29/03/2021

(AU) Victoria’s Grid Runs On 50 Per Cent Renewable Energy For First Time

The Age - Noel Towell

Victoria has powered its electricity grid with 50 per cent renewable energy for the first time, well ahead of state government projections for the transition to clean energy.

The state Labor government says the historic breakthrough, enabled by the cool spring and summer, shows Victoria is well on its way to replacing the carbon-intensive brown coal generators that still provide the vast bulk of the state’s electricity along with wind, solar and hydroelectric power.

New data shows that on three dates between November and January, renewables soared to more than 40 per cent of the state’s daily supply and went above 50 per cent in about 12 instances during two periods in mid-January and mid-November, all on days with temperatures of 30 degrees or below.

But the surge of wind and solar energy into the state’s grid is piling financial pressure on the remaining coal-fired power stations in the Latrobe Valley, which are still essential to keeping electricity supplies stable and bills down.

The announcement this month that the giant Yallourn coal burning plant – which supplies about 22 per cent of the state’s power – would close in 2028 has thrown the spotlight back onto Victoria and Australia’s energy transition away from fossil fuels.

The federal government warns that the 1450 megawatts of electricity produced by the Yallourn plant cannot be replaced without some form of new fossil fuel generation and is championing gas as a “transition fuel”.

The share of renewable energy powering Victorian homes and business has grown from 9 per cent in 2010 to more than 26 per cent in 2020, just exceeding the legislated 25 per cent target.

Victorian Energy and Environment Minister Lily D’Ambrosio told The Sunday Age the new figures showed the state was on track to fill the gap left by Yallourn, and the subsequent closures of the Loy Yang A and B plants, with renewables, with batteries to provide stability and rebuilt to deliver the power.

“Between now and 2028 , we will be delivering an additional 5000 megawatts of new power supply plus batteries, so we then have more than enough supply to meet our needs,” the minister said.

“The grid connections are a really critical issue and that’s a critical issue right across the National Electricity Market, not just for Victoria.

“We’re investing more money into grid upgrades than Queensland and NSW combined; there was $540 million over four years in our budget in November.” 

'From sunny north to windy east': What are Victoria's renewable energy zones? 
Ms D’Ambrosio said the question of peak demand, which cannot currently be met by renewables, was being addressed by the construction of five large scale batteries, three of which were already built with two connected to the grid. 

But Federal Energy Minister Angus Taylor, who said he shared the priority of retiring the big coal generators ahead of time, does not believe the job of replacing Yallourn’s capacity could be done just by wind, solar, batteries and hydro.

”Solar and wind can provide us energy, but it can’t be guaranteed... so you need that back-up...whether it’s through projects like Snowy [Hydro 2]... gas, or whether it’s batteries, all of those technologies will play a role in providing that backup.

“If we don’t have that, we will see blackouts, and we will see higher prices.”

Jeff Dimery, chief executive of Alinta Energy which owns the Loy Yang B plant, said market reform was badly needed as coal-fired stations struggled to compete on price against renewable providers who were selling electricity produced at zero cost or even being paid, via government subsidies, to generate power.

“If something doesn’t change in the medium term, our operation would become very marginal,” Mr Dimery told The Sunday Age.

“We’re the newest and lowest cost marginal generator and if we end up in a situation where we’re marginal and it pretty much tells you that everybody else is unviable, and that may be the outcome that we’re destined for.

“My concern, as an energy industry expert, is the market can’t sustain the closure of all the coal fired power stations in such a rapid time frame and expect the lights to stay on.

“So something’s got to give.”

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(AU) Meet The Giant Mechanical Stomach Turning Food Waste Into Electricity

ABC News - Gian De Poloni

Meet the mechanical stomach turning food waste into electricity.
Tonnes of food scraps collected from restaurants and supermarkets are being converted into electricity under a green energy initiative powering thousands of homes in Perth.

