Nuclear power explained in 12 numbers to help you understand how it fits Australia’s energy needs

0 grams — The amount of carbon dioxide nuclear power plants emit generating electricity.

There are, according to Australia’s former chief scientist Alan Finkel, four kinds of large-scale power generation that directly emit no greenhouse gas emissions.

Three of them are obvious and fit firmly in the renewable category – hydro-electricity, wind and solar power.  

The fourth is nuclear power, which produces no greenhouse gases during operation, but requires fuel in the form of radioactive elements to power it. 

Like renewable energy, the only emissions come from any fossil fuels used in the mining, manufacturing and operation of the plants and fuel. 

Even over the life cycle of a plant, nuclear generates just 13 grams of carbon equivalent-emissions a kilowatt hour. That’s equivalent to wind power and lower even than solar power at 43g CO2/kWh. 

Notably, it’s just a fraction of the life-cycle emissions associated with coal, which generates 1050g CO2/kWh, and gas, which produces 450g CO2/kWh.

Nuclear reactors are effectively giant kettles, boiling water through the process of splitting uranium atoms and using the steam generated to drive a turbine. 

According to Dr Finkel, nuclear power is an ideal fit for electricity generation in many ways. 

Firstly, it’s what’s known as a synchronous generator, meaning it produces power at a rate that matches the “heartbeat” of the alternating current electricity system. 

Nuclear plants helped “strengthen the system” through characteristics such as inertia – the physical property that makes it easier to balance a moving bike rather than a stationary one.

Dr Finkel also said nuclear was “dispatchable”, meaning it can provide power on demand for days, weeks and months at time. This is something it shares with coal-fired power, but nuclear has a far smaller mining footprint. 

For example, he said, “a coal-fired station used approximately 100,000 tonnes of coal to produce the same power as 1 tonne of uranium in a nuclear power station”. 

“From a pure engineering point of view, nuclear power is very, very attractive,” Dr Finkel said. 

1.5 billion tonnes — The volume of greenhouse gas emissions nuclear power helps to avoid each year globally.

It’s almost 70 years since the world’s first commercial nuclear power station opened at Calder Hall in Cumbria in north-west England.

Since that time, according to the International Energy Agency (IEA), “the use of nuclear reactors has reduced carbon emissions by over 60 billion tonnes”. 

That’s an amount equivalent to almost two years’ worth of energy-related emissions across the entire globe. 

Over the course of a typical year, nuclear helps avoid about 1.5 billion tonnes of greenhouse gases – more than three times Australia’s annual emissions. 

And despite the rapid growth of wind and solar power, nuclear and hydro still account for more than half of fossil fuel-free electricity generated around the world. 

“Achieving the pace of CO2 emissions reductions in line with the Paris Agreement is already a huge challenge,” the IEA said in 2019. 

“It requires large increases in efficiency and renewables investment, as well as an increase in nuclear power.” 

However in an interview with the Australian Financial Review, the head of the IEA Fatih Birol, said nuclear power was not a good option for Australia as it would take too long.

“I have been a proponent of nuclear for many years,” he said. 

“But if there is a country that has a lot of resources from other sources, such as solar and wind, I wouldn’t see nuclear as a priority option. I’m talking about Australia now.”

9 per cent — The share of the world’s electricity sourced from nuclear power.

Nuclear comprised just over 9 per cent of the world’s electricity generation in 2023. 

There are about 440 reactors internationally, according to the World Nuclear Association, while a further 61 are under construction. 

Most of those are being built in countries like China and India, where big populations and huge growth in electricity demand have spurred investment in all types of generation. 

Australia, for the record, has no nuclear power industry. 

But from a high of 17.5 per cent in 1996, the share of global electricity demand supplied by nuclear has fallen to barely half that now. 

While much of the decrease is relative – that is, rising demand for electricity has been met by other sources including gas-fired and renewable power – the fact remains nuclear output has been flat. 

