- Date published:
8:22 am, November 30th, 2020 - 25 comments
Categories: australian politics, climate change, Environment, science, uncategorized - Tags: bushfires, electricity, electricity market, pumped hydro
Australia is likely to have less of an issue with raging bush fires this year. La Niña is likely to give a break to the droughts with a wetter East Coast. Doesn’t stop record heatwaves as is happening at present. Means that there are more grass fires than there were when grass wasn’t growing. And there is still a lot of bush to burn. Dozens of fires burning across NSW as cool change hits Sydney
This is pretty much the pattern that expected and long predicted with climate change. Everything involved with climate gets more extreme over time – especially in a continental climate like Australia. Even the short range predictions like the one from a week ago turn out to be somewhat less than what happens.
None of this is particularly interesting to me. It has been increasingly predictable to anyone who has been looking at the developing theory and data around greenhouse gases since my earth sciences undergraduate degree back in the later 1970s.
Regardless of how much ‘skeptics’ wish to stick their heads up their arse and try to deny they’re rapidly changing the world climate with their actions – it is going to keep happening. Much of the damage has already been done. Even if we stopped pushing greenhouse gases into the atmosphere right now, the effects will continue and keep getting worse for centuries. The trick for the current and coming generations is to limit making it worse.
What was interesting to me, is the current effects on the ecological and human made systems that we rely on. Australia, for instance, is demonstrating the problems of record heatwaves on grass and bush fires. It is also showing up weaknesses in their power grids. There is an accessible article at ABC “Electricity supplies under pressure due to heatwave, energy market operator warns” which explains the effects. Many of which we will see here.
The biggest impact on electricity demand, by far, is from air conditioners.
In Adelaide and Melbourne, demand could double in a heatwave due to air conditioning, Mr Skinner said.
“At about 7:00pm or 8:00pm on a typical Victorian weekday, the demand would be about 5,000 megawatts; on an absolute extreme stinker of a day, maybe 43 degrees or something, it would be around 9,500 megawatts. That’s huge.
“So more than half of the electricity will be going through an air conditioner, and then if the wind turns around the next day, all of those air conditioners will be off.”ABC: “Electricity supplies under pressure due to heatwave, energy market operator warns“
While it is cooler here, our electricity market in NZ carries many of the same vulnerabilities. Extreme weather means exactly that. With more accumulated energy sloshing around our atmospheric, ocean, water, and even ice systems – it tends to accentuate effects that we have always had. It just makes them more frequent and/or larger.
Where a heatwave coming in from the tropics or a really nasty icy storm coming up from Antarctica used to be occasional. Now it happens a lot more often because there is more energy pushing them along. Rather than moving on, they are more likely to stall because of running into counteracting weather patterns.
That impacts on the power grids. Especially as we, like Australia, do a steady transition to the cheaper solar and wind technologies on top of our existing hydroelectric and geothermal systems. We need to dump the peak load thermal generation because it causes greenhouse emissions but that often has unexpected issues. For instance…
The job of instantly matching the amount of electricity Australians need with the amount of electricity generators make falls to the AEMO.
“Our role is to be able to forecast demand on the network with a degree of precision,” Mr Gatt said.
It coordinates the dispatching of generators by accepting bids to generate power, and, like any market, when demand is high and supply is tight, prices can go through the roof.
“Base loaders [like coal plants] will tend to bid at a lower price and the peak loaders [like gas plants] will bid at a higher price,” Mr Skinner said.
The first capital to feel the heat this week was Adelaide, which hit 40.6C on Friday — at 7:00pm, the wholesale electricity spot price in South Australia reached $329 per megawatt hour, more than eight times the average price.
“The peaking generators are obviously saying, ‘Well, I’m not getting out of bed until you give me enough money to make it worth my while’,” Mr Skinner said.
South Australia’s normally strong wind resources were only able to provide less than 10 per cent of Friday’s evening peak.
