Energy and in particular electricity has become a topical issue in Australia. This is because of high retail electricity prices but also because of issues with reliability. It is in that context that Senator Cory Bernardi has put before the Australian Senate a bill to end the prohibition on nuclear power in Australia.
But, is nuclear power really the answer? Isn’t nuclear power dangerous and expensive? A tired old technology promoted by tired old conservative politicians with some strange sort of tired old axe to grind? Certainly these propositions are promoted by opponents.
However, I contend that the nuclear energy sector is entering a period of not just rapid but radical technological change. This innovation is still mostly on paper and won’t be visible for several more years but it is certainly coming. As a nation we need to be both open to it, and ready to embrace the exciting possibilities that it represents.
Conventional nuclear reactors use water as a coolant. They operate at a temperature typically around 350°C. If you recall any high school physics then you know that at that temperate water is normally a gas and to keep water which is that hot in a liquid form it has to be highly pressurised. In a reactor this water is usually at about 150 times normal atmospheric pressure in order to make it remain as a liquid. The reactor vessel needs to be made of very thick steel to contain such pressures and avoid accidents. Very few places in the world can make such a thick steel vessel and they cost a lot to make. The purpose of the water as a coolant in these reactors is to carry heat away from the reactor and to deliver that heat to some sort of turbine system that can turn the heat into wonderful electricity.
However there is a big challenge with these conventional designs. If you have an accident with such a reactor, say a pipe bursts, then the hot coolant water turns to hot steam and as it goes from a liquid to a gas it expands rapidly. It will expand in volume by a massive factor of over a 1000. And because this coolant water may carry radioactive particles it needs to be contained to keep the public safe. This highlights a safety concern with current reactors that must be managed. In the USA the regulator proscribes an emergency planning zone of a 10 mile (16 km) radius around such a reactor. Rightly or wrongly they take a very cautious view of things.
Of course if you give engineers enough money they can make almost anything safe. Our homes are full of deadly electric wires full of high energy subatomic particles but these wires are contained and managed in a way that is so safe that we think nothing of it. To make a conventional nuclear reactor safe from a leakage of coolant water engineers construct a massive containment building 1000 times bigger than the reactor inside. Google some photos of nuclear power plants and you will see how large they are. And that large concrete containment structure, which in normal operation is filled mostly with just empty space, is both part of managing the safety risk from the coolant water but also a very big part of what makes nuclear power plants expensive.
If reactors could be designed so they didn’t need that large concrete containment building, and if they could operate at low pressure without any driving forces wanting to liberate radioactive particles out into the world, then nuclear power plants could become the cheapest form of electricity on the planet. The exciting thing to learn is that we don’t need to use water as the coolant. There are safe alternatives. And this is not just theoretical; it has been technically proven. We simply don’t need to use water!
Now there is a very big race occurring. Nuclear engineers have awoken to a huge opportunity brought about by accelerating global demand for affordable electricity, and by insights on how nuclear power could become intrinsically safe whilst at the same time getting radically cheaper. Some nuclear engineers have already ditched their long comfortable careers on reliable salaries and turned entrepreneur. Private equity is sponsoring an array of new companies. They have names like Terrestrial Energy, Moltex Energy, ThorCon, Elysium Industries, Flibe Energy and many, many more. Two of these have already started the regulatory process to license their new reactor designs in Canada and so far the public comments suggest that the regulator has been cautiously impressed.
All these companies have a design based on the same essential insight: use something other than water as the coolant. And use a fuel that won’t liberate radiation into the wind even if you stuck a wrecking ball through the joint. The coolant of choice for these innovators is a mundane substance we all know. Salt. Get it hot, and molten salt is a liquid that looks like water, flows like water, but which can remain a liquid even at normal pressures. And if a pipe bursts it does not gush out and turn to gas and catch the wind but instead it drips to the floor and then quickly turns solid. What a difference scenario!
Removing water from the coolant process lets you design a reactor that doesn’t have to be at high pressure. It lets you avoid an expensively thick steel reactor vessel. It eliminates the need for a very large and expensive concrete containment building that is mostly empty space. It means that even if the vessel cracks open the contents just flow to the floor and turn solid. Reactors that are vastly safer and vastly cheaper are now possible.
But wait there’s more!! These new designs can extract 40 to 50 times as much energy from the same amount of fuel. So they produce far less nuclear waste. In fact some of them even burn their own nuclear waste. And they can even burn the stock piles of waste we have from 50+ years of conventional nuclear reactors and make electricity out of it for decades to come.
There are many other innovations in the works. New fuels are coming for the traditional fleet of water cooled reactors that will make them a bit safer and a bit cheaper as well, but Australia is in a position to leap frog that old world of nuclear and dive into a new world of truly cheap, reliable and clean emission free atomic electricity.
Do we really want to be a nation of tired old thinking that misses the boat on a new era of innovation? One that sticks with the tired old tactic of total prohibition? Or do we want to set aside old fears, open ourselves to new possibilities and look again with fresh eyes? I want a future for Australia and the world that is both clean and rich. What do you want?