Retired Canberra CSIRO scientist JOHN L SMITH explains why the belief that wind, solar and renewables are going to be cheaper is flawed
POLLSTERS say that carbon emissions – climate change – is one of the most important issues in the coming Federal election. It seems that many voters want action without understanding the engineering issues.
For example, take the latest campaign commitment on electric vehicles. Labor strategists have put their money on a promise of 50 per cent of new-vehicle sales by 2030. Presumably the ramp up would begin soon after the forthcoming election.
The embodied energy (the energy expended in making an article from its component materials) is much greater for electric cars owing to the battery array and electronics. If the car-manufacturing industries in Japan and South Korea continue to use high-carbon emission energy sources it would take on average two to three years driving to compensate for the additional manufacturing emissions, depending on the renewable energy component of our electricity supply.
The situation is exacerbated by the strong preference of the Australian motorist for medium to large SUVs and utes over small cars. The embodied energy for batteries becomes very significant for the larger type of vehicle. Social engineering the tastes of the Australian motorist is about as hopeful as winning lotto.
Technology developments will determine the statistics of new cars in 2030. With the prospect of driverless vehicle fleets emerging in the urban environment governments are more likely to be concerned with ridership issues that affect the demand for energy.
Another example of misunderstanding and misinformation is the belief that electricity would be cheaper if all coal generators were replaced by wind and solar.
It is claimed that renewable energy is cheaper than the marginal cost of coal generation. That is, it is better economics for an electricity generator company that is investing in new plant to invest in renewables. What this means for the consumer is not clear especially as there is no sign of cheaper electricity from the growth in renewables, rather the contrary.
One reason that consumer costs are still increasing is that the traditional base-load coal generators are being powered down in order to use the supposedly cheaper renewable energy when it is available. Thus, there is more generator plant capacity being maintained than is needed and the coal generators are being used less efficiently. This is leading to a proliferation of roof-top solar, which is the most inefficient way to develop a national solar energy resource.
One thing is clear, renewables have complicated the infrastructure of electricity supply to the extent that not even experts agree on what should happen or what the cost will be.
The inaugural Integrated System Plan published in 2018 by the Australian Energy Market Operator outlines proposed developments in the eastern grid until 2040 when the largest technology sector will be solar and most of the coal generators will have been replaced. Yet some experts predict that the dominant renewable source will be wind generators. Either way, for renewables to dominate coal and gas there has to be large-scale development of the grid transmission capacity and energy storage.
It is said that wind generators operate at higher capacity at night and so complement solar. However, there are periods lasting for days when the output of the wind generators on the grid is well below average. For the three days ending on March 10, the aggregate output from all wind generators was less than half the average output. If coal generators are replaced by renewables these shortfalls must be met by having very large amounts of stored energy.
Despite renewable sourced electricity being cheaper at the farm gate the prospects are that electricity will be more expensive, whether the consumer pays by government spending or supply charges. The latest example of government spending is the announcement by the Prime Minister in February of a $1.38 billion taxpayer contribution to kick off the Snowy 2 pumped-hydro project that is expected to cost billions more. Yet the hydro-generator capacity of this investment will only be a small fraction of that required during peak demand periods when there is little wind and the sun angle is low.
Meanwhile the tenor of voter approval for more government action in the name of climate change suggests that some people think that Australia can actually do something to stop it, and the more government action the better.
In the real world there are five countries (China, US, India, Russia and Japan) that contribute 58 per cent of the world’s carbon emissions, while Australia belongs to a group of 15 countries that each contribute around one per cent for a total of 21 per cent. The balance of 21 per cent is contributed by about 170 small or developing nations.
It is a ridiculous course of action for Australia to outstrip other countries, especially China and India, in reducing carbon emissions. If China falls significantly short of the 26 per cent reduction from 2005 emission levels that Australia has committed to under the Paris agreement, it will have a massive impact on the amount of world emissions. On the other hand, if Australia were to increase its commitment to 45 per cent, as proposed by Labor, it will have negligible impact on world emissions.
The matter of unavoidable climate change is of enormous significance for Australia. The Intergovernmental Panel on Climate Change has signalled that it is unlikely that global warming can be contained to a 1.5C rise from pre-industrialisation levels. The increase has only been 0.8C to date but the frequency of extreme weather events in recent years may be seen as an indication of things to come.
Whether the fish kill that occurred in the lower Darling in January and February was due to drought or unwarranted harvesting and diverting of water for irrigation may be argued by the different sides, but either way the prospects for agriculture and water resources in the Murray-Darling basin are alarming.
ANU researchers have predicted that the Australian winter as we know it will be non-existent on the mainland by 2050. Concurrently a “New Summer” will develop in which temperatures will peak well above 40C for sustained periods.
Climate Change in Australia, an information resource made available jointly by the Department of the Environment, the Bureau of Meteorology and CSIRO, states that rainfall changes in southern Australia will be masked by natural variability for the coming decade, but winter and spring rainfall are projected to decline by 15 percent. Time spent in drought will gradually increase.
Australia’s priority should be to respond to the serious threat that unavoidable climate change poses for our agriculture and water resources and hope that the major industrialised countries address their overriding carbon emissions.
Developing the Fitzroy, Darwin and Mitchell River catchments in northern Australia as identified by CSIRO would be an appropriate start. Then given that we move in step with the rest of the world on our emissions reduction we will be best placed to face an uncertain future.