“There’s this unfortunate characteristic in South Australia where on really hot days, the evening peak in electricity demand often occurs with a lull in the wind,” Mr Skinner said.
With little low-cost power available to help keep prices down and interstate electricity imports at their maximum, expensive gas peaking plants set the price.ABC: “Electricity supplies under pressure due to heatwave, energy market operator warns“
Plus of course there are other related issues.
On January 4 this year, Sydney was hit by 42-degree temperatures.
At the same time, bushfires in the Snowy Mountains took out transmission lines connecting New South Wales to Victoria, right when demand was highest.
Electricity spot prices skyrocketed, reaching $14,700 per megawatt hour in NSW late in the day — about 300 times the average wholesale price.ABC: “Electricity supplies under pressure due to heatwave, energy market operator warns“
Here in NZ, we don’t have quite the same need to huddle under out air conditioners. However you can pretty well guarantee that when the weather gets really bad like a tropical store pounding Auckland or and icy blast trying to kill livestock in Southland – that is when our lines and distribution stations will suffer damage.
But then just the sheer absurdities of the engineers – unexpected gremlins.
Despite the AEMO’s best planning and forecasts, not every failure can be predicted.
On December 20 last year, when Melbourne reached 43.5C, a series of wind turbines unexpectedly switched themselves off.
“All of a sudden, over 1,000 megawatts suddenly just tripped out — we went from a system that appeared to be really fat, to having to put out an emergency reserve notice,” Mr Skinner said.
“It got really tight and nearly came to load shedding.”
It turned out the turbines were set to switch off at 40C to protect them from overheating.
“I don’t think even the owners anticipated it,” Mr Skinner said.ABC: “Electricity supplies under pressure due to heatwave, energy market operator warns“
In New Zealand, we have a geographical issue as well. Much of our base load of various types isn’t usefully located. Much of the geothermal and hydrocarbon thermal capacity is in the North Island. Much of the hydro generation is in the South Island. The rationale pattern over the HVDC link is …
If all currently commissioned generation is available, both islands have enough generating capacity at peak times, without the connection between the two islands. However, the HVDC link provides benefits for customers in both the South Island and North Island:
The link provides the South Island consumers with access to the North Island’s thermal generation resources that can support the South Island demand during times of low water storage levels and low inflows to South Island hydroelectric lakes.
The link provides North Island consumers with access to the South Island’s large hydro generation resources that can support the North Island demand at times of peak load.
The link plays an important role in the New Zealand electricity market, and allows North and South Island generators to compete with each other, therefore driving wholesale electricity prices down.Wikipedia: “HVDC Inter-Island – Rationale for the link“
Our generation capacity has and is diversifying especially with the geothermal and the wind capacities offsetting the falls in thermal generation. This reduces the probabilities of single cause effects. It is still overly dependent on localised rainfall and weather effects in both islands.
Plus the lengths of our transmission links causes issues with the flexibility of our grid. A lot of the hydro capacity in particular is in the deep south, well away from the high density populations and industry of the north.
Which is why the pumped hydro systems have started to be investigated about in the electricity sector. $4 billion Lake Onslow pumped hydro scheme could ‘tip electricity market on head’.
Although, I’d have to say that to me doing a lot of smaller pumped hydro projects in the North Island (away from the volcanic plateau) would seem to be to be a more rational idea. You might not get the nature built rock basins. But you would be able to site dams closer to the peak user areas with less of a transmission loss.
After all with the announced closure of Tiwai Point aluminium smelter, thereby releasing 13% of our power generation in the deep south, it seems like there may not be a reason
But I’m sure that the comments will tell me why my thinking is flawed 🙂
BTW: if you want to argue that human caused climate change isn’t happening or will be too minor to worry about – then don’t do it on my post. I’m getting very tired of illiterate dildos who are too lazy to read enough science to be worth arguing with. I will mock you and then ban you. There are other places to argue that – try one of our Open Mike posts. Other criticism of the ideas in this post are welcome.