Archive for the ‘South Australia’ Category
reflections on base load, dispatchable energy and SA’s current situation
Canto: So now we’re going to explore base load. What I think it means is reliable, always available energy, usually from fossil fuel generators (coal oil gas), always on tap, to underpin all this soi-disant experimental energy from solar (but what about cloudy days, not to mention darkness, which is absence of light, which is waves of energy isn’t it?) and wind (which is obviously variable, from calm days to days so stormy that they might uproot wind turbines and send them flying into space, chopping up birds in the process).
Jacinta: Well we can’t think about base load without thinking about grids. Our favourite Wikipedia describes it as ‘the minimal level of demand on an electrical grid over a span of time’. So the idea is that you always need to cover that base, or you’ll be in trouble. And an electrical grid is a provision of electrical service to a particular community, be it a suburb, a city or a state.
Canto: Right, I think, and what I like about Wikipedia is the way it sticks it to the back-facing thinkers, for whom base load always means provision from traditional providers (coal oil gas).
Jacinta: Yes, let’s rub it in by quoting Wikipedia on this.
When the cheapest power was from large coal and nuclear plants which could not be turned up or down quickly, they were used to generate baseload, since it is constant, and they were called “baseload plants.” Large standby reserves were needed in case of sudden failure of one of these large plants. Unvarying power plants are no longer always the cheapest way to meet baseload. The grid now includes many wind turbines which have such low marginal costs that they can bid lower prices than coal or nuclear, so they can provide some of the baseload when the wind blows. Using wind turbines in areas with varying wind conditions, and supplementing them with solar in the day time, dispatchable generation and storage, handles the intermittency of individual wind sources.
Canto: So the times are a-changing with respect to costs and supply, especially as costs to the environment of fossil fuel supplies are at last being factored in, at least in some parts of the world. But let’s keep trying to clarify terms. What about dispatchable generation, and how does it relate to base load?
Jacinta: Well, intermittent power sources, such as wind and solar, are not dispatchable – unless there’s a way to store that energy. Some renewable energy sources, such as geothermal and biomass, are dispatchable, but they don’t figure too much in the mix at present. The key is in the word – these sources are able to be dispatched on demand, and have adjustable output which can be regulated in one way or another. But some sources are easier, and cheaper, to switch on and off than others. It’s much about timing; older generation coal-fired plants can take many hours to ‘fire up’, so their dispatchability, especially in times of crisis, is questionable. Hydroelectric and gas plants can respond much more quickly, and batteries, as we’ve seen, can respond in microseconds in times of crisis, providing a short-term fix until other sources come on stream. Of course, this takes us into the field of storage, which is a whole other can of – what’s the opposite of worms?
Canto: So this question of base load, this covering of ‘minimal’ but presumably essential level of demand, can be a problem for a national grid, but you can break that grid up presumably, going ‘off grid’, which I’m guessing means going off the national grid and either being totally independent as a household or creating a micro-grid consisting of some small community…
Jacinta: Yes and this would be the kind of ‘disruptive economy’ that causes nightmares for some governments, especially conservative ones, not to mention energy providers and retailers. But leaving aside micro-grids for now, this issue of dispatchability can be dealt with in a flexible way without relying on fossil fuels. Energy storage has proven value, perhaps especially with smaller grids or micro-grids, for example in maintaining flow for a particular enterprise. On the larger scale, I suppose the Snowy 2 hydro project will be a big boon?
Canto: 2000 megawatts of energy generation and 175 hours of storage says the online ‘brochure’. But the Renew Economy folks, who always talk about ‘so-called’ base load, are skeptical. They point to the enormous cost of the project, which could escalate, due, among other things, to the difficulties of tunnelling through rock of uncertain quality. They feel that government reports have over-hyped the project and significantly downplayed the value of alternatives, such as battery electric storage systems, which are modular and flexible rather than this massive one-off project which may be rendered irrelevant once completed.
Jacinta: So let’s relate this to the South Australian situation. We’re part of the national grid, or the National Energy Market (NEM), which covers SA and the eastern states. This includes generators, transformers (converting low voltage to high voltage for transport, and then converting back to low voltage for distribution), long distance transmission lines and shorter distance distribution lines. So that’s wholesale stuff, and it’s a market because different companies are involved in producing and maintaining the system – the grid, if you like.
Canto: I’ve heard it’s the world’s largest grid, in terms of area covered.
Jacinta: I don’t think so, but it depends on what metric you use. Anyway, it’s pretty big. South Australia has been criticised by the federal government for somehow harming the market with its renewables push. Also, it was claimed at least a year ago that SA had the highest electricity prices in the world. This may have been an exaggeration, but why are costs so high here? There are green levies on our bill, but I think they’re optional. Also, the electricity system was privatised in the late 90s, so the government has lost control of pricing. High-voltage transmission lines are owned by ElectraNet, part-owned by the Chinese government. The lower voltage distribution lines are operated by SA Power Networks, majority-owned by a Hong Kong company, and then there are the various private retailers. It’s hard to work out, amongst all this, why prices are so high here, but the closure of the Northern coal-fired power station in Port Augusta, which was relatively low cost and stable, meant a greater reliance on more expensive gas. Wind and solar have greater penetration into the SA network than elsewhere, but there’s still the intermittency problem. Various projects currently in the pipeline will hopefully provide more stability in the future, including a somewhat controversial interconnector between SA and NSW. Then there’s the retail side of things. Some retailers are also wholesalers. For instance AGL supplies 48% of the state’s retail customers and controls 42% of generation capacity. All in all, there’s a lack of competition, with only three companies competing for the retail market, which is a problem for pricing. At the same time, if competitors can be lured into the market, rather than being discouraged by monopoly behaviour, the high current prices should act as an incentive.
