Deadly NOx pollution

 From The Australian Broadcasting Corporation (ABC)

Imagine you're stopped at the lights and two cars pull up beside you. One is a compact SUV, the other a beefy four-wheel drive that weighs twice as much.

The off-roader has a petrol engine, while the SUV has the low idling growl of a diesel.

You'd probably guess the big car is polluting more. 

And you're right, but also wrong.

The smaller car emits less carbon dioxide (CO2) but it also produces more of another form of car pollution — one that has a much greater immediate public health impact than the CO2.

Nitrogen dioxide (NO2) and nitric oxide (NO) are collectively known as the oxides of nitrogen, or "NOx".

Mostly invisible and regularly ignored, NOx is linked to hundreds of premature deaths each year from conditions such as heart and lung diseases.  

Despite this health toll, drivers are generally unable to find out exactly how much NOx their car emits. 

Now, new publicly available data is exposing which popular models pump out more NOx than others.

It comes as a long-anticipated standards update goes into force today that more than halves how much NOx new diesel models sold in Australia may emit.

Here's how these changes may affect your next car — and the air you breathe. 

Unlike with CO2, you won't find a point-of-sale windshield sticker or a vehicle emissions guide that lists NOx pollution.

Cars sold in Australia must emit less NOx than mandated maximums, under rules last updated nine years ago.

These rules are enforced by laboratory testing of new models. Tyres are spun on a giant treadmill while exhaust gases are funnelled, split, and measured.

But lab-testing doesn't necessarily show how much cars pollute on the road.

The Australian Automobile Association (AAA) recently strapped emissions measurement systems onto more than 100 of the most popular cars, utes [pick-up trucks] and vans. They drove these modified vehicles around Geelong in real traffic conditions, following strict protocols for speed and acceleration.

Their testing revealed many cars consumed more fuel and emitted more pollution than lab tests showed.

And some of the biggest discrepancies were for NOx emissions.

The petrol cars were generally under the limit. Two of the 90 petrol cars tested emitted more NOx than the mandated maximum of 60 milligrams per kilometre.

But most of the diesel cars flunked the test.

Seventeen of the 24 diesels tested emitted more than the cut-off limit for commercial or passenger models, which is 280 milligrams per kilometre and 180mg/km respectively (two to three times higher than the limit for petrol cars).

On average, diesel vehicles exceeded their mandated maximums by almost 40 per cent [and remember, the emissions standard for commercial vehicles is 3 - 4 times higher than for petrol cars]

And this wasn't for a new emissions standard. The maximum had been in place since 2016.

Dots on a graph may not look too dangerous, but incremental changes in NOx emissions have a measurable impact on public health, when multiplied by the millions of cars.

If you stand beside a busy road and count the passing cars, about one in every 10 vehicles burn diesel.

Diesel vehicles are less common than petrol ones but emit far more NOx (based on the AAA's data, about 20 times more).

NOx exposure is associated with the majority of deaths from traffic pollution, so the relatively few diesel cars have a disproportionately high public health impact.

Research led by the University of Tasmania's Centre for Safe Air estimates particulate and NOx pollution from traffic leads to more than 1,800 earlier than expected deaths a year.

"Motor vehicles are one of the most important sources of air pollution in Australia," the Centre's director Fay Johnston said.

NO2 is a reddish-brownish gas with an acrid odour, while NO is colourless and odourless.

A near-invisible haze of NOx spreads outwards from highways and suburban streets. Levels drop at about 100 metres to 200m from the source, but remain high in busy traffic areas.

Breathed in, long-term exposure to NOx can damage the lungs and lead to diseases like bronchitis and asthma. It generally inflames and stresses cells in the body, which is linked with heart disease.

"We can measure the increased rates of deaths when NOx pollution is higher," Professor Johnston said.

Despite this high public health impact, Australia has delayed tightening vehicle NOx pollution regulations and is now about a decade behind Europe, the UK and the US.

