What's the deal with nuclear power?

Nuclear power is a dirty name in Aotearoa and across the globe. How does it really work?

A few months ago, The Detail did an episode looking at Aotearoa's goal to get to 100 percent renewable electricity.

Interestingly, the most common piece of feedback wasn't about renewables, or fossil fuels. It was about nuclear power. 

"Your article was interesting," wrote one listener, Derek, "but made no mention of nuclear fusion [which] will be the ultimate solution to replacing fossil fuel fired power generation for the entire world."

Another listener, Andrew, pointed out the same thing: "[nuclear power] is the lowest carbon intensity, according to IPCC work ... but persona non grata in New Zealand?"

Nuclear power is an interesting proposition for the world - though less so for New Zealand. 

Its greenhouse gas emissions are, indeed, very small, once a plant is open and operating (it's worth mentioning nuclear plants come with high 'overheads', both financial and in terms of carbon emissions, as they require enormous amounts of concrete and other materials). 

Nuclear reactors produce reliable baseline electricity cheaply and efficiently.

Yet they're thought of as dangerous - and, in a sense, fair enough: nuclear power was discovered because scientists wanted to develop the most devastating weapon ever created, and the spectres of Three Mile Island, Chernobyl and Fukushima live long in the memory. 

More recently, fighting around the Zaporizhzhia nuclear plant in Ukraine terrified observers who feared a stray rocket could lead to another nuclear meltdown. 

Nuclear physicist David Krofcheck from the University of Auckland does a full-on facepalm when asked about the fighting in Ukraine. 

"My message to my Ukrainian and Russian friends: please do not shoot at the nuclear reactors."

But Krofcheck says the fears many people have about the threat nuclear power poses is not always in line with the reality in 2022.

"There still is the need to be wary...but I think of all the energy that's been generated and the spinoff diagnostics, energy generation...I think that's probably closer to the truth than the rightfully shocking, scary events we've seen with nuclear power plants in Fukushima and Chernobyl. 

"I think those were the aberrations, not the norm, and I think a lot of people may not want to hear that, but that's my observation."

Krofcheck says nuclear power is produced when a heavy nucleus, like uranium, is encouraged to split into two lighter pieces, releasing a whole lot of energy.

That energy heats up water, which then boils and creates steam, which turns a turbine, which makes power.

"Nuclear power is just an incredibly sophisticated way to boil water," Krofcheck says. 

Of course, accidents at nuclear facilities can be devastating: the Chernobyl accident rendered more than 2500 square kilometres of land uninhabitable, and may be contributing to the premature deaths of thousands of people.

Yet proponents of nuclear power may viably point out that hundreds of thousands of people die every year from complications stemming from air pollution caused by burning fossil fuels. 

"The two cases we're talking about...you build a Soviet Union-style reactor, which has since been completely taken offline or massively remodelled...and you've got to be careful where you locate them. Maybe it's not so good to build a nuclear power plant in an earthquake zone.

"I think that is the trade-off for a stable base of energy...that societies want to have."

Krofcheck says nuclear power probably isn't going to be necessary in New Zealand in the short-term future: we have many methods of producing renewable electricity, from hydro to wind to solar, as well as significant geothermal reserves.

And nuclear power plants don't come cheap: you need to invest billions of dollars, and you need to have a real need for baseline generation to make a large-scale plant viable. 

There is also the issue of public sentiment: New Zealand's nuclear-free stance lives long in the memory, and in a sense forms part of our national identity and independence on the world stage.

Krofcheck says that may change in the future, as nuclear reactors get smaller and we develop more sophisticated ways of dealing with nuclear waste, which is currently stored in barrels which are kept on-site. 

But he says humanity cannot view nuclear power as a be-all and end-all: it's a bridge, he says, between the age of fossil fuels, and the energy utopia of renewables, which should be the ultimate goal.

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