As Adelaide gardens (and residents…) wilt in the first full-blown heat wave of the summer, here is a timely post from John Newlands to kick of the Decarbonise SA Summer Edition. In this post, John makes the case for a Small Modular Reactor (SMR) led development of nuclear in South Australia, beginning in Ceduna. As you will read, John has an eye on the limits SA is likely to be facing in water, and also gas and coal. It’s refreshing to read from someone who realises nuclear power has the potential to improve, not diminish, our water security.
Should I be concerned that I feel John’s post presents more convincing forward thought about the industrial and ecological future of our state and nation that I have heard from any politicians in quite some time?
The case for an SMR based energy park at Ceduna.
Some believe the world is influenced by ‘ley lines’ that bring together natural forces and indeed are used as a navigation aid by intergalactic visitors. In a similar vein I’d argue that Ceduna on the Great Australian Bight perhaps inevitably will become a point of convergence of several key material and energy flows with their associated political undercurrents. Currently or potentially these are
– energy and water supply for mining uranium and other minerals
– salinity tolerant desalination and reduced water extraction elsewhere
– possible developments in uranium enrichment, thorium and 4th generation nuclear
– reduced NIMBYism and political interference
– possible unification of the east Australian and WA grids
– staged but forward looking development
– new industry and jobs for SA.
The trigger for this thinking is what seems like the current roadblocks to the expansion of the Olympic Dam mine, the world’s biggest uranium deposit but primarily a source of copper, gold and silver. According to those specs the mine needs 650 MW of electrical power supply and a desalination plant on the coast that will produce 280 megalitres of fresh water a day, mainly pumped to the mine. The roadblocks are that the South Australian grid cannot readily supply that power and there is vehement opposition to the preferred near-landlocked site of the desal plant at Whyalla in upper Spencer Gulf. The narrow vertex of the gulf has elevated salinity and weak currents so the brine discharge would depend on tidal flushing for dispersal. It also the world’s only known mass spawning ground for the giant cuttlefish.
SA as a whole is facing declining coal and gas supply. It is not clear how the extensive windpower which the State prides itself will fare when the gas situation worsens. Possibly Federal intervention would be needed to guarantee gas supply from Queensland as southern gas fields deplete. Meanwhile other energy hungry developments are in progress. These include rare earths and thorium extraction also at Whyalla, using ore railed from the NT. Another major development is zircon sand mining closer towards the WA border and this time coincidentally nearer the site of the Maralinga A-bomb tests in the 1950s. Those sands contain some thorium bearing monazite and will be shipped from Ceduna to Geraldton in WA for separation. The sands are mildly radioactive (not due to bomb tests) and will use the same loading facilities as wheat and gypsum. Apart from mineral sands the region has other prospective mines for copper gold, uranium and iron ore; all these new mines will need electricity and water supply.
In my opinion the desal should be on open coastline rather than the stagnant waters of upper Spencer Gulf. If you swing a 350 km radius from Olympic Dam the obvious alternative site is Ceduna. Even if SA could somehow acquire a new centralised power source and adequate transmission the desal could still be at Ceduna using all-electrical reverse osmosis. However my alternative proposal is this… go for broke on a west coast desal and generate all the needed power at Ceduna. This would not only replace the Artesian Basin water used by OD but also the water pumped 400 km from the River Murray to the east. That pipe carries up to 66 GL a year (180 ML/d) and pumps water via Pt Augusta to western towns, not quite to Ceduna but for example to Woomera only 70km from Olympic Dam. Note it is already proposed to augment some of that river water with the desal intended for Whyalla. A sufficiently big desal (say 400 ML/d) could replace all of the river water as well as the groundwater used by OD. Then there’s new mines and factories in the future. Based on the 400 ML/d Wonthaggi Vic desal that might consume up to 100 MWe of power if done by reverse osmosis with no thermal input. However there will be a power saving on the pumps on the River Murray far to the east which could be retired to standby mode.
Thus the combined generating facility and desal at Ceduna would send both power and water directly to the mine. But what source of power? In my opinion it would be politically prudent to use small modular reactors perhaps optimised for desalination through a thermal assist or load switching. I defer to the wisdom of others on the specifics. The SMRs together producing 650 MW or more would be seawater cooled. While the electrical supply to OD would be initially private the additional regional water supply would be a public service. If that plant was Australia’s first commercial reactor it would ‘break the ice’ for nuclear in other parts of Australia. More importantly if it could be up and running trouble free within a few years it should get favourable media treatment. Once the site is bedded in I think there is every reason it could scale up to later gigawatt scale generation and a range of support industries.
There are good reasons for expanding Ceduna if the money can be found. In the long run some have called for an HVDC cable across the Nullarbor to join the east Australian grid (Ceduna being its westernmost point) to WA at Norseman. Logically the eastern end would be at Pt Augusta for which the transcontinental railway line provides a natural easement. That would be intersected by the power and water line from Ceduna to OD at which point an electrical node could be created. I suggest building the private grid first then think about the public grid later. An east-west electrical link might solve the peaking power problem if as predicted south eastern Australia’s gas situation becomes dire. Rather than pump physical gas the peaking power could come as electrons from WA through the cable. Even just with links to the east some have called for improved transmission to take advantage of untapped windpower potential. Whether that makes economic sense or not it does at least buy some support from renewables enthusiasts.
Later the Ceduna energy park site could consider uranium enrichment advocated by some. That means we could home fuel 3rd generation plant like the AP1000 rather than import processed fuel. Interestingly Ceduna will also have thorium coming from all angles, from the monazite sand to the west, the Whyalla rare earths plant to the east and even the OD tailings to the north contain thorium, currently discarded. After an SMR beginning we could later on consider some form of large scale 3rd generation NP that can use thorium such as the CANDU. Or perhaps skip large scale 3rd generation and go straight to 4th generation technology like the IFR. If the choice means metallic thorium then that can be a new industry along with fuel reprocessing.
Thus the sequence for the Ceduna site could be
Step 1 – SMR and desal with direct line to Olympic Dam
Step 2 – augment the larger water network
Step 3 – grid upgrade to the east, possibly to the west
Step 4 – consider U and Th enhancements
Step 5 – consider large Gen 3 and/or Gen 4
In the rough map I’ve shown the approximate position of the rail line and the corridor to the coast but to avoid clutter I’ve omitted the current water and transmission lines.
I’ve also avoided any discussion of the money side of things but I note the following caveats. Let us suppose none of this happens and we then ask how much have we saved. If the OD expansion uses a new gas fired power plant and gas becomes prohibitive that will be a costly mistake. Suppose they go ahead with the Spencer Gulf desal and the marine life suffers, a PR disaster. Another big mistake. Suppose they wait to build the first NP closer to Adelaide but protests and political interference turn the project into a nightmare lasting a decade or more. That could be the biggest mistake of all. It could work out quicker and cheaper to start small under compelling circumstances then build up.