The AAA's results show a 2024 Toyota LandCruiser Prado (GXL) diesel and a 2024 Mitsubishi Pajero Sport (GSR) diesel have very similar fuel consumption and CO2 emissions.

But the Pajero's NOx emissions are about 17 times higher than the Land Cruiser's.

The reason for this is "after treatment", or the process of cleaning exhaust gases after they come out of the engine.

The most effective method is to inject a nitrogen-rich additive, like AdBlue, into the hot exhaust gases, which converts the NOx into nitrogen gas (N2), water (H2O) and CO2. This is known as selective catalytic reduction (SCR).

The 2022 Toyota Land Cruiser Prado uses SCR, while the 2024 Mitsubishi Pajero Sport does not.

SCR is so effective that it can make a diesel emit as much NOx as a petrol car — and even less than some petrol cars.

Essentially all diesels now sold in Europe use SCR to comply with emissions standards, Shawn Kook, director of the UNSW engine research laboratory, said.

Europe's had these standards since 2015. 

"The technology and products are there," Professor Kook said.

"It is just that [adding this technology] will add costs to car makers."

AdBlue is stocked at petrol stations around Australia. (Getty: John Keeble)

1800 dead per year!  Imagine if it was terrorists or murders!  Over the last 12 months, there were 1361 road deaths in Australia.   There were 227 murders.   

Wave energy trial wraps up

From The ABC

A Melbourne-based company behind the country's first successful wave energy trial says it is unlikely to set up in Australia, thanks to a lack of political and financial support.

Wave Swell Energy chief executive Paul Geason said he was "delighted" with the results of the multi-million-dollar pilot project off the coast of King Island, and believed the technology would become an important part of future global electricity production.

However, Mr Geason said a lack of incentive from both state and national governments has meant the country will miss out on becoming home to the "world-leading" technology, adding the company would shop its designs on the international market.

"We are an Australian, a Tasmanian invention. Australia's an important market for us … we'd dearly love to set up here," he said.

"Ideally, Australia would become home to a world-leading manufacturing capability for these wave energy converters."

"But right now … there are other markets in the world that are further advanced. Frankly, it would be irresponsible for us not to participate in those opportunities."

In late 2020, Wave Swell Energy constructed a 1,000-tonne generator at Tasmania's Port of Bell Bay, with the aim of harnessing the relentless power of the Bass Strait near King Island.

The two-part structure, designed as a type of artificial blowhole, was then tugged for 40 hours over to waters near Grassy on King Island's east coast where it began harvesting electricity and feeding it into the local grid.

Its wave energy technology is based on the concept of an oscillating water column (OWC).

The OWC is an artificial blowhole consisting of a chamber that is open underneath the waterline. As waves pass through, the water rises and falls inside, forcing the air to pass by a turbine at the top of the chamber — this turbine generates electricity.

Electricity from the unit was delivered to shore by a subsea cable connected to King Island's 11-kilovolt distribution system.

After a year, the trial was declared a success, marking the first time in Australian history the chaos and power of the ocean had reliably generated electricity for homes.

It followed numerous failed projects including a wave generator that sank and rusted for seven years in South Australian waters, and a second generator made by the same company that sank near NSW's Port Kembla.

Only ever intended as a limited pilot run, the unit was decommissioned this week, kicking off with the complex task of floating the structure that has sat on the sea floor and towing it about 2 kilometres inshore.

"It's been sitting in that location on the seabed under its own weight for over two years now," Mr Geason said.

"It was important to be able to float the unit successfully … I can't tell you how my spirits were raised when we were informed by the local team it was floating. It was extraordinary."

He said the next step would be to build a 30-metre land bridge out to the unit, where a crew would spend the next three to four months disassembling and recycling all the components.

He said the electrical systems would be salvaged, while the concrete components would be crushed and used by King Island Council for road repairs.

"It was a pretty hectic couple of days," Mr Geason said, speaking on Tuesday evening.

"It's essentially a mobile power station that can be re-floated, so we're really excited to have proven that.

