As a child you often dream of saving the world, I’m sure. Yet, science labs and the workrooms of mathematicians are hardly the world of comic book superheroes, even though it is these leading experts who will in the end save this world of ours.
Fusion energy is now in the hands of scientists and mathematicians who seek to prove its feasibility as a future energy source.
Experts believe fusion energy can:
Fusion scientists are close to saving the world from annihilation, either from man’s dirty industry or man’s maniacal desire for world domination. Such is the hope attached to such technology that a lot of the wider world refuses to believe it can be true.
Nuclear Fission, along with wind, solar and hydroelectricity, is the power source we have come to accept as the solution to the energy gap. This energy gap is a result of a demand for a reduction in the reliance on fossil fuels, with legislation to lessen carbon emissions. The gap is also widening, as the energy demands of the world quadruple. In nuclear fission reaction is fuelled by uranium and plutonium, which produces neutrons, which in turn creates radioactive waste. These fuels are chosen for their ability to produce the necessary heat for reaction, which in turn produces energy.
Aneutronic Fusion energy instead uses boron with hydrogen. Boron is the 10th most abundant element, dissolved in sea water. Hydrogen is the most abundant element in the universe. Helium, the light gas pumped into the vacuum, is harmless. Add in a spark of energy that you hope to be magnified by fusion – and a cheap, clean energy source is born.
As the resources needed to fuel the reaction are so plentiful and readily available, the cost is approximately $60 per GW as opposed to the $1000 per GW of current energy sources. Wit small local distributed fusion onboard your energy bill can all but evaporate and so would for plenty of businesses which now could offer you a discount on their goods and services based on that cost.
The reaction of boron with hydrogen creates three helium nuclei, also known as alpha particles. Therefore, there is little harmful radioactive waste – in fact less radioactive waste than coal power stations. Evidence suggests that within nine hours of shutdown radiation has returned to background levels. The only waste produced by fusion is ionised gas. Why is it still theory and not practice? This fuel is twenty-five times more likely to produce x-rays. The result of these x-rays is to cool the electrons, which in turns prevents a net gain in energy from the reaction. In short, it doesn’t work, yet.
So, the good news is that we have millions of years’ worth of boron. This fuel is environmentally safe, with no carbon emissions and no radioactive waste. The bad news is that this is largely useless unless scientist can find a way of extracting the energy from the reaction of ions with electrons.
The oldest joke in fusion research is that we are still 50 years away from fusion power, and we said that 50 years ago too. The physics involved in fusion is not new, in fact the concept of a fusion focus device was established about a century ago. This is essentially the process used by the Sun to create its enormous energy reserves. Electricity is used to superheat helium and create a plasma beam that is then harvested by a transponder coil. Energy in, yes, but then hopefully a massive increase in the energy out.
What is happening in energy development today is a reapplication of these ideas observed in the sun, in what scientist deem to be a cleverer way.
The Tokamak is the largest and most well-known application of fusion technology. Tokamak emerged from the USSR in the 1960s and works on the principal of creating a stable plasma equilibrium. The US government are currently directing funds into the ITER project in southern France. This an unprecedented collaboration between Europe, America, Russia, China, India, Japan and South Korea. This is a massive project and has become something of a money-pit. The costs have spiralled and the project is some 10 years behind its own timetable.
It takes a huge amount of power to trigger the reaction and to then contain the energy beam using a magnetic field. As yet, along with all other fusion devices, the ITER does not achieve a net gain in energy and governments are losing patience with its under-performance.
The proposed timetable for this net gain, and therefore the creation of a new energy source, is now 2050. At this point, the Tokamak is merely a device that proves fusion energy is feasible. The large and expensive ITER will have already served its purpose.
The Dense Plasma Focus is similar to the Tokamak in the sense that it uses a capacitor to pulse energy into a vacuum filled with gas and to then focus the beam of energy in a magnetic field towards a transponder. However, unlike Tokamak, the team behind Dense Plasma focus do not believe the answer is to create equilibrium but instead harness the instabilities. This is counter intuitive to most scientists.
