Archive for January, 2022

Covid in Context

January 24, 2022

With the recent surge in Covid-19, here is a progress report without the hype from the media, and without the commentary from those who doubt the impact of the disease.

I am attempting to show how Covid-19 compares with other major diseases in one important aspect: mortality.  How deadly is it?

I use data from the Australian Bureau of Statistics reports Provisional Mortality Statistics, Australia, Jan 2020 – Oct 2021 and Covid-19 Mortality, released 22 December 2021, and Our World in Data.  

To be certified as a Covid-19 fatality, Covid-19 must be the underlying cause of death- not dying of another condition while being positive for Covid.  According to Covid-19 Mortality, 71.2% of people dying from Covid had pre-existing chronic conditions.  The overall Case Fatality Rate (CFR) for Australia for COVID-19 as of 31 October 2021 was 1.0%, but while the CFR for those aged under 60 years was 0.1%, the CFR for males aged 90 years and over was close to 50%.   83% of people who died of Covid were over 70.  It is therefore a relatively mild disease for younger people, but very severe for elderly and sick Australians.

I shall now tease out mortality statistics to show Covid in context.

Figure 1 shows weekly death tallies of deaths in which doctors certified Covid as being the underlying cause of death, and from November weekly death tallies from Our World in Data.

Figure 1:  Weekly Covid Deaths from January 2020

Those who doubt the severity of Covid-19 often say that deaths from Covid are far less than from other causes.  Figure 2 shows total deaths for the past two years to October as well as the average from 2015-2019 (as 2020 was very unusual), together with Covid deaths.

Figure 2:  Covid-19 compared with all deaths per week

They have a point- to a point.  Weekly deaths from Covid in 2020 and 2021 were tiny in comparison, but in 2022 have risen to be a fifth of the average number for this time of year.  Breaking down the death toll to show separate diseases shows a different picture again.

Figure 3:  Covid-19 and other major diseases

Clearly, Covid’s weekly death toll is already greater than all other major killers except cancer, and may overtake cancer in another couple of weeks.  Thankfully we are close to the peak in eastern states.

Covid is a respiratory disease, but counted separately.  How does it compare with other respiratory diseases?  The next figure tracks Covid and total respiratory deaths, together with the average weekly deaths from respiratory illness from 2015 to 2019.

Figure 4:  Covid-19 and respiratory disease mortality

Covid already not only exceeds the weekly respiratory deaths for any time in the last two years (which had very little influenza), but also the highest average for 2015-2019.

I used to think Covid-19 was just another nasty infectious flu.  Not anymore.  Here’s a comparison of Covid deaths with deaths due to influenza leading to pneumonia.

Figure 5:  Covid-19 and influenza mortality

Already Covid-19 deaths are nine times the average for this time of year, and are also more than three times higher than the average in the peak of the winter flu season.

And WA has yet to open its border!

To compare mortality from diseases, the ABS calculates age-standardised death rates (SDRs) which “enable the comparison of death rates between populations with different age structures”.  Rates are calculated per 100,000 population.  Figure 2 shows death rates for the major diseases causing fatalities, including approximate (caution: not age- standardised) figures for Covid. 

Figure 6:  Death rates for Covid-19 and other major killers

Deaths will not stay at this high level for much longer.  There are signs we are close to the peak of new cases, and deaths will peak a week or two after that.  With Covid endemic in the community, mortality will fall to an unknown rate, and hospitalisations will become more easily manageable.

Make no mistake:  this is a deadly disease!  Take care!

Post Script: Here is another excellent resource:

https://www.covid19data.com.au/deaths

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Diurnal Temperature Range and the Australian Temperature Record: More Evidence

January 19, 2022

In an earlier post, I demonstrated through analysing Diurnal Temperature Range (DTR) that the Bureau of Meteorology is either incompetent or has knowingly allowed inaccurate data to garble the record.

A couple of readers suggested avenues for deeper analysis. 

Siliggy asked, “Is the exaggerated difference now caused by the deletion of old hot maximums and or whole old long warmer records?”

Graeme No. 3 asked, “Is there any way of extracting seasonal figures from this composition?”