"When you think about the challenges in recycling solar … wind turbine blades … We also thought it was important to show that we could 100-per-cent recycle the kit."

Despite the success of the pilot in Australian waters, Mr Geason said the company would be setting its sights on the overseas market, meaning the technology is unlikely to be feeding Australian homes in the near future.

"The next step for us … it's really about scaling up, it's really about getting more units and bigger units into the water," he said.

He explained that while Australia's oceans were perfect for the technology, the political scene was not.

He said he had high hopes for the European market, where progressive policies and political funding made the market alluring for new energy technology.

A federal Department of Climate Change, Energy, the Environment and Water spokesperson confirmed the government had contributed $4.03 million to the pilot.

The funding was part of a $63.8 billion commitment to 16 wave or marine energy projects worth $148 million in total.

The spokesperson said the government had also recently set aside $3 billion for renewables, including clean energy component manufacturing, but made no comment on the Wave Swell Energy generator seeking investment overseas.

Wave energy is unlikely to provide all our electricity, but it would be a useful addition, because it is more or less uncorrelated with other energy sources.  Waves can be created by winds a thousand kilometres away, so that even if the air is still, the wave energy generator will still produce power.

Doomsday glacier could melt 'with just a small kick'

From the ABC (Australian Broadcasting Corporation)

Scientists have used an unmanned submarine to map underwater terrain near a massive melting glacier in West Antarctica for the first time, showing it has the potential to retreat at twice the speed observed by satellites over the past decade.

The Thwaites Glacier, named after glacial geologist Fredrik Turville Thwaites, is known as the "doomsday glacier" in some circles because of its potential to significantly raise global sea levels, as well as its vulnerability to rapid melting due to warming ocean water.

A team of researchers from the United States, the United Kingdom and Sweden travelled to Antarctica on the icebreaking research vessel Nathaniel B. Palmer in early 2019 to map a former grounding zone of the glacier — the area where an ice shelf attached to solid ground gradually transitions into a floating ice shelf.

The researchers hoped that by studying Thwaites Glacier's past retreat, they could gain a new understanding of what it has the potential to do in the future, amid speculation it could be a possible candidate for climate engineering projects to prevent further collapse.

They used a bright orange autonomous underwater vehicle (AUV) named Rán, mounted with two types of geophysical sensors, to produce 3D scans of the underwater surface.

The 19-hour mission produced about 13 square kilometres of new geophysical data, gathered from between 50 and 90 metres above the sea floor.

By analysing the amplitude and spacing of ridges left by the glacier on a raised part of the sea bed — an isolated underwater outcrop they called "the bump" at the south-west corner of the glacier's tongue — they were able to determine that the markings, or "ribs", had been left by the glacier lifting and settling with the ocean tide each day.

They found the Thwaites Glacier was indeed susceptible to rapid retreat, having been shrinking at a rate of more than 2.1 kilometres per year when the markings were left.

That is twice the rate of retreat observed via satellite between 2011 and 2019, previously thought to have been the upper limit of the glacier's potential shrinking speed.

The University of Florida's Dr Alastair Graham, who led the mission to Antarctica and was lead co-author of a study published on Monday in Nature Geoscience, said the glacial retreat documented by the team would have occurred sometime over the past two centuries, possibly as recently as the mid-1900s.

While he called the opportunity to map the area "truly a once-in-a-lifetime mission", he was at pains to point out that what they had found shattered the previously held hope that Antarctic ice sheets could be sluggish and slow to respond to changes in climate.

"Just a small kick to Thwaites could lead to a big response," Dr Graham said.

Dr Robert Larter, a marine geophysicist and co-author of the study, said once the glacier retreats beyond a shallow ridge in its bed, it has the potential to shrink at an even greater rate.

"Thwaites is really holding on today by its fingernails, and we should expect to see big changes over small timescales in the future — even from one year to the next," he said.