DPF first emerged in 1964 as an alternative to the Tokamak. NASA offered funding because of the possibilities that it was a fuel option for a mission to Mars. As the system is so small, only the size of room, it was felt this was a good option for the shuttle. Funding dried up until a boost in 1994 from JPL and then again funding in 2001. This haphazard funding model has been largely to blame for the DPF still only being theoretically possible. The 2001 model showed that they need to scale up yet again in order to achieve a higher confinement of the beam, but there was no money available for the engineering of such a unit.
So, in detail, how do they propose DPF would work? Two cylindrical electrodes, only a few inches across, are used. The main unit can be held in your arms. One is placed inside the other and then placed in a vacuum chamber. The vacuum chamber is the size of a room. The vacuum is filled with a light gas. A capacitor bank then sends a pulse of electricity into the chamber, which discharges across the electrodes. For a millionth of a second an intense beam fires between the outer and the inner electrode. This ionises the gas between the cylinders. Unlike some theories, that attempt to control plasma, focus fusion works to harness the instabilities. Plasma was given its name because it works like a living entity, as in plasma within blood, and therefore it resists controls. By using the instabilities, focus fusion works with plasma and does not try to work against its natural state.
The instabilities in the reaction are three-fold. First there is the pinch, where the dense filaments compress and form whirlwinds and are pulled through the inner cylinder. Here the filaments converge and focus before the final instability: a kink, forms like a tangled donut – known as the plasmoid. From this the beam of ions shoots in one direction and the electrons in the other. The beam reaches thousands of degrees in temperature: an intense burst of energy. This pulse is already electricity and when directed to a coil transponder can be transformed into cheap and readily available energy. A magnetic field is introduced to focus the beam and protect the electrons from x-rays. The ions then stay hot enough to allow the fusion reaction.
The DPF (dense plasma focus) technology needs about $10 million to achieve scientific feasibility. The engineering of the power plant, said to be no bigger than a room, will take just $50 million. It is thought in the future that this technology could be built within neighbourhoods, with no need for the creation of a grid. With no radioactive waste and no emissions, the power plant can be built close to houses. It is thought that once tried and tested these would cost as little as $300,000 for each 5GW unit.
To ensure the success of fusion energy the scientists still have to overcome a number of challenges. Can they heat the ions to a sufficient temperature so that there is a reaction with the electrons? Can they retrieve the energy of this reaction? Can the density of this energy be sufficient to offer a net gain in energy? Can the energy be suitably contained?
The first tests revealed that it was possible to get the temperature to well beyond the one billion centigrade needed for reaction. With further development and testing the energy was harnessed using a coil transponder. It was theorised that the harmful x-rays could be harvested using photoelectric technology. It was also theorised that the usefulness of hydrogen boron could be scaled up to provide a net gain in energy. The important word here is “theorised”. Funding was redirected and those developing the technology are having to use literature and mathematics to work towards the scientific feasibility of fusion rather than engineering the technology and testing.
50 scientists recently signed a letter to the US government asking for a broadening of funding to a wide range of fusion devices, after the 2013 presidential budget that redirected funds to Tokamak. Tokamak is a fusion power plant being built in Europe with international money. It is massive in scale, unlike DPS, and therefore a money pit and a time consuming engineering project. It will take years for Tokamak to function and its only aim in 2050 is to prove that fusion energy can be harnessed. So, the biggest challenge fusion scientist face is finding the money from other sources to turn theory into reality
There are other projects that are finding funding from these other sources. DPF has been given only an initial $500,000 investment from NASA and is was raising money using crowd funding on Indigogo. It is a long way towards its funding target to achieve scientific feasibility. The FRC-CB has received $40 million from Paul Allen of Microsoft and Goldman Sachs. It is thought the Russian government has also recently invested in this project. The project IFC has been given $6 million from DARPA and the Navy. Both of these projects, FRC-CB and IFC, with their private funding, are highly secret and have only made vague statements about their pleasant surprise at the results emerging from the use of hydrogen boron.
And from this funding competition, the fusion race is born. And, still scientist smile when they hear that we will have fusion power in the next 50 years. Why? Well, that’s what they said 50 years ago. The Focus Fusion Society therefore hopes it will be successful in disseminating both funding and research outcomes, to make real what people think is a pipe dream.