Nuclear is a natural with wind and solar

(published in The Australian Feb19/21)

Australia’s ability to reach net-zero carbon dioxide emissions by 2050 will be determined, according to Scott Morrison, by advances in science and technology. It is impossible not to agree with his assessment.

While there is no utopian solution to our energy challenge, all sources of low-emissions energy, be it wind, solar, hydro or nuclear have their strengths and weaknesses.

Rather than treating these energy sources as being part of some sort of competition, an obvious pathway to zero emissions is to do as suggested by Canadian Natural Resources Deputy Minister Jean-Francois Tremblay – to seek ways to get them to work together “to achieve climate neutrality.”

Canada, like most advanced economies, has a mix of energy sources, with hydro the biggest contributor (60 per cent) followed by nuclear (15 per cent), coal (7 per cent), gas/oil/others (11 per cent) and non-hydro renewables (7 per cent).

“We can look at nuclear as a baseload on which we can build our alternate strategy,” Tremblay said. “I think that’s a fundamental shift that is now allowing us to be pragmatic.”

The shift is aided by the advances being made to small modular reactors designed for serial construction, a game changer that could benefit Australia.

But, astonishing though it is, Australia has legislation passed in the 1990s prohibiting nuclear power, while the country is the third biggest uranium exporter, selling uranium oxide to a dozen or more countries, mostly the US, the EU, Japan and China.

If we are to confront the challenge of climate change, the overriding objective should be to develop emission-free energy sources.

With its reliable baseload, emission-free nuclear is a natural to form a symbiotic alliance with less reliable renewables such as wind and solar. All are carbon-free sources and the pathway to climate change amelioration.

Indeed the Intergovernmental Panel on Climate Change states unequivocally that without the contribution of nuclear power it would not be possible to keep future temperature rises below its 1.5C target.

And there is another alliance for nuclear waiting in the wings. Hydrogen – named after the Greek for “water maker”, indicating its benign nature – is in the early phase of development on the energy stage as a star performer.

The World Nuclear Association estimates that the energy demand for hydrogen production could exceed today’s electricity generation, and “it has some potential to replace oil as a transport fuel.”

While in much of the world transport is expected to be the largest hydrogen user, heating for buildings will run second, potentially replacing natural gas.

Like electricity, hydrogen is not a primary energy source but an energy carrier. As it does not occur in free form it must be separated from molecules such a water (H2O) or methane gas (CH4). The obvious source of hydrogen is the most plentiful compound on the planet – water- thus allowing for zero-carbon hydrogen via electrolysis. Not surprisingly, energy is needed for this. Any source will do but it would seem sensible to employ a carbon-free type.

Hydro is one of these and Tasmania is looking to develop its advanced manufacturing zone in the state’s north using hydro. Elsewhere in Australia, where hydro contributes only about 6 per cent of energy to the national grid, the only other clean source with the advantage of consistency and flexibility is nuclear.

Wind and solar suffer from debilitating intermittency when the wind doesn’t blow and the sun doesn’t shine. A steady energy source is required to fill the downtime. In Australia it is usually coal or natural gas-fired plants.

The IPCC points out that nuclear power is a non-intermittent energy source (other than hydro) that emits the least CO2. It can come to the rescue of renewables. An advantage is its ability to adjust its power output as demand for electricity fluctuates throughout the day and night, a feature known as load-following.

In the near future, small modular reactors could provide the base power needed to keep the hydrogen production steady. Defined as less than 300 megawatts, and capable of being as small as 5MW (called microreactors), these devices aretransportable on trucks to where the need requires.

Australia is showing increasing interest in the potential of hydrogen. The National Hydrogen Roadmap produced by the CSIRO mentions the exciting opportunity of developing a new export capability based on liquid hydrogen, which it says could be a potential “game changer for the local industry”.

In the future, as the transition in the energy system gains pace and fossil fuels reduce their contribution to Australian exports, liquid hydrogen could enter the gap.

If we take seriously the need to achieve net-zero carbon emissions, it makes sense to invite emission-free nuclear into an alliance with renewables to inject some certainty into the exercise. In fact, it is hard to see Australia achieving the Prime Minister’s goal without it. What are we waiting for?

————————————————————————————————————————–Tony Grey was the founder and chief executive of Pancontinental Mining Ltd., which discovered the Jabiluka uranium orebody. He was also chairman of the Uranium Institute, (now known as the World Nuclear Association).