Multibeam bathymetry images captured by Rán show "ribs" and melting channels on underwater terrain near the Thwaites Glacier.(Nature Geoscience)

Improved fleece on sheep grazed under solar panels

From The ABC

Sheep grazing under solar panels at farms in NSW's Central West have produced better wool and more of it in the four years since the projects began, according to growers.

Local graziers have labelled the set-up a "complete win-win", with the sheep helping to keep grass and weeds down so as not to obscure the panels.

In turn, the panels provided shade for the sheep and grass, and helped prevent the soil from drying out.

Wool broker Graeme Ostini, who has been grazing merino wethers at a solar farm near Parkes in a trial with the Parkes Show Society, said he had seen the benefits of running the animals under panels.

He said his sheep were slightly lighter stocked than the average in the district but were cutting an "amazing" amount of wool.

"It is actually quite astonishing. Some of the sheep look fantastic. They're growing exponentially and the wool cuts are in the top 5 per cent in the district."

He said he credited the good season and the solar panels for the improvement.

While Mr Ostini's sheep were lighter stocked than average, Dubbo farmer and grazier Tom Warren's were slightly higher.

Mr Warren leases part of his land to a solar farm and runs about 250 merino ewes and wethers on 54 hectares among the panels.

Like Mr Ostini, Mr Warren also reported impressive results.

He has not noticed an increase in wool quantity but said the quality had improved.

"It'll be because of the conditions the sheep are living in," he said.

"It's relatively clean, without burrs, without dust. There's very, very little contamination of the wool and they're protected from the sun as well."

Mr Warren said the carrying capacity of the land had also increased by about 25 per cent.

During the drought, water condensed on the solar panels in the mornings. The trickling of the water to the grass below keep strips of pasture green.

In all, he said by leasing his land to the solar farm and grazing his sheep there, his income had increased.

Mr Warren's sheep were able to graze almost all through the drought years thanks to condensation from the panels.(Supplied: Tom Warren)

The sand battery

From the Australian Broadcasting Corporation (ABC)

The idea of storing heat in sand to warm homes through winter may, on the face of it, seem too simple to work.

Drop a load of cheap builder's sand in an insulated silo, heat the sand with renewable electricity, and then tap the stored thermal energy for months on end.

In an age of green hydrogen, lithium-ion batteries and other high-tech energy solutions, it can't work, right?

Finland begs to differ. This month saw the Nordic nation launch the world's first commercial "sand battery".

 

Heat-storing sand batteries like this one in Finland could become a familiar sight at Australian factories looking to cut their gas bills.(Supplied: Polar Night Energy)

 

About 230 kilometres north-west of Helsinki, in the town of Kankaanpää, homes, offices and the public swimming pool are being heated by thermal energy stored in a 7-metre steel container filled with 100 tonnes of sand.

So how does it work, what else can it be used for, and should we build them in Australia?

The Kankaanpää sand battery is connected directly to the grid and runs when electricity is cheapest.

Hot air blown through pipes heats the sand in the steel container by resistive heating (this is how electric heaters work).

The sand is able to store heat at around 500–600 degrees Celsius for months, so solar power generated in the summer can be used to heat homes in the winter.

It can store up to 8 megawatt-hours of energy, which is the capacity of a large, grid-scale lithium battery.

The project was the work of Finnish startup Polar Night Energy and a local Finnish utility Vatajankoski.

Polar Night Energy's chief executive officer Markku Ylönen said the entire battery could be built in "any steel workshop".

"It's really a typical silo with nothing that special," he said.

To discharge the stored thermal energy, air is circulated through pipes in the sand where it's heated, then directed, to wherever it's needed.

Right now, that's mostly heating homes, but it could also be used for high-temperature industrial processes, Mr Ylönen said.

Very little energy is lost in this process, so long as the heat is not being transported very far, he said.

In theory, the stored heat could be used to drive a steam turbine to generate electricity, but this is far less efficient.

"The efficiency will be something like 20–25 per cent," Mr Ylönen said.

"Technologically speaking, there are no obstacles, but the economic case is harder to find than with heat-only projects."