Wind and solar, while starting from a low base, are growing faster than any other power source in history, as they undercut the profit margins of fossil fuels. 

Australia would need to partner with another country to build a nuclear power plant, but turning to the current leaders in the space, Russia and China, wouldn’t be an option.

John Quiggin is a senior fellow in economics at the University of Queensland.

He said Australia – for obvious geopolitical reasons – would be unlikely to hitch its wagon to either country. 

“I don’t think that requires a lot of imagination,” Professor Quiggin said. 

“If Chinese firms have any special sauce, that’s no use to us. I would say the Chinese model is essentially not relevant.” 

As you can see from the chart above, new nuclear energy is barely keeping pace with closures, and outside of China there is no evidence of a jump in the amount of nuclear energy coming online. 

In another sign of where the world is going, 2023 was the year when global large-scale battery investment overtook nuclear investment for the first time. 

1.5 times — At least how much more expensive building nuclear power in Australia would be than renewables supported by batteries.

One of the reasons the Coalition is proposing nuclear is around the cost of the clean energy transition, but when the CSIRO looked at the figures it found that it is a significantly more expensive option.

Building renewable energy on its own is a fraction of the cost of new nuclear, and in some cases lower than the cost of actually running nuclear power stations.

However, a better comparison is between nuclear and solar or wind supported by storage and transmission.

The CSIRO looked at this in its latest GenCost report, which compares the cost of different ways of producing electricity, and found it was at least 50 per cent more expensive than large-scale wind and solar power backed by “firming” technologies such as batteries.

“We did a lot of work to determine what nuclear power would cost in Australia,” Paul Graham, the chief economist of the CSIRO’s energy business unit, said.

“We’ve previously reported on small modular reactors.

“But this time, we did an update and looked at the cost of large-scale nuclear reactors, and they’re cheaper — on the order of $150 to $250 a megawatt hour.

“That’s still one and a half to two times the cost of renewables.

While this figure shows it is clearly cheaper to build renewables with batteries, digging into the modelling only makes the case worse for nuclear.

When looking at the cost of renewables, the CSIRO factored in the maximum possible figures for grid upgrades, higher than the expected cost.

It also warned that the nuclear cost could only be achieved by building nuclear power at scale, so multiple reactors one after the other. The first power plant would be subject to what’s called a “first of its kind” multiplier, which could double the price from $8.5 billion to $17 billion.

Nuclear isn’t alone in facing this cost, it’s applied to any technology a country hasn’t built before, and we only have to look at the NBN or Snowy 2.0 to see the likely outcome.

But even in the world of big projects, nuclear power stations have among the worst track records for running over time and over cost.

Mega project expert Bent Flyvbjerg has gathered a database of the costs and time-frames for major projects around the world.

It shows nuclear power plants are among the worst for cost and time-frame overruns – on average they come in at more than double the original quoted price. 

Taking this conservative approach means the CSIRO’s figures are far more generous to nuclear than international comparisons.

Global investment bank Lazard has been publishing an analysis of what’s called the levelized cost of energy (LCOE) since 2008. LCOE is essentially how much money a power source would have to sell its electricity for to make any money.

In 2023, the lowest LCOE for nuclear power was $220 a megawatt hour, compared with onshore wind and batteries, which was $65MW/h, more than three times the cost. Even the top estimate of its range for solar and wind was still below nuclear’s cheapest range. 

In the 11 years the CSIRO says it would take Australia to get ready to even start building a plant, the economics of nuclear are expected to get even worse.

Prices for renewable energy and batteries have been dropping precipitously as they’re deployed at a greater scale. Nuclear costs, meanwhile, have been rising since 2009.

$88 billion — The latest projected cost of building the 3.2 gigawatt Hinkley C nuclear plant in the UK.

Unlike renewable energy produced at volume, getting an accurate price on nuclear power is tricky. But looking at projects underway indicates it can be a very expensive proposition. 