This post seeks to answer both, and the short answer is “Yes”.

Using BOM Time Series data (from the thoroughly adjusted Acorn dataset) I have looked at data for Spring, Summer, Autumn, and Winter (although those seasons lose their meaning the further north you go).

DTR is very much governed by rainfall differences as shown by this plot.

Figure 1:  Winter DTR anomalies plotted against rainfall anomalies- all years 1910-2020

This shows that in winter DTR decreases with increasing rainfall.  The R squared value of 0.79 means that for the whole period, rainfall explained DTR 79% of the time on average.  However, the average conceals the long term changes in the relationship.

To show this, I simply calculated running 10 year correlations between DTR and Rainfall anomalies for each season, and squared these to show the “R squared” value.  This is a good rule of thumb indicator for how well DTR matches rainfall over 10 year periods.  A value of 0.5 indicates only half of the DTR for that decade can be explained by rainfall alone.  As you will see in the following figures, there are plenty of 10 year periods when the relationship was 0.9 or better, meaning it is ideally possible for 90% of DTR variation to be explained by rainfall.  Here are the results.

Figure 2:  Spring Running R-squared values: DTR vs Rain

There was a good relationship before 1930.  In the decades from then to the mid-1970s it was much worse, and very poor in the decade to 1946. It was poor again in the decade to 2001, and the 10 years to 2020 shows another smaller dip, showing something not quite right with 2020.

Figure 3: Summer Running R-squared values: DTR vs Rain

Summer values were very poor before the 1960s, especially the decades to 1944 and 1961, and dipped again in the 1990s.

Figure 4:  Autumn Running R-squared values: DTR vs Rain

The DTR/Rain relationship was very poor in the decades to 1928, and again before 2001.  The recent decade has also been poor- less than half of DTR to 2020 can be explained by rainfall.

Figure 5:  Winter Running R-squared values: DTR vs Rain

The DTR/rainfall relationship was fairly good, apart from two short episodes, until the 1990s.

I now turn to the northern half of the continent.

A large area of Northern Australia is dominated by just two seasons, wet and dry.  Here is the plot of northern DTR vs Rain for the wet season (October to April).

Figure 6:  Northern Australia Wet Season Running R-squared values: DTR vs Rain

Apart from the 1950s, the late 1970s-early 1980s, and 1998 to 2020, the DTR : Rainfall relationship is very poor, with a long period in the 1930s and 1940s in which rainfall explains less than half of DTR variation (only 13% in the decade to 1943). 

Because the northern half of Australia accounts for the bulk of Australian rainfall, and the wet season is from October to April, this perhaps explains the problems in spring, summer, and autumn for the whole country.

We can get some clues as to the reasons by comparing long term average maximum temperatures with inverted rain (as wet years are cool and dry years are warm).

Figure 7:  Northern Australia Wet Season Decadal Maxima and Rain

The divergence before 1972 and after 2001 is obvious.

The above plots show how poorly DTR (and therefore temperature, from which it is derived) has matched rainfall over the past 111 years.  Low correlations indicate something other than rainfall was influencing temperatures.

In reply to Siliggy, who asked “Is the exaggerated difference now caused by the deletion of old hot maximums and or whole old long warmer records?” the answer appears to be: both, however Figure 7 shows old temperatures (before 1972) appear incorrect, but recent temperatures are at fault too.

The mismatch shows that the Acorn temperature record is not to be trusted as an indicator of past temperatures- and even recent ones.

Tonga Volcano Shock Wave

January 17, 2022

The volcano that erupted near Tonga (and I won’t pretend I can spell let alone pronounce its name) sent a shock wave racing around the world.

It was detected at weather stations across Australia as a sudden spike followed by sharp drop about half an hour afterwards, as in this screenshot from Rockhampton.   

I used Google Maps to plot the course of the shock wave from the volcano across the widest part of Australia.

Showing just Australia:

I used BOM’s Weather Graphs of weather stations close to that line and found the times of the spikes and dips as the wave passed over.

It took roughly 3 hours and 24 minutes to cross the country.  That’s 3,953km at about 1,160 kph.

