They site the nuclear plants adjacent to the ocean for access to large amounts of cooling water. If they ever built them in Australia they would almost certainly do the same thing. Of course in an emergency they do what the have to do and there is no possibility of having a discussion about the possible harmful effects of dumping all that water in the ocean. Could it possibly contain harmful radioactive material?
Even in normal operation all that waste heat being dissipated in the ocean must affect water temperatures for some distance around the plant (plants?). This is probably considered as an unavoidable but acceptable consequence but I wonder if there is any research into the state of the ocean near coastal nuclear plants as a result of 1) radiation and 2) warming?
It is interesting to review this following from the Australia Institute 2007 research paper [b]Siting Nuclear Power Plants in Australia – Where would they go? [/b]
[i]Nuclear reactors operate by using heat from a nuclear reaction to create steam which then drives turbines to produce electricity. The water requirements to drive the turbines are relatively small because the steam cycle is a closed loop. However nuclear reactors generally require large volumes of water for cooling purposes. The amount of water required for cooling purposes depends on the technology that is employed. There are four main types of cooling systems: evaporative cooling; once-through seawater cooling; once-through freshwater cooling; and dry cooling (Rose 2006).
Coal-fired power stations in Australia generally use evaporative cooling. As the name suggests in evaporative cooling systems the waste heat is discharged into the atmosphere through the evaporation of water. These systems require large volumes of water.
According to a report prepared by Dr Ian Rose for the Queensland Government evaporatively-cooled large coal-fired power plants use around 1.85 – 2 litres of water per kilowatt hour (L/kWh) (Rose 2006). By comparison evaporatively-cooled nuclear power plants use around 25 per cent more water or around 2.3 L/kWh. This suggests that a 1000 MW nuclear power plant generating 8000 GWh annually would require roughly 20 gigalitres (GL) of water each year(equivalent to almost 9000 Olympic swimming pools).
Rose argues that the preferred option for nuclear power stations would be ‘one based on evaporative cooling from a reliable fresh water source’ (Rose 2006 p. 4). However due to the current condition of Australia’s freshwater resources it seems more likely that nuclear power plants would use seawater for cooling purposes. This could involve the use of seawater for evaporative-cooling purposes or once-through cooling.
Once-through cooling systems are cheaper than evaporative cooling systems to construct. However they require large volumes of water and the temperature of the water that passes through the power plant is raised by several degrees giving rise to thermal pollution problems. In Australia once-through freshwater cooling is unlikely due to the current pressure on water resources. Once-through seawater cooling is likely to be preferred due to the availability of seawater and the fact that the hot discharge water would be diluted in the ocean thereby potentially reducing environmental impacts. [/i]
[url=https://www.tai.org.au/file.php?file=web_papers/WP96.pdf]The full available document here[/url].