Australia doesn't have the same domestic heating requirements as Finland, but there's plenty of potential for using stored thermal for industrial processes, said Andrew Blakers, director of the ANU Centre for Sustainable Energy Systems.

"There's an enormous storage market for these things and that is to replace gas in factories," Professor Blakers said.

About 16 per cent of Australia's emissions are due to burning of gas in industry for processes needing high temperatures (anything above 100C).

Heat pumps (the same technology used by reverse cycle air-conditioners), which can be powered by renewables, max out at about 100C, meaning they can't replace gas for these industrial uses.

But thermal storage can deliver temperatures of more than 1,000C, depending on the storage medium.

"You choose the storage medium to suit the temperature of the process," Professor Blakers said.

Sand is just one option. Others include crushed rock and molten salt.

The idea of thermal energy storage, including the sand battery concept, has been around for years.

So why are we only building these heat batteries now?

Firstly, for many years it's been cheaper to burn gas to generate high temperatures.

Secondly, due to heat loss, thermal energy can't be transported as easily as pressurised gas, which can make it trickier to use.

But recently the economics have changed.

Russia's invasion of Ukraine has disrupted the supply of gas to Europe and other markets.

In the first quarter of 2022, European gas spot prices were five times higher than in the first quarter of 2021.

These high prices led to Australian gas producers exporting their gas, rather than selling it domestically, driving up prices in Australia.

Thermal storage has become cheaper than burning gas for high-temperature industrial processes, Professor Blakers said.

"In the past three years, the price of solar and wind has fallen so far, and [in the past few months], the price of gas has gone through the roof.

But factories looking to switch to thermal storage won't be able to simply pipe in heat, like they do with gas.

Instead, they'll have to build their own thermal storage silos and heat them with cheap daytime solar electricity, from their own rooftop systems or the grid.

"A few thousand cubic metres of storage would be enough to keep a factory running," Professor Blakers said.

Or factories could wait for gas prices to fall.

"I think they'd be nuts if they waited," Professor Blakers said.

"Nobody can predict where the gas price will go, but the one thing you know is daytime solar electricity is going to stay at a low price."

The Australian start-up 1414 Degrees has developed and patented a thermal storage system similar to the Finnish battery, but using molten silicon to store heat instead of sand.

It recently teamed up with another company, Vast Solar, to plan a solar thermal project in South Australia.

The proposed Vast Solar solar thermal project in South Australia.(Supplied: Vast Solar)

 

Swedish public utility Vattenfall is also building a 200MW-rated thermal energy storage in Berlin.

The heat storage tank can hold 56 million litres of water, which will be heated to 98C to warm homes.

Polar Night Energy has had plenty of interest in building more sand batteries, with the war in Ukraine putting the focus on alternative energy sources and storage methods, Markku Ylönen said.

Recently Moscow suspended the supply of gas and electricity to Finland due to its request to join NATO.

The next battery will be 100 times bigger, or about 20 metres in diameter and 10 metres high, with 1GWh of energy, Mr Ylönen said.

"With the economies of scale, if we go 100 times bigger, the price won't be 100 times larger. It will be 20–30 times larger.

"It will be in Finland, but we are already negotiating several sites internationally."

Once the first of these larger designs is built and tested, others could be built rapidly, he said.

"I would [eventually] like to say that we are building 10 next year."

Fewer than 50% of Ozzies are Christian

 From the ABC (Australian Broadcasting Corporation)

Australians are increasingly unlikely to worship a god and more likely to come from immigrant families.

The 2021 census has revealed a growing nation — more than 25 million people — that is more diverse than ever.

It also depicts a country undergoing significant cultural changes.

For the first time, fewer than half of Australians identified as Christian, though Christianity remained the nation's most common religion (declared by 43.9 per cent of the population).

Meanwhile, the number of Australians who said they had no religion rose to 38.9 per cent (from 30.1 per cent in 2016).

The data also shows almost half of Australians had a parent born overseas, and more than a quarter were themselves born overseas.