A big part of the relative decline in nuclear power has been its high cost compared with many of the other technologies vying for political, investor, and social support. 

Exhibit A in this tale is the Hinkley C plant on the Somerset coast of the UK. 

In 2007, the then chief executive of French power provider EDF, which wanted to build the plant, boasted that by 2017 Britons would be able to cook their Christmas turkeys using electricity from Hinkley. 

When EDF finally committed to the giant 3.2 gigawatt plant in 2015, the initial budget was £18 billion ($34 billion), with a scheduled completion date of 2025. 

Earlier this year, following a spate of cost and time blowouts, EDF said the estimated costs of building the plant would soar to as much as £46 billion ($88 billion). 

Completion of the first reactor was not expected until 2029 at the earliest. 

The French utility, meanwhile, did not even bother to give a time-frame for the second reactor. 

What we do know is how much the British public will be paying for power from Hinkley. In order to build the plant the UK government committed to paying $171/MWh for the first 35 years, adjusted to inflation. This means the prices rise in line with inflation, by the end of 2023 it was $245/MWh.  

For context, Australia’s wholesale energy cost in the last quarter of 2023 was $48/MWh.

Dr Finkel described Hinkley’s costs as “stunningly expensive”. 

But he said that even taking a more favourable recent example from a Western country – the expansion of the Vogtle nuclear plant in the US – was not a great advertisement for the industry. 

“Those third and fourth units were proposed in 2009, approved a few years later, and began commercial operation in 2023,” he said. 

“That’s 14 years from when they were proposed, call it 11 years from when they were approved. So quite slow.” 

Dr Finkel said Hinkley offered a way to compare the cost of large-scale nuclear to renewable sources supported by batteries. 

To be able to provide one gigawatt of power 60 per cent of the time, a wind farm would need a 2GW farm and 7.2GW in batteries – under today’s figures that would cost about $7 billion.  

Currently, the cost of the Hinkley plant is $27 billion a gigawatt, while the US Vogtle 3 is $21 billion a gigawatt of capacity. 

There are currently 21 gigawatts of coal-fired power in the Australian grid. 

10 years — How long we have to replace 90 per cent of Australia’s coal-fired power.

One of the complaints levelled at nuclear power is that it isn’t a quick solution, but why does this matter? 

There are two reasons why Australia needs to act now. One is the need to reduce greenhouse gas emissions in line with the country’s international commitments.

But, secondly, we urgently need a replacement for our aging fleet of coal-fired power stations, which currently supply over half of our electricity.

In its latest plan, the Australian Energy Market Operator (AEMO) predicted 90 per cent of coal power would be gone from the grid within 10 years, and the final power station would be shut by 2038, just 14 years away. 

The chart below shows how quickly coal capacity is likely to drop out of the system. This change isn’t being driven solely by environmental concerns. The economics of building a new coal power plant, and increasingly running one, don’t stack up.

The government does not decide when power plants are closed, instead, power plant operators have to give three years’ notice before closing.

Operators run the plants to make money, and if they can no longer make a profit, the burden falls on taxpayers to subsidise them, driving up electricity costs.

To give you an idea of the sorts of costs involved, AGL is spending $760 million this financial year on maintaining and upgrading its two remaining coal-fired power plants. 

The New South Wales government has just agreed to pay Origin up to $250 million a year to keep its Eraring power station open for an extra two years. The longer we take to replace this power, the greater the risks to the taxpayer.

13 years — How long it took the United Arab Emirates to first connect a nuclear reactor to its energy grid.

With that time frame in mind let’s look at a best-case scenario for starting from scratch. 

The only country in the world that has managed to successfully build nuclear from scratch in the last 30 years is the United Arab Emirates (UAE).

At Barakah in the oil-rich emirate of Abu Dhabi, the UAE developed a nuclear plant that will soon generate up to 25 per cent of the country’s electricity needs. 

