The suburb of Lucas Heights, just over 30kms from the Sydney CBD, is home to Australia’s only nuclear energy facilities – an old one, and a recent replacement. Commissioned in the 1950s, the HIFAR (High Flux Australian Reactor) was designed to test nuclear materials by exposing them to a lifetime of neutron radiation in a very short period. Based on a plant in the UK, it was one of many reactors constructed primarily for research purposes, and is the last operational facility of that particular design left in the world. In 2006, HIFAR was superseded by a new reactor at the same site called OPAL, based on a greatly modernised design, and in three years’ time HIFAR will be shut down permanently. There are currently no plans to expand the nuclear generation capacity in Australia beyond this new reactor.
But Australia has a wealth of nuclear fuel, in the form of naturally occurring Uranium deposits, which are actively sold overseas to countries which rely to a much greater degree on nuclear energy to meet their needs. So, why is Australia apparently not interested in the potential for an emission-free source of energy that could continue to meet our growing demand for energy well into the future?
Mention nuclear energy, or as it was once known “Atomic power” to most people and their immediate response will be to think of the disasters involved in power production using nuclear fuel: Fukushima and Chernobyl: The worst civil nuclear radiation events in history. If they read a lot about nuclear issues, they might even mention Sellafield, a facility in the UK that processes spent nuclear fuel in order to make it safer to store. But what are the real risks and benefits of nuclear energy generation? First we will look at the risks, and then we can look at the benefits, and the future.
First up, nuclear power conjures up images of mushroom clouds and Hazmat suits. But what is it? In the mid-20th century, scientists first devised a way to release a massive amount of energy from a small amount of material by splitting atoms. This reaction was effectively uncontrollable, and was initially used as a weapon which helped put an end to hostilities in the Pacific in the Second World War. But it was almost a decade after the end of WWII that the first nuclear energy generation plant became operational using nuclear fuel to produce heat, which in turn produces steam that drives the turbines that produce electricity. In this way it’s no different to coal fired power stations that burn coal to do the same thing.
That original nuclear plant and all existing plants, numbering around 500 worldwide including those still under construction, use a process of nuclear fission. That is, the splitting of large, heavy “radioactive” metals, such as plutonium and uranium. While much more efficient in terms of fuel than coal fired power stations, these reactors still only used between 0.5 and 5% of the available energy contained within the fuel. What is left over afterwards produces high amounts of ionising radiation, and must be stored for hundreds of thousands of years in safe facilities to avoid contaminating the environment. Ionising radiation is that which causes mutations and radiation sickness in living things.
Disasters like the Fukushima leak and the Chernobyl meltdown are examples of failures of the containment systems of nuclear reactors that have allowed radioactive materials to escape into the environment. This is obviously a major concern when nuclear energy is generated near human settlements. The decision to utilise nuclear reactors based on uranium and plutonium fuels was at least partially due to the by-products of fuel processing being useful for the construction of nuclear weapons. These old style, water-cooled reactors have the potential for radiation leaks when safety mechanisms fail or are deliberately disabled, as was the case in Chernobyl and Fukushima. But this is not the only way to produce energy from nuclear fuel.
Uranium and Plutonium fuelled nuclear reactors are the most common type, and also potentially the most risky, but more recently developed technologies using different fuels, such as thorium, and different reactor designs, including sodium-cooled reactors, have the potential to be built on smaller scales, and produce energy in such a way that the risk of “meltdown” are absent. The new generation of reactors are not capable of continuing to function if something goes wrong, and shut down by design.
The next generation of reactors also release upwards of 90% of the energy contained in the nuclear fuel, and can even re-use fuel from older style reactors, greatly reducing the production of waste that needs storage. The length of time storage facilities are required is also reduced, from around 300, 000 year to about 300 years. This is still a long time, but a conceivable period for engineers to work with.
The main reason nuclear is coming up as a potential energy source is the low emissions produced by nuclear stations. Compared to coal burning, nuclear stations produce less than a tenth of the greenhouse gas emissions to produce the same amount of electricity. While many people focus on the risks associated with nuclear power, historically it is one of the safest forms of power generation ever utilised, comparing deaths per Terawatt of energy produced, nuclear has a miniscule fraction of the danger associated with almost every other form of energy generation.
Nuclear fission is a relatively simple process: take big atoms, break them into smaller ones to release energy. The opposite process also releases energy: taking smaller atoms and mashing them together. This process is called fusion, and it’s what makes the sun shine. Fusion reactors have been shown to work, but the reaction fizzles out after a short period, and usually more energy is required to keep the reaction going than it gives off. But if we can find a way to sustain fusion reactions, we could have a potentially unlimited source of energy. The most promising research uses a type of helium, but unfortunately there’s not a great deal of that particular type present on earth, so progress is slow.
But in the short to medium term, it may certainly be useful for Australia to investigate the possibilities of installing next generation nuclear reactors. Without relying on water for cooling, reactors could be situated anywhere in the country. And with the high tectonic stability of the continent, it would be easy to find sites that have very low risk of earthquakes or similar natural disasters. As a component in the energy mix, including renewables, there seems to be little reason to ignore nuclear energy for Australia’s future. To find out more about a current energy plan to suit the needs of you and your family, compare providers and switch today to save.
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