
IEC Fusion at Askmar
…have a quick browse, but for specific breakdowns of Bussard’s estimated costings of
- A 4000 person colony on the Moon
- A 1200 person colony on Mars
- A 400 person colony on Titan
…all for less than the NASA budget over the same time period, then check out this one:
System Technical and Economic Features of QED-Engine Drive Space Transportation
…QED being “Quiet Electric Discharge” or Monster Electron Guns blasting stuff into plasma Engines.
The transformation of the world’s power economy is a little bit harder to discern. Firstly, to minimise replacement costs and timelines Bussard proposes using D-D fusion for power extraction via the neutron flux. Neutrons would heat water, and that would directly hook-up with regular steam-plant at a pre-existing coal/fission power-plant. All new power-plant could then use aneutronic fuels and minimise thermal losses by direct power conversion.
All sorts of liquid fuels could be made using a fusor at some point in the production cycle, without any greenhouse emissions being needed. Ethanol or methanol are good options, but eventually battery/ultra-capacitor technology might make liquid fuels an irrelevance. However hydrocarbon engines are so power dense it’s hard to see just how successful that transition will be. Fusion heating could make extracting oil from very marginal deposits highly practical and fusion-powered atmosphere processes could draw-down carbon dioxide directly from the atmosphere. In fact it’s perfectly feasible to re-form hydrocarbon fuels directly from water-and-carbon-dioxide exhausts via fusion energy. Thus oil, as a high-density energy-storage medium, might never have to be abandoned, even if it does have to be made PURE GREEN via fusion power. After all oil is essentially a natural product, used by virtually all living things to store energy – we know it as “fats and oils” as part of a healthy diet.
A suitably high energy density storage system would make small electric aircraft perfectly feasible, and a large aircraft could have on-board fusors and essentially infinite range. By extracting deuterium from the atmosphere an aircraft could stay aloft without refuelling, resupplied by small shuttle planes. Such a system might allow larger luxury air-vehicles to fly continuous routes, loading and unloading via shuttles from airports along the way.
Once Robert Bussard’s work is completed with a working power reactor then we’ll know if fusion power will yet save the world.
