{"id":204193,"date":"2021-03-16T16:30:45","date_gmt":"2021-03-16T13:30:45","guid":{"rendered":"https:\/\/en.buradabiliyorum.com\/electricity-has-become-a-jigsaw-and-coal-is-unable-to-provide-the-missing-pieces\/"},"modified":"2021-03-16T16:30:45","modified_gmt":"2021-03-16T13:30:45","slug":"electricity-has-become-a-jigsaw-and-coal-is-unable-to-provide-the-missing-pieces","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/electricity-has-become-a-jigsaw-and-coal-is-unable-to-provide-the-missing-pieces\/","title":{"rendered":"#Electricity has become a jigsaw and coal is unable to provide the missing pieces"},"content":{"rendered":"

“#Electricity has become a jigsaw and coal is unable to provide the missing pieces<\/strong>”<\/p>\n

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There’s something the energy minister said when they announced the early closure of Victoria’s second-biggest coal-fired power station last week that was less than complete.<\/p>\n

Yallourn, in the Latrobe Valley, provides up to 20%<\/a> of Victoria’s power. It has been operating for 47 years<\/a>. Since late 2017 at least one of its four units has broken down 50 times<\/a>. Its workforce doubles<\/a> for three to four months most years to deal with the breakdowns. It pumps out 3%<\/a> of Australia’s carbon emissions.<\/p>\n

On Wednesday Energy Australia gave seven years notice of its intention to close it in mid-2028<\/a>, four years earlier than previously announced, a possibility for which regulators had been preparing<\/a>.<\/p>\n

In what might have been a rhetorical flourish, Energy Minister Angus Taylor warned of “price spikes every night when the sun goes down<\/a>“.<\/p>\n

Then he drew attention to what had happ<\/a>ened when two other coal-fired power stations closed down \u2014Victoria’s Hazelwood and South Australia’s Northern (South Australia’s last-remaining coal-fired generator).<\/p>\n

He said “wholesale prices skyrocketed by 85%<\/a>“.<\/p>\n

And there he finished, without going on to detail what really mattered. South Australia and Victoria now have the lowest<\/a> wholesale power prices in the National Electricity Market\u2014that’s right, the lowest.
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Coal-fired plants close, then prices fall<\/b><\/p>\n

Before Northern closed, South Australia had Australia’s highest<\/a> price.<\/p>\n

Five years after the closure of Northern in 2016, and four years after the closure of Hazelwood in 2017, South Australia and Victorian have wholesale prices one-third<\/a> lower than those in NSW and two-fifths<\/a> lower than those in Queensland.<\/p>\n

Something happened after the closure (largely as a result of the closure) that forced prices down.<\/p>\n

South Australia became a renewables powerhouse.<\/p>\n

The Australian National University’s Hugh Saddler<\/a> points out that renewable-sourced power\u2014wind and grid solar\u2014now accounts for 62% of power supplied to the South Australian grid, and at times for all<\/a> of it.<\/p>\n

Much of it is produced near Port Augusta, where the Northern and Playford coal-fired power stations used to be, because that’s where the transmission lines begin.<\/p>\n

Being even cheaper than the power produced by the old brown-coal-fired power stations, there is at times so much it that it sends prices negative<\/a>, meaning generators get paid to turn off in order to avoid putting more power into the system than users can take out.<\/p>\n

It’s one of the reasons coal-fired plants are closing: they are hard to turn off. They are just as hard to turn on, and pretty hard to turn up. <\/p>\n

Coal can’t respond quickly<\/b><\/p>\n

There are times (when the wind doesn’t blow and there’s not much sun, such as last Friday<\/a> in South Australia) when prices can get extraordinarily high.<\/p>\n

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\n South Australian wind projects congregate around power lines. Credit: AEMO<\/a>
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But coal-fired plants, especially brown-coal-fired plants such as Victoria’s Hazelwood and Yallourn and Victoria’s two remaining big plants, Loy Yang A and B, are unable to quickly ramp up to take advantage of them.<\/p>\n

Although “dispatchable<\/a>” in the technical meaning of the term used by the minister, coal-fired stations can’t fill gaps quickly.<\/p>\n

Batteries can respond instantly to a loss of power from other sources (although not for very long), hydro can respond in 30<\/a> to 70<\/a> seconds, gas peaking plants can respond within minutes<\/a>.<\/p>\n

But coal can barely move. As with nuclear power, coal-fired power needs to be either on (in which case it can only slowly ramp up) or off, in which case turning it on from a standing start would be way too slow.<\/p>\n

What was a feature is now a bug<\/b><\/p>\n

That’s why coal-fired generators operate 24-7, to provide so-called base-load, because they can’t really do anything else.<\/p>\n

Brown coal generators are the least dispatchable. Brown coal is about 60% water<\/a>. To make it ignite and keep boiling off the water takes sustained ultra-high temperatures. Units at Yallourn have to keep burning coal at high output (however low or negative the prices) or turn off. <\/p>\n

In the days when the other sources of power could be turned on and off at will, this wasn’t so much of a problem. <\/p>\n

Hydro or gas could be turned on in the morning when we turned on our lights and heaters and factories got down to business, and coal-fired power could be slowly ramped up.<\/p>\n

At night, when there was less demand for coal-fired power, some could be created by offering cheap off-peak water heating.<\/p>\n

But those days are gone. Nationwide, wind and solar including rooftop solar supplies 20%<\/a> of our needs. It turns on and off at will. <\/p>\n

Wind often blows strongly at night. What was a feature of coal\u2014its ability to provide steady power rather than fill gaps\u2014has become a bug.<\/p>\n

Gas and batteries can fill gaps coal can’t<\/b><\/p>\n

It’s as if our power system has become a jigsaw with the immovable pieces provided by the wind and the sun. It’s our job to fill in the gaps. <\/p>\n

To some extent, as the prime minister<\/a> says, gas will be a transition fuel, able to fill gaps in a way that coal cannot. But gas has become expensive, and batteries are being installed everywhere.<\/p>\n

Energy Australia plans to replace its Yallourn power station with Australia’s first four-hour utility-scale battery<\/a> with a capacity of 350 megawatts, more than any battery operating in the world today. South Australia is planning an even bigger one, up to 900 megawatts<\/a>.<\/p>\n

Australia’s Future Fund and AGL Energy are investing $2.7 billion<\/a> in wind farms in NSW and Queensland which will fill gaps in a different way\u2014their output peaks at different times to wind farms in South Australia and Victoria. <\/p>\n

Filling the gaps won’t be easy, and had we not gone down this road there might still have been a role for coal, but the further we go down it the less coal can help.<\/p>\n

As cheap as coal-fired power is, it is being forced out of the system by sources of power that are cheaper and more dispatchable. We can’t turn back.\n <\/p>\n\n

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Up to 90% of electricity from solar and wind the cheapest option by 2030\n <\/p><\/div>\n

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\n The Conversation
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\n This article is republished from The Conversation<\/a> under a Creative Commons license. Read the original article<\/a>.\"The<\/p>\n

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\n Electricity has become a jigsaw and coal is unable to provide the missing pieces (2021, March 16)
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