Christianity was the stated religion of about 90 per cent of Australians until 1966, when its dominance began to wane.

The ABS says migration has affected the trends since, though much of the change is due to the growth of atheist and secular beliefs.

The fastest-growing religions, according to the latest census, are Hinduism (2.7 per cent of the population) and Islam (3.2 per cent), though these worshippers remain small minorities.

The 2021 census was also the first to collect data since same-sex marriages were allowed in Australia.

Almost 24,000 of these marriages were officially recorded.

However, marriage itself is becoming less prevalent.

A generation ago (in 1991), 56.1 per cent of Australians aged over 15 were in a registered marriage. That has now dropped to 46.5 per cent.

Cutting farming's climate impact

The burps and farts of ruminants (cows) are a key source of methane, which is a powerful greenhouse gas, 90 times more potent than CO2 over ten years.  Fortunately, methane decays within 10 years to CO2, so if we could cut its emissions, we could quickly remove a major greenhouse gas from the system.  Of course, giving up meat and going vegan would do the trick, but many are not prepared to change the habits of a lifetime (full disclosure: I am vegan).  So it's good news that a kind of seaweed may do the trick.

From The Australian Broadcasting Corporation (ABC)

A company commercialising a CSIRO-developed, seaweed feed product, which slashes the amount of greenhouse gases cattle burp and fart into the atmosphere, has won a $1 million international prize for its work reshaping the food system.

CSIRO-affiliated company Future Feed said it would use its Food Planet Prize winnings to create an international commercial fund to help First Nations communities generate income from cultivating and selling the seaweed.

According to the science agency, methane emissions from livestock make up around 15 per cent of global greenhouse gas emissions, and one cow produces on average as much gas emission as one car.

The CSIRO says on its website that methane stays in the atmosphere for about nine years, a far shorter period than carbon dioxide.  However, its global warming potential is "86 times higher than carbon dioxide when averaged over 20 years and 28 times higher over 100 years".

Future Feed director and CSIRO scientist Michael Battaglia said that when added to cattle feed, the product, which contains Australian 'super seaweed' Asparagopsis, virtually eliminated methane from the animals' bodily emissions.

"We know that just a handful [of the product] per animal per day, or 0.2 per cent of their diet can virtually eliminate 99.9 per cent of methane," Dr Battaglia said.  He said the potential for the product to reduce the world's greenhouse gas footprint, if commercialised, was massive.  "We think we can tackle the dairy and the feedlot part of that pretty simply, which may be 5 megatons in Australia and globally 500 megatons of emissions," Dr Battaglia said.  

"That's equivalent to taking 100 million cars off the road.  "But in the long run, if we can start to think about ways to deliver this into grass-fed sectors, the impact is 10 to 100 times more than that."

From The  Guardian newspaper

Feeding seaweed to cows is a viable long-term method to reduce the emission of planet-heating gases from their burps and flatulence, scientists have found.

Researchers who put a small amount of seaweed into the feed of cattle over the course of five months found that the new diet caused the bovines to belch out 82% less methane, a potent greenhouse gas, into the atmosphere.

The finding builds on previous research that showed that seaweed could reduce cows’ methane output over a shorter timespan. “We now have sound evidence that seaweed in cattle diet is effective at reducing greenhouse gases and that the efficacy does not diminish over time,” said Ermias Kebreab, director of the World Food Center and an agricultural scientist at University of California, Davis.

Kebreab conducted the research, published in Plos One, with Breanna Roque, a PhD graduate student.

Cows produce methane via microbes in their stomachs as they digest their fibrous food, in a process a little like fermentation. Methane is shorter-lived in the atmosphere than carbon dioxide but is more than 30 times as effective in trapping heat, making it a major greenhouse gas. A type of seaweed called Asparagopsis taxiformis can partially counteract these emissions from cows.

The seaweed Asparagopsis almost eliminates methane gas from cattle if put in their feed.(Supplied: Future Feed)