JOHN DWYER. How are we going to water the farm now that copious life sustaining rain is but a memory?Sep 8, 2018
The change in the world’s climate is currently on full display with equatorial deluges, hurricanes and typhoons causing destruction and misery while the the rest of the world burns and experiences record temperatures further North than ever recorded before. As a 78 year old Australian I am well aware of the frequency with which our framers have had to deal with droughts but the current drought that has stripped so much of the country of its fertility for more than six years, is extremely alarming when viewed in the context of the changes in global weather. While we must do all that is possible to stop further global warming it seems likely that we will, in a best case scenario, need to live with and manage the new status quo. While we appropriately support our farmers in this crisis surely we should be examining every possible strategy for improving the water supply to now chronically arid landscapes and indeed country towns that we need to rescue so they can help feed ourselves and the world. One suggested solution, explored here, would involve the use of nuclear power to desalinate huge volumes of seawater.
“Water, water everywhere and not a drop to drink” lamented the Ancient Marriner as he knew seawater could not quench his thirst. But we know how to remove the salt from seawater, the most abundant resource in the world. My previous contributions to P & I involved me sharing thoughts about subjects I know a lot about. Not so today. I have no personal experience or expertise to share on the topic of desalination but would hope to stimulate some discussion and provoke real experts to help us all understand whether a seemingly attractive and bold initiative ( the creation of strategically placed nuclear powered desalination plants) is technically and politically feasible in Australia.
As one does, in total ignorance of the subject matter, I went to Google and asked if any country was pursing this strategy. I did know of course, that many cities in Australia have invested in desalination. I well remember the genesis of our NSW plant in the days when our dams were nearly dry and water police patrolled the suburbs dishing out instant fines to criminals caught washing their cars. The plant has never been needed and costs a staggering $500,000 a day to keep operational but I am glad its there. It isn predicted that the dams Sydney relies on will be at 60% of capacity by November, a figure that would trigger the injection of desalinated water into our system. Full desalination capacity may not be available until the middle of 2019 however.
There are 19,000 desalination plants in the world and more and more are nuclear powered. Most efficient is the use of nuclear power plants that produce electricity but in low demand periods let their power loose on desalination. Turns out that desalination techniques require remarkably small amounts of electricity to be efficient and many small nuclear units are dedicated solely to desalination.
In 2015 the International Atomic Energy Agency (IAEA) noted:-
“Nuclear desalination is generally very cost-competitive with using fossil fuels. Only nuclear reactors are capable of delivering large-scale desalination projects”.
A World Economic Forum report in January 2015 argued that “shortage of fresh water may be the main global threat in the next decade. Fresh water is a major priority in sustainable development. Where it cannot be obtained from streams and aquifers, desalination of seawater, mineralised groundwater or urban waste water is required. 2.3 billion people live in water-stressed areas, 1.7 billion of them having access to less than 1000 m3 of potable water per year. With population growth, these figures will increase substantially”.
The feasibility of integrated nuclear desalination plants has been proven with over 150 reactor-years of experience, chiefly in Kazakhstan, India and Japan. Indicative costs are US$ 70-90 cents per cubic metre of desalinated water, much the same as fossil-fuelled plants in the same areas.In Australia, six major seawater plants were commissioned at a cost of A$ 12 billion between 2006 and 2012.
While the current scale of the demand for non-fossil fuel desalination demands nuclear power there is much research on the use of renewable energy ( wind and sun) to power desalination. Turns out we are major contributors to such efforts. There are two seawater desalination plants in Perth, a 45 Gigaliter (GL)/yr one (costing A$ 387 million) completed in 2006 powered by a wind farm, and a 100 GL/yr one powered by dedicated renewable energy, which together provide half the city’s needs. Following extensive trials, the city plans a groundwater replenishment scheme from treated wastewater which is expected to be half the cost and use half the energy of seawater desalination.
For agricultural demand we would need to pipe desalinated water over large distances. Its feasible, BHP Billiton and Rio Tinto have built a $3.43 billion, (79 GL/yr) seawater desalination plant with twin 1.07 m diameter pipes and pumps for their Escondida copper mine in the Atacama Desert. Seawater is pumped 170 km inland to a reservoir near the mine, 3200 m above sea level and 185 km inland! Compared to this piping water to selected rivers and agricultural hubs in Australia would be far less daunting. We know that oil and gas are pumped thousands of kilometres across Russian, European and North American wilderness areas. Is it not almost certain that the engineered distribution of water will become as indispensable as is the distribution of gas and oil today?
