Milestone Update - Jan 5, 2011
An update of LPP’s progress so far along the 8 milestones.
Milestone 1: Achieve pinch on FF1 machine
This milestone was achieved before the milestone update in November 2009.
Milestone 2a: Achieve pinch at 25kV and 1MA
This milestone was achieved before the milestone update in June 2010.
Milestone 2b: Determine optimum gas pressure
We have begun to work on this milestone but have not completed it because what is optimum depends on the maximum current and pulse timing. Problems with the switches caused us to fire FF1 in many different configurations for which different pressures would have been optimum. We now have more stable firing that is allowing us to close in on optimum values.
Milestone 3: Test theory of axial magnetic field
This milestone was partially achieved before the milestone update in June 2010. However we are still determining the extent of the axial field effect and the optimum values for the field.
Milestone 4: Achieve pinch at 45kV and 2MA with deuterium
Switch prefiring has prevented us form achieving 45kV and not being able to fire with 12 capacitors has prevented us from achieving 2MA. We hope to achieve this milestone soon after the trigger electrode revision is done.
Milestone 5: Confirm Texas results with better instruments
In December we collected the last piece of evidence to prove that what we saw in the Texas experiments (and can now reproduce) was definitely confined 100keV ions.
Milestones 6-8 have not yet been achieved. The explanations below were in the previous milestone update, but they are good explanations so I decided to reuse them.
Milestone 6: Optimize for heavier gases
Deuterium has an atomic weight of 2. A 50/50 mix of hydrogen and boron-11 has an average atomic weight of 6. There are some plasma parameters that depend on the atomic weight of the particles in the plasma. As we shift to heavier atomic weight we will need to adjust the length of the electrodes, the initial fill pressure, shot timing, etc. to maintain optimum plasmoid conditions. We will do this by mixing in nitrogen (atomic weight 14) to add weight without adding the complexity of nuclear reactions.
Milestone 7: Achieve fusion with pB11
This is an important step where we switch from the nuclear-inert gases helium and nitrogen to boron that can fuse with protons. If we achieve our previous milestones and create plasmoids with high enough temperature and density then fusion should just happen and this milestone won’t require any additional adjustments, but it will still be nice to finally see it happen.
Milestone 8: Achieve positive net energy
Obviously, the goal of this work is to create more energy than we consume. Here’s how we plan to do this. The capacitor bank in FF1 holds about 100,000 Joules of energy. When we flip the switch that energy goes in to the electric currents and magnetic fields in the plasma. The energy isn’t gone, it’s just in a different form. Then fusion reactions add energy to the plasma. For this milestone we hope to create 33,000 Joules of fusion energy with each shot. Then that 133,000 Joules of energy has to be converted back to electricity. But it can’t be converted with perfect efficiency. There will be some losses. If we can get 80% of that 133,000 Joules back into electricity then we will have 106,400 Joules of electricity. That’s more than we started with. 100,000 Joules can be sent to the capacitors for the next shot, and 6,400 Joules can be siphoned off as power output. This experiment won’t actually convert the plasma energy back into electricity, but by measuring the plasma energy we can show that we could create a power producing reactor. That is what we mean by the term “demonstrate scientific feasibility of energy production” and that’s the goal of this milestone.
We have completed 3.5 of our 8 milestones. We are a year behind the original schedule, which can mostly be blamed on the switch problems, but we are making good progress. In 2011 our plan is to finish the trigger electrode revision, which will allow us to achieve 45kV and 2MA, optimize the gas pressure for that configuration with deuterium, switch to helium and nitrogen while continuing to optimize, then switch to hydrogen and boron. At that point we hope/expect to see a shot that generates 33,000 Joules of fusion energy, and all of our milestones will be complete. Unless we run in to more unexpected problems it is realistic that we might finish that by the end of the year.