From the time the UAE decided to develop a nuclear power program, it took 13 years to deliver the first of four reactors. 

The cost, in 2018, was stated to be $US24 billion ($36 billion). 

Professor Quiggin said the UAE was a modern exemplar of the nuclear power industry. 

But he says it would be a mistake for Australia to think that following suit would be easy, or even achievable in the first place. 

“The most comparable instance, really, in some ways, is the United Arab Emirates, who’ve started from scratch as we would be,” Professor Quiggin said.

“But they, of course, have a bunch of advantages that we don’t have, starting with the absence of any kind of democratic rights for people, which means they can just go ahead and do stuff without worrying too much. 

“I mean, everything’s kind of opaque. But the high number I’ve seen – and the high number is usually the right one – is $US30 billion. That’s $50 billion Australian.

“But of course, they had low-paid workers, there’s been a fair bit of inflation since they started … and they have a lot of advantages in siting because they can just plonk the thing in the desert, on the coast somewhere they didn’t have to worry about, for example, emergency planning zones, and so forth. 

“So, I think it’s highly unlikely we could get much below $100 billion for a four-reactor program.” 

Korea’s state-owned power company, which built the first reactor in the UAE, has never released costings of the project. 

As a democracy, said Professor Quiggin, Australia would face a much longer process not just to legalise nuclear power, but to legislate details of its use and storage.

And the UAE is the exception, not the rule. While the World Nuclear Association claims there are 30 emergent countries exploring nuclear, the reality is much less impressive.

Just three other countries have managed to reach the stage of actually starting to building nuclear power plants — Turkey, Egypt and Bangladesh.

Turkey, which took decades to reach the point of starting construction on plants, still has no nuclear power.

Bangladesh, which is heavily reliant on imported fuel, made the decision to commit to nuclear power in the early 2000s. Construction of a plant by Russia’s nuclear agency started in 2017 and still is not complete. 

Egypt carried out a feasibility study for a nuclear power plant in 1999, issued a tender in 2014, and construction only started in 2022.

According to the World Nuclear Association, there are no other emerging countries that have plants planned, which it defines as “approvals, funding or commitment in place, mostly expected to be in operation within the next 15 years”.

There are only six countries with plants proposed with “timing very uncertain”, and the industry itself doesn’t expect that to change.

“Despite the large number of these emerging countries, they are not expected to contribute very much to the expansion of nuclear capacity in the foreseeable future – the main growth will come in countries where the technology is already well established,” the World Nuclear Association says. 

20 years — How long Alan Finkel says going to nuclear will delay the shift from fossil fuels.

Dr Finkel is not opposed to nuclear power as an energy source, but said it cannot be thought of as a solution to decarbonising our power system for the next few decades. 

He said a call to go direct from coal to nuclear is effectively a call to delay decarbonisation of our electricity system by 20 years. 

“In Australia, we’re the only country amongst the G20 that has a legislated ban against nuclear power. And that was brought in by the Howard government, back in 1998,” Dr Finkel said.

“So the first step would be to reverse that ban. And depending on how the political winds blow, maybe that will happen.”

There are also state bans that would have to be overturned, and Australian premiers and opposition leaders have either rejected or declined to support the Coalition’s plan. 

Dr Finkel said reversing any ban is still only the first step, and the process of legislating and planning for nuclear power is lengthy and complicated. 

“Once the ban is reversed, you can start looking at actually rolling out the nuclear power plants. There’s a lot to be done,” he said.

“The regulatory system needs to be looked at. We have a nuclear regulator, but they’re not set up for power generation, they’re more set up for medical, nuclear diagnostics. 

“You’d have to find the site and put out a bid process and find the first operator, authorise construction contracts, we would have to establish a waste management system. 

“It’s doable, but it takes time. You’ve got to anticipate that one day 60 years later, the reactor site will have to be decommissioned. You’ve got to think about that up-front and put aside the money and the rules. 