The City of Cockburn has made the waste to energy service a permanent fixture of its general duties, collecting rotting food waste from local businesses and feeding it to a mechanical 'stomach' at a nearby fertiliser plant.

The anaerobic digester heats the food, traps its methane gas and feeds the energy into the electricity grid, powering up to 3,000 homes.
"Food waste really shouldn't be thought of as a waste, it should be thought of as a resource," said the city's waste education officer, Clare Courtauld.
"It's really important to take food waste out of landfill because it produces harmful greenhouse gases.

"If global food waste was a country, it would actually be the third-highest greenhouse gas emitter in the world."

Food scraps are fed to the mechanical stomach around the clock. (Flickr: Taz, CC BY 2.0)
Ms Courtauld said the City had so far recycled 43 tonnes of food waste and saved 81,000 kilograms of CO2 equivalent gasses that would have otherwise entered the atmosphere rotting in landfill.

The $8 million mechanical stomach sits at the Jandakot headquarters of fertiliser company RichGro.

It was the first bio-waste plant of its kind to operate in the southern hemisphere when it opened in 2016.
"We're mechanically replicating a stomach, whether it be a cow's stomach or a human stomach," RichGro managing director Tim Richards said.
"Their trucks come in … they tip off the food waste.

"It then goes through a piece of machinery which removes any packaging that might be in with the food waste and any contamination.

"It pulps the food waste up into like a porridge consistency and doses it into a big tank.

The food waste is pulped into a rich slurry and pumped into the digester. (ABC News: Gian De Poloni)

"This tank then feeds the two digesters … they're getting fed 24 hours a day.

"As it breaks down, it generates methane gas. We're capturing that gas and we're running large generators that combined can produce up to 2.4 megawatts of electricity."

The plant powers the company's entire operations and up to 3,000 neighbouring homes, all from food waste.

What goes in, must come out

"Out the back end comes a liquid that is actually certified organic as a liquid fertilizer," Mr Richards said.

"We sell a percentage of that to farmers and the remaining percentage of it we add into our compost piles."

The bioenergy plant converts the methane gas from food waste into electricity to feed into the local power grid. (ABC News: Gian De Poloni)

Some foods are better than others.
"It's a bit like the doctors tell us to eat a balanced diet. I need to feed it a balanced diet as well," Mr Richards said.
"Certainly, you can overdo a good thing — you wouldn't want too much fats, oils and greases.

"A lot of fruit and vege, starchy, sugary products are good. They produce a lot of energy."

Seafood waste is also collected from a business in Hamilton Hill. (ABC News: Gian De Poloni)

The City's waste manager, Lyall Davieson, said there was community appetite for these sorts of initiatives.

"I've been in waste for about 25 years," he said.

"Not so long ago, all we could really do was just recycle a few cans and a bit of steel.

"But now we really have at our disposal lots of options to divert waste from landfill and to recycle."

The energy created from food waste is fed into the existing electricity grid, powering up to 3,000 homes. (ABC News: Gian De Poloni)

Frank Scarvaci, who owns a longstanding independent supermarket in Hamilton Hill, was one of the first businesses to sign up for the service.

He said it was a natural progression for his grocery store after embracing a plastic bag ban and installing solar power.

"I've been surprised [at] how the community has accepted the change," he said.

"I thought [there] was going to be much more resistance in regards to when they scrapped plastic bags, for example — but there was virtually no resistance at all."

Contamination causes indigestion

While common in Europe, the plant is just one of a few of its kind to be built in Australia.

People living close to the plant in Perth's southern suburbs wouldn't even know their homes are being powered by food waste. (ABC News: Gian De Poloni)

The City of Cockburn said it was not a waste service it would expand to households, because the risk of contamination disrupting the process was too high.

"We do have a machine that does have a certain ability to remove a level of the contamination," Mr Richards said.

"Can it remove everything? No, it can't.

"We've even had bowling balls come through — you can't process things like that, in a system like this. It does damage our machinery."