Russian company Rusatom sells dual power and desalination units. The company advertises that “We are paying great attention to expansion of our product range, including desalination facilities integrated with small modular reactor plants and floating nuclear power plants.” Although a relatively small plant, California’s Diablo Canyon seawater desalination plant is presently the largest operating desalination facility on the West Coast of America, producing about 675,000 gallons of freshwater a day.
The facility is not running at maximum capacity. It can actually produce a million and a half gallons of fresh water a day. After four consecutive years of drought, San Luis Obispo County sees the additional 825,000 gallons per day of freshwater production as key to helping it cope with the drought.
Diablo Canyon’s desalination facility will fall to second place in California when the commercial desalination plant in Carlsbad begins producing about 50 million gallons per day in November.The city of Marina Coast in Monterey Bay is planning to develop large desalination capabilities that would increase the state’s capacity to almost 100 million gallons per day.
This brings us to the lumbering very hard to move “elephant in the room”, namely our fear in Australia of the hazards that would be associated with our establishment of nuclear generated electricity. Risk/benefit ratios are constantly changing in our technology driven world. Its now safer to fly from Sydney to Melbourne than to make the journey by car. Casting a non-expert eye over the studies relevant to the question under discussion, there seems to be no doubt that the generation of electricity without using fossil fuels is a global imperative while the safety of using nuclear power for such generation is more than acceptable. Indeed over a 30 year period 22,000 fatalities were associated with the generation of electricity using coal while only 31 fatalities were associated with nuclear power generation.
Thirty three countries now use nuclear fission to generate electricity. 75% of France’s power comes from this source. The USA has the most plants which currently supply 20% of the countries electricity. The following analysis of the accidents that have have caused major concerns is provided by the World Nuclear Association which is dedicated to the promotion of nuclear power but the data does not appear to be controversial.
“In over 17,000 cumulative reactor-years of commercial operation in 33 countries, there have been only three major accidents to nuclear power plants – Three Mile Island, Chernobyl, and Fukushima – the second being of little relevance to reactor designs outside the old Soviet bloc.
- Three Mile Island (USA 1979) where the reactor was severely damaged but radiation was contained and there were no adverse health or environmental consequences
- Chernobyl (Ukraine 1986) where the destruction of the reactor by steam explosion and fire killed 31 people and had significant health (particularly Thyroid cancer) and environmental consequences. The death toll has since increased to about 56.
- Fukushima (Japan 2011) where three old reactors (together with a fourth) were written off after the effects of loss of cooling due to a huge tsunami were inadequately contained. There were no deaths or serious injuries due to radioactivity, though about 19,000 people were killed by the tsunami.
Apart from Chernobyl, no nuclear workers or members of the public have ever died as a result of exposure to radiation due to a commercial nuclear reactor incident. Most of the serious radiological injuries and deaths that occur each year (2-4 deaths and many more exposures above regulatory limits) are the result of large uncontrolled radiation sources, such as abandoned medical or industrial equipment”.
We have been so comfortable for so long with the status quo in Australia that we have not embraced bold infrastructure projects that fire the imagination, create thousands of jobs and improve our quality of life and its certainty. (We have talked for decades about super-fast trains but only talked) Such characteristics need to be brought to projects for improving our water distribution, we are after all the driest continent on Earth. Should we embrace nuclear power for desalination plants (and indeed electricity supply) we would build them away from our major cities to minimise the pumping distance for the water produced, a strategy that might ease the safety concerns of many. Better, of course if we can upscale renewable energy sources for desalination projects but for the foreseeable future our huge thirst demand our pursuit of the nuclear option. I do hope the current drought can see us engage in an evidence based debate to assess the merits and safety of the proposals herein. Our current approach seems to be centred on small (inadequate) cash handouts to farmers while we wait for the rain! Not good enough.
John Dwyer is an Emeritus Professor of Medicine and frequent commentator on the need for structural reforms to our health system. He has zero expertise in the subject matter presented above but like so many fellow Australians is very concerned about climate change and the implications of the drought now gripping so much of the country.