Here’s a quick plot of the speed of the shock wave as it crossed Australia.

It’s not often you get to see such a phenomenon.

The Challenge Ahead For Renewables: Part 3

January 16, 2022

In Part 1 I showed how the low Capacity Factors of wind and solar mean enormous wastage of resources and money has been incurred over the past 20 years. 

In part 2, I showed the impact of the policies of the major parties, with the costs of replacing fossil fuels in electricity generation, and the enormous cost of using renewables for all our energy use.

However, Net Zero is the goal of the whole developed world, not just Australia.  There are many, and not just the Greens, who say that replacing fossil fuel for all energy is not enough.  We must also ban all exports of coal and gas.

We produce far more energy than we consume- mainly coal (cue wailing and gnashing of teeth).  Most is exported.

According to the Department of Industry, Science, Energy and Resources (2021) total energy production (for domestic consumption plus exports of coal and gas) in 2019-2020 was 20,055 PetaJoules. 

Figure 1:  Australian energy production 2019-2020

All renewables and hydroelectricity amounted to a little over 2% of energy produced in Australia.

Figure 2:  Relative share of energy production

Therefore if we are to maintain our role as an energy exporter (of electricity or hydrogen), and thus our standard of living, then just to keep up with our 2019-2020 production, renewables will have to produce 48 times current production- an EXTRA 19,636 PJ. 

Figure 3: All renewables compared with energy consumption and production

Can this be achieved?

19,636 PJ is 5.45 billion MegaWattHours, which will need 622,227 MW generation (at 100% capacity).

If the extra generation is to come from solar (wind would require far too much land- over 6% of Australia’s land area), we will need an extra 4.149 million MW- 290 times 2020 solar capacity.

Therefore the cost would be at least

$7.47 TRILLION (if all solar).

And that figure doesn’t include storage, extra infrastructure like transmission lines and substations, charging points for vehicles, building hydrogen plants, and losses involved in electrolysis of water, conversion to ammonia and back again, and conversion of hydrogen to motive power.  Neither does it include the costs of decommissioning and replacement, safe burial of non-recyclable solar panels, turbine blades, and used batteries, nor the human costs of child labour in Congolese mines supplying cobalt for batteries.

(Australia’s nominal GDP will be around $2.1 trillion in 2022.)

Figure 4 shows the comparison between Australian GDP and the cost of solar generation needed.

Figure 4:  Cost of extra solar generation needed for Net Zero compared with the whole of the economy

So can it really be achieved?

In the minds of some, yes.

The report from the Australian Energy Market Operator (AEMO) containing the Draft 2022 Integrated System Plan (ISP) makes interesting (and scary) reading.  The favoured scenario is called “Step Change” which involves a rapid transformation of the Australian energy industry (rather than “Slow Change” or “Progressive Change”), which relates more to my analysis in Part 2.

However the scenario called “Hydrogen Superpower” received 17% of stakeholder panellists’ votes in November 2021 and must be considered a possible political goal.

Here is a summary of the Step Change and Hydrogen Superpower scenarios:

• Step Change – Rapid consumer-led transformation of the energy sector and co-ordinated economy-wide action. Step Change moves much faster initially to fulfilling Australia’s net zero policy commitments that would further help to limit global temperature rise to below 2° compared to pre-industrial levels. Rather than building momentum as Progressive Change does, Step Change sees a consistently fast-paced transition from fossil fuel to renewable energy in the NEM. On top of the Progressive Change assumptions, there is also a step change in global policy commitments, supported by rapidly falling costs of energy production, including consumer devices. Increased digitalisation helps both demand management and grid flexibility, and energy efficiency is as important as electrification. By 2050, most consumers rely on electricity for heating and transport, and the global manufacture of internal-combustion vehicles has all but ceased. Some domestic hydrogen production supports the transport sector and as a blended pipeline gas, with some industrial applications after 2040.

• Hydrogen Superpower – strong global action and significant technological breakthroughs. While the two previous scenarios assume the same doubling of demand for electricity to support industry decarbonisation, Hydrogen Superpower nearly quadruples NEM energy consumption to support a hydrogen export industry. The technology transforms transport and domestic manufacturing, and renewable energy exports become a significant Australian export, retaining Australia’s place as a global energy resource. As well, households with gas connections progressively switch to a hydrogen-gas blend, before appliance upgrades achieve 100% hydrogen use.