Bio-energy has a bright future

The bio-energy technology is growing in Australia, with the next logical step in the process to convert the bio-waste into biomethane, which could be fed into the gas grid.

The Federal Government is co-funding a biomethane production facility at a wastewater treatment plant in Sydney's southern suburbs.

Once online in 2022, the $14 million plant is expected to pump biomethane derived from biogas created by a similar 'mechanical stomach' that would meet the gas needs of more than 13,000 homes.

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(AU) Narooma’s Hot Spot Of Ocean Warming Is More Than Three Times The Global Average

University of NSW -  Diane Nazaroff

A UNSW analysis has found waters off Sydney, southern NSW and eastern Tasmania are demonstrating an accelerated warming trend.

Extraordinary water temperatures of up to 24 degrees were recorded off the coast of Narooma in January. Image: Shutterstock.

The waters off southern NSW and the east coast of Tasmania are warming twice as fast as waters off northern NSW, and at more than three times the global average, a UNSW study has found.

The study, published in Geophysical Research Letters, analysed how coastal waters adjacent to the Eastern Australian Current (EAC) have warmed over the last 25 years.

Scientists have so far found that parts of western boundary currents such as the EAC, which runs along the east coast of Australia, are warming at two to three times the global average of 0.12 degrees per decade.

The UNSW study found that the coastal warming rates at Coffs Harbour (0.16 degrees per decade, and North Stradbroke Island 0.22 degrees per decade) were lower than the EAC rate.

But the study found the warming rate was high at Maria Island off Tasmania (0.41 degrees per decade) and highest off Sydney and Narooma (both 0.48 degrees per decade).

This means these waters have warmed about 1.5 degrees on average in the past 30 years.

“What really surprises me is the raw numbers and the effect of climate change, what half a degree per decade actually means for an ecosystem or for an environment in 10 or 20 years,” lead author and Postdoctoral Research Fellow in UNSW Science’s School of Mathematics and Statistics, Dr Neil Malan, says.

“These numbers are accelerating off southern NSW: at times this year the water temperature there was four degrees warmer than normal.

“The fact that the trend is so large, and that it’s more than three times greater than the global average and that Narooma is such a hotspot, is very shocking.”

Graphic shows warming per decade in East Australian coastal waters in the last 25 years.

Dr Malan says this ‘tropicalisation of ecosystems’ could have a widespread biological impact.

Referring to a 2016 Macquarie University study, he says it will make life difficult for species such as the penguins of Montague Island.

The study on the foraging efficiency of the penguins found that warmer ocean temperatures affect penguins’ ability to hunt and catch prey.

“Their work seems to show that they avoid the warm water so they swim longer distances to find these lower temperature areas to find food,” he says.

The UNSW study used data from over 10 years of measurements of actual water temperatures from five sites (North Stradbroke Island, Coffs Harbour, Sydney, Narooma and Maria Island); satellite estimates of temperatures and currents and a regional ocean model over the last 22 years.

Dr Malan says fast-flowing western boundary currents, like the EAC, bring the impacts of changes of ocean basin circulation (in this case across the breadth of the south Pacific Ocean) to their coastlines, which are usually highly populated.

Dr Neil Malan. Image: Supplied.

The EAC moves warm water down the coast of NSW, but just north of Sydney it branches off towards New Zealand.

At this point it forms large eddies (rotating bodies of warm ocean water) that are carried along SE Australia.

 Another UNSW study has showed that the amount of warm water transported south by these eddies is increasing.

Dr Malan says the EAC has some of the strongest currents and eddies in the world.

“Northern NSW water temperatures, while still warming, are more stable as they are not as affected by what is happening offshore. It is southern NSW, where we see an increase in eddy activity, that is warming the fastest,” he says.

Dr Malan says the next areas of research will look at longer trends of coastal warming dating back to the 1950s; studying more coastal sites around Australia; and looking at the link between deep ocean and coastal water temperatures.

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