Nuclear fusion is very likely to become the power source of the future as it is able to generate massive amounts of energy from relatively cheap fuel and with little waste. The catch is that achieving nuclear fusion is not easy and researchers are still trying to find a way to ignite it without putting in more energy than the process will produce. One method to stimulate fusion though has been called into question by researchers at the Ohio Supercomputing Center.
The fast-ignition method is a two-step process that uses lasers to compress a fuel pellet to a fraction of its original size, and then an ultra-fast and powerful laser pulse to actually initiate nuclear fusion. One of the ways to deliver the laser power to the fuel is to have it hit a hollow, metal cone, causing electrons to be blasted onto the pellet but this apparently will not always work. The researchers have found that if the cone is too thick, the ejected electrons will collide with a dense plasma, causing them to lose too much energy to trigger fusion.
Actually, other researchers have found that the hollow-cone, fast-ignition method is flawed, but had failed to develop an explanation for why. While this is certainly not great news for nuclear fusion research, it is not horrible as there are still many other methods and multiple variants of fast-ignition, which still have a chance powering the future.
Source: Ohio Supercomputing Center