“Then, of course, there would be a huge quantity of environmental requirements and safety requirements that would have to be met, new workforce to be trained.

“There will be protests. And so you’d have to deal with the conventional protests, and then the legal opposition that will go I would guess, perhaps all the way to the High Court. 

“And then you’ve got to start the construction and commissioning. So that’s a lot to do.”

Dr Finkel said smaller nuclear technology, which is yet to be developed, may be a good solution for Australia down the track, but to build out a fleet of nuclear power stations would take 40 to 50 years.  

“I can’t imagine us starting one until, as I said, the mid-2030s, which means realistically, we wouldn’t have anything till the early 2040s,” he said.

“Now, that doesn’t mean it’s too late. It’s too late for decarbonising. 

“We are obliged – we must decarbonise our electricity system. So we can’t say let’s hold everything up and wait for nuclear that would add a minimum of 20 years. 

“And it’s not as if when we get the first small modular reactor that within a year or two, we’ll have small modular reactors for all our electricity. 

“It would still take another 20 or 30 years to roll out the 40, 50 or 60 gigawatts that we would need.” 

96 per cent — How much of our grid is projected to run on renewables and storage by 2040.

Dr Finkel noted their inherently variable nature meant wind and solar would be unlikely to meet all of Australia’s electricity needs without support from other technologies. 

He said finding the right back-up – or back-ups – was therefore essential. 

While batteries would inevitably be a big part of the equation, he said they, too, had limitations in that they could not run on demand for days or weeks at a time, as may sometimes be needed.

It was in this space, he suggested, that nuclear power could, for the right price, possibly play a part, acting as a controllable and reliable safety net for an electricity system that produced no emissions. 

Even then, this role would be likely to represent a small fraction of Australia’s energy needs – AEMO estimates by 2040 about 96 per cent of the country’s power will come from renewable energy and storage. 

And there are a range of technologies, from green hydrogen to geothermal that will be competing for this tiny slice of our energy market. 

In terms of what keeps energy experts up at night, how to replace the small amount of gas still in the system 20 years down the track, pales in comparison to the challenges of rebuilding the grid around renewable energy over the next decade. 

10,000 years —  How long the US EPA requires the isolation of nuclear waste.

It’s impossible to talk about nuclear energy without mentioning safety considerations. By one measure – how many people die per unit of electricity generated – it’s remarkably safe. 

But that figure really refers to how many people have died so far, because the nature of nuclear fuel is that the waste remains radioactive and dangerous for an almost inconceivable amount of time. 

The US Environmental Protection Agency (EPA) set the requirements for isolation of nuclear at 10,000 years, but that’s just a tiny fraction of how long waste remains dangerous, in some cases up to 1 million years. 

Sweden, which generates approximately 30 per cent of its power from nuclear energy, is building a facility to keep waste isolated for 100,000 to 1 million years. So far it has spent $9 billion on building the long-term storage solution, drilling 500 metres deep into stable rock beneath the earth’s surface.

Completing the job is budgeted to cost another $16 billion.

Until this facility is finished, Sweden’s ability to use its nuclear plants has been affected by the limits of its interim storage. 

Given these sorts of problems, nuclear storage ranks as the worst for cost and time overruns, according to mega project analyst Professor Flyvbjerg.

In 2012, Australian legislation was passed for a national radioactive waste management facility to hold the small amounts of material we generate from things like research and medical waste.

Twelve years on, the process of finding a site is essentially starting again after a court ruled out a South Australian location. 

There is another cost to keep in mind for nuclear power, and that’s the cost of disasters. While they have been rare, the cost of the Fukushima disaster alone shows the potential scale of these events.

The Japanese government in 2016 costed it at $311 billion, $115 billion of which was just for cleaning up the power plant and said it would take 30 to 40 years. More recently, the Japan Center for Economic Research said that cost could increase to as much as $800 billion. 

