Your argument seems to be though that because it hasn’t been done we shouldn’t do it.

With respect to the Bussard reactor, I would recommend you view this video:

http://video.google.com/videoplay?docid=1996321846673788606&q=bussard+reactor&total=4&start=0&num=10&so=0&type=search&plindex=0

But after many, many false starts and outright hoaxes, once bitten twice shy. Should we count our chickens before they’re hatched? (Trying to think of another corny polemic, but am worried I’ll do so till the cows come home).

When are they building the Bussard reactor? With solar and wind farms sprouting up all over the place, I can’t believe “big oil stopped it” theories to explain away why fusion isn’t already powering our world. If the Tokomak worked, why are they building another enormous 15 billion dollar test-prototype? Why is fusion still “40 years away, and always will be?” They’ve been tinkering with the Toko forever. As Bussard said, if fusion is going to work, at least we’ve funded the Toko and found that it doesn’t work. Time to move on.

The first advance is the use of artificial neural networks to dynamically adjust the confinement field; the neural networks learn and adjust to the dynamics of the plasma much better than older static algorithms did.

The second advance is that a method of eliminating edge-mode instabilities was found that eliminates heat loss caused by instabilities allowing the outer edge of the plasma to contact the containment vessel. This not only improved confinement but also reduced damage to the containment vessel and diverter and reduces the heat load on the diverter considerably.

The third major advance is that the strength of magnetic fields achievable with superconductive magnets has improves, and superconductive magnets are necessary in any commercial reactor because of sustained operation. The Chinese EAST reactor has proven the superconductive technology.

These things combined allow a reactor which achieves more than an order of magnitude over break-even to be built at power levels under 600Mw, and while 100Mw might be typical of a coal fired plant; 600Mw is typical of a nuclear fission reactor and there are generally two or more reactors at most plants.

But then going to a spherical tokamak further improves the confinement product by a factor of about 3.5, allowing still further reductions in size.

In terms of the Tokamak being dead; it is quite competitive with fission power now; even without considering that the fuel is nearly free, and only some activation products are present as waste and not high level long lived actinides. But consider those advantages and it is very competitive, save for big oil and fission interests desire to kill it.

However; what will render it unattractive is if the Bussard reactor is brought to maturity. It should reduce the capital expenses by two orders of magnitude, can use aneutronic fuel, and using aneutronic fuel power can be converted directly to electricity with no thermal conversion at efficiencies approaching 85% which is about twice that of the very best thermal plants.

The biggest electrical plants built these days are 1 GWe. The most common size is under 100 MWe.

The Tokamak is a dead end.