Household gas switching to 100% hydrogen? What could possibly go wrong?

Here are the AEMO projections:

“The ISP forecasts the need for ~122 GW of additional VRE by 2050 in Step Change, to meet demand as coal-fired generation withdraws (see Section 5.1). This means maintaining the current record rate of VRE development every year for the decade to treble the existing 15 GW of VRE by 2030 – and then double that capacity by 2040, and again by 2050.”  (VRE= Variable Renewable Energy)

 “In Hydrogen Superpower, the scale of development can only be described as monumental. To enable Australia to become a renewable energy superpower as assumed in this scenario, the NEM would need approximately 256 GW of wind and approximately 300 GW of solar – 37 times its current capacity of VRE. This would expand the total generation capacity of the NEM 10-fold (rather than over three-fold for the more likely Step Change and Progressive Change scenarios). Australia has long been in the top five of energy exporting nations. It is now in the very fortunate position of being able to remain an energy superpower, if it chooses, but in entirely new forms of energy. “ (p.36)

Figure 5:  Projections of different renewable needs from the draft report

And capacity factors have not been considered!

And here are the “future technology and innovation” ideas for reducing emissions:

Figure 6: How to achieve emissions reductions

I’m glad I won’t be around to see this play out.

The Challenge Ahead For Renewables: Part 2

January 13, 2022

In Part 1 I showed how the low Capacity Factors of wind and solar mean enormous amounts of wastage of resources and money have been incurred over the past 20 years. 

I also said that the wastage can only get worse.  Here’s how.

In Part 1, I only looked at historical electricity generation.  What of the future according to the major political parties? (The Greens don’t count because they can’t count.)

The major parties are committed to Net Zero emissions by 2050, which will require massive changes to our energy use.

I use data from the BP Statistical Review of World Energy 2021, the National Energy Market website, and the report of the Department of Industry, Science, Energy and Resources (2021).

To replace 2020 fossil fuel electricity with renewable electricity will require an extra 200.6 TeraWattHours:

Figure 1:  Total Electricity Generation

That’s an extra 22,884 MegaWatts of renewable capacity at 100% capacity factor.  Remember, wind’s capacity factor is about 32%, and solar is about 15%.  At $1.8 million per MW, that will cost somewhere between 129 and 275 billion dollars. 

That is of course entirely achievable.  Costly, but achievable.

However, electricity makes up only a small part of Australia’s total energy use.  Transport alone uses much more.  That is why there is a push for more electric vehicles: the ALP wants 89% of new car sales to be electric vehicles by 2030.

Australia’s 2020 energy consumption was 5,568.59 PetaJoules, a decrease of 5.25% on 2019.  One PetaJoule is the equivalent of 0.278 TeraWattHours, or 277,778 MegaWattHours, which is the power generated by 31.7 MW over one year.

Figure 2:  Total Energy Consumption in Australia

Renewables of all sorts accounted for just 8% of energy consumed in Australia in 2020.  Include hydro and that rises to 10.4%.  Figure 2 shows the amount for each.

Figure 3:  Energy Consumption by Type

Note the complete absence of nuclear energy.

If Australia is to be completely fossil fuel free (with no increase on 2020 consumption, which was reduced because of Covid), renewables will have to produce an extra 4,990.9 PetaJoules.  Our consumption will look like this:

Figure 4:  Energy Consumption without Fossil Fuels

4,990.9 PJ is 1.387 billion MegaWattHours, which will need 158,152 MW generation (at 100% capacity)- only 27.8 times 2020 generation.

If this is to be supplied by wind alone, we will need an additional 494,225 MW of installed capacity in wind farms- 52 times 2020 wind capacity- at 24 Hectares per MW.  An extra 118,600 square kilometres of suitable land for wind farms will be difficult to find.

Solar at 2-3 Hectares per MW would probably be a better proposition.  If the extra generation is to come from solar, we will need an extra 1,054,357 MW- 60 times 2020 solar capacity.