These risks can be managed, but the question again comes back to how long it will take, and what it will cost. 

0 — The number of commercial small modular reactors under construction or in operation outside of China and Russia.

So if nuclear power plants are too big to work well for our grid, and take too long to build, isn’t there a way to use the technology in a smaller form?

The enormous costs and times required to build traditional large-scale nuclear plants have led many investors to shun the industry. 

But it’s also fuelled interest in an alternative – one that would supposedly be cheaper, easier and quicker to develop, and it’s something the Coalition has championed.

This alternative can loosely be described as the small modular reactor.

Professor Quiggin said the concept was simple enough, and it was in the name, too.

“Modular implies the things are built in a factory and shipped to the site,” he said. 

In theory, he said modular reactors would be able to overcome the disadvantages of their small size by capitalising on the benefits of mass-production and their cheaper up-front cost.

No longer would electricity utilities need to build massive conventional nuclear plants that were each individually designed and constructed.

They would instead be able to buy a small reactor effectively off a shelf, plonk it at a site and bolt on extra modules as they might be needed.

And certainly, some major investors are keen. 

Among those putting their money behind the technology is Bill Gates, the world’s seventh richest person. 

The problem is no one outside of Russia and China has managed to actually build a commercial reactor.

The Western world’s most advanced SMR project, a venture headed by US firm NuScale, collapsed in December.

NuScale had been the flag-bearer of the technology, signing provisional agreements with utilities that would have ultimately been its customers.

In 2016, the project had an original target of selling power at $US55 a megawatt hour ($83/MWh).

Last year, NuScale conceded the costs had jumped to $US89/MWh, even with subsidies, though some analysts said they were likely to be far higher still. 

In the end, according to NuScale, the project collapsed because of a lack of people wanting to buy power from a plant that was going to cost $US9.3 billion ($14.3 billion). 

Officially, NuScale blamed rising construction costs and delays for the way the project had spiralled out of control. 

But Professor Quiggin said it was symptomatic of an industry that was unable to deliver projects on time or on budget.

He said that in order for SMRs to work, their developers had to make some major technological breakthroughs to compete on price.

Put simply, Professor Quiggin said NuScale and every other developer had so far failed to do so.

And this, he said, was the rub because the clock was ticking on efforts to decarbonise electricity systems. 

“I mean … at some point in the future somebody might come up with a technology that works,” he said.

“But there’s no reason to think that and even if it does happen, it’s now long after the timescale that could possibly be relevant for Australia.”

In the meantime, costs for renewable energy are getting even lower. 

3.9 times — How much more a small modular reactor would cost compared to wind and solar supported by batteries.

Even if small reactors were to become viable, they still face the problem of the proven technologies of wind and solar supported by batteries or other forms of storage, which have been declining in costs beyond projections. 

The CSIRO used the cost of the NuScale project at the time it was shelved to work out what the levelized cost (LCOE) would be for a small reactor. 

According to the most recent GenCost report, an analysis of new electricity generators’ costs, the estimated “average” cost of an SMR would have been between $387-641/MWh in 2023, almost four times the cost of wind and solar supported by batteries.

It projected that costs would gradually decrease in coming years, but still amount to $230-382/MWh in 2030.

As noted above, the GenCost report found that wind and solar power were the cheapest options even when accounting for the storage and transmission costs needed to back them up.

America’s National Renewable Energy Laboratory came to a similar conclusion. 

It found in 2022 that onshore wind and solar could cost as little as $US30/MWh ($45/MWh).

At the same time, investment bank Goldman Sachs predicted battery prices would fall as much as 40 per cent by 2025 compared with 2022.

Dr Finkel said on a cost basis there was no comparison between renewable energy and nuclear power. 

To that extent, he said the rise and rise of wind and solar in Australia would march on until those two technologies dominated, supplying the vast majority of our power.