Therefore the cost of meeting our current energy consumption- transport, domestic, commercial, and industrial- with no allowance for growth, and ignoring the cost of converting our entire domestic, commercial, industrial, mining, and air transport capacity to some form of electric vehicles, would be between:-

$ 889.6 BILLION  (if all wind)

and

$1.898 TRILLION (if all solar).

(Australia’s nominal GDP will be around $2.1 trillion in 2022.)

That’s up to $73,700 for every man, woman, and child in Australia.

Figure 5 shows the comparison between Australian GDP and the cost of solar generation needed.

Figure 5:  Cost of extra solar generation compared with the whole of the economy

How much of that investment would be in wasted capacity? Between 68% and 85%-from $605 Billion to $1.613 Trillion.

Moreover, the life of a wind turbine is 20 to 25 years, and 25 years for solar panels, so we can look forward to more expense in decommissioning and replacement in the future.

(By the way- do you think that “future technology and innovation” will be any cheaper?)

That’s just what would be the result of the major parties’ commitment to Net Zero.

But wait- there’s more. Stand by for Part 3.

The Challenge Ahead For Renewables: Part 1

January 11, 2022

As we are committed by all major parties to the goal of Net Zero emissions by 2050 perhaps we need to reflect on the scale of the challenge ahead.

I shall first deal with electricity, as that is the only thing that renewables such as wind and solar can produce (except perhaps for a warm inner glow in those who love them.)

Being less of a romantic, I prefer facts and figures.  In this post I use data from the BP Statistical Review of World Energy 2021, the National Energy Market website, and by tracking down opening and closing dates for various facilities.

Figure 1 shows the total generating capacity for coal, wind, and solar electrical generation for the last 20 years.  (Gas is excluded as it makes up less than 8% of generation over a year.)  This is the maximum possible output if all plants are operating at 100% of their rated capacity.

Figure 1: Generating Capacity 2021 – 2020

Note how coal fired electrical capacity fell below 25,000 MegaWatts (MW) with the closure of power stations in SA, WA, and Victoria.  Meanwhile from a very low base wind capacity rose steadily and accelerated from 2018.  Solar generating capacity has exceeded wind since 2012 and really took off in 2019 and 2020.  Wind and solar combined now exceed coal generating capacity.

Now let’s look at how much electricity was actually produced

Figure 2: Coal Capacity and Generation 2021 – 2020

Note how coal generation is falling steadily.  The gap between generation and capacity may be regarded as wasted resources (and money).  This has remained fairly constant over the years.

Figure 3: Wind Capacity and Generation 2021 – 2020

Despite the large increase in capacity, generation is not increasing as fast.  The gap is widening.

Figure 4: Solar Capacity and Generation 2021 – 2020

Again, the gap (i.e. waste) is increasing even faster.  More on this later.

Here’s another way of looking at this problem, for solar.

Figure 5: Solar Generation as a Factor of Installed Capacity 2021 – 2020

Over the last 20 years there has been a fairly constant and close relationship between the amount of electricity generated and the installed capacity it is produced from.  This illustrates the low capacity factor of renewables.  Capacity factor is average actual generation divided by the nameplate capacity, usually expressed as a percentage. 

Figure 6: Capacity Factor 2021 – 2020

Coal has a capacity factor of between 65% and 80%.  Hydro depends on rainfall and has averaged 21% over the last 10 years.  Wind averaged 32% over the last 10 years, but solar struggles to get above 15%- mainly because it sits idle at night, there are large losses in conversion from DC to AC, and also because it produces more than the grid can handle in the middle of the day so supply is curtailed. 

Investors take heed: for every MegaWatt of solar electricity you may wish to generate, you will need to install 6.7 MW.  Every 1 MW of wind electricity needs 3.125 MW installed.  But wind takes up about 24 Hectares of land per Megawatt as against 2-3 Hectares for solar.

Figure 7 shows how much investment has been wasted over the years.

Figure 7: Wasted Capacity

Waste costs money.  In the case of wind and solar, $1.8 MILLION per MW.

I hate waste- but it can only get worse.