Jacinta: I don’t know about that, but before the Tesla battery came online the major gas generators – who are also retailers – were using their monopoly power to engage in price gouging at times of scarcity, to a degree that was truly incredible – more so in that it was entirely legal according to the ACCC and other market regulators. The whole sorry story is told here . So I’m hoping that’s now behind us, though I’m sure the executives of these companies will have earned fat bonuses for exploiting the situation while they could.
Canto: So prices to consumers in SA have peaked and are now going down?
Jacinta: Well the National Energy Market has suffered increased costs for the past couple of years, mainly due to the increased wholesale price of gas, on which SA is heavily reliant. It’s hard to get reliable current data on this online, but as of April this year the east coast gas prices were on their way down, but these prices fluctuate for all sorts of reasons. Of course the gas lobby contends that increased supply – more gas exploration etc – will solve the problem, while others want to go in the opposite direction and cut gas out of the South Australian market as much as possible. That’s unlikely to happen though, in the foreseeable, so we’re likely to be hostage to fluctuating gas prices, and a fair degree of monopoly pricing, for some time to come.
more on Australia’s energy woes and solutions
the SA Tesla Powerpack, again
Canto: So the new Tesla battery is now in its final testing phase, so South Australia can briefly enjoy some fame as having the biggest battery in the world, though I’m sure it’ll be superseded soon enough with all the activity worldwide in the battery and storage field.
Jacinta: Well I don’t think we need to get caught up with having the biggest X in the world, it’s more important that we’re seen as a place for innovation in energy storage and other matters energetic. So, first, there’s the Tesla battery, associated with the Hornsdale wind farm near Jamestown, and there are two other major battery storage systems well underway, one in Whyalla, designed for Whyalla Steel, to reduce their energy costs, and another smaller system next to AGL’s Wattle Point wind farm on Yorke Peninsula.
Canto: Well, given that the federal government likes to mock our Big Battery, can you tell me how the Tesla battery and the other batteries work to improve the state?
Jacinta: It’s a 100MW/129MWh installation, designed to serve two functions. A large portion of its stored power (70MW/39MWh) is for the state government to stabilise the grid in times of outage. Emergency situations. This will obviously be a temporary solution before other, slower reacting infrastructure can be brought into play. The rest is owned by Neoen, Tesla’s partner company and owner of the wind farm. They’ll use it to export at a profit when required – storing at low prices, exporting at higher prices. As to the Whyalla Steel battery, that’s privately owned, but it’s an obvious example, along with the AGL battery, of how energy can be produced and stored cleanly (Whyalla Steel relies on solar and hydro). They point the way forward.
Canto: Okay here’s a horrible question, because I doubt if there’s any quick ‘for dummies’ answer. What’s the difference between megawatts and megawatt-hours?
Jacinta: A megawatt, or a watt, is a measure of power, which is the rate of energy transfer. One watt equals one joule per second, and a megawatt is 1,000,000 watts, or 1,000 kilowatts. A megawatt-hour is one megawatt of power flowing for one hour.
Canto: Mmmm, I’m trying to work out whether I understand that.
Jacinta: Let’s take kilowatts. A kilowatt (KW) is 1,000 times the rate of energy transfer of a watt. In other words, 1000 joules/sec. One KWh is one hour at that rate of energy transfer. So you multiply the 1000 by 3,600, the number of seconds in an hour. That’s a big number, so you can express it in megajoules – the answer is 3.6Mj. One megajoule equals 1,000,000 joules of course.
Canto: Of course. So how is this working for South Australia’s leadership on renewables and shifting the whole country in that direction?
Genex Power site in far north Queensland – Australia’s largest solar farm together with a pumped hydro storage plant
Jacinta: Believe me it’s not all South Australia. There are all sorts of developments happening around the country, mostly non-government stuff, which I suppose our rightist, private enterprise feds would be very happy with. For example there’s the Genex Power solar, hydro and storage project in North Queensland, situated in an old gold mine. Apparently pumped hydro storage is a competitor with, or complementary to, battery storage. Simon Kidston, the Genex manager, argues that many other sites can be repurposed in this way.
Canto: And the cost of wind generation and solar PV is declining at a rate far exceeding expectations, especially those of government, precisely because of private enterprise activity.
Jacinta: Well, mainly because it’s a global market, with far bigger players than Australia. Inputs into renewables from states around the world – India, Mexico, even the Middle East – are causing prices to spiral down.
Canto: And almost as we speak the Tesla gridscale battery has become operational, and we’ve gained a tiny place in history. But what about this National Energy Guarantee from the feds, which everyone seems to be taking a swing at. What’s it all about?
Jacinta: This was announced a little over a month ago, as a rejection of our chief scientist’s Clean Energy Target. Note how the Feds again avoid using such terms as ‘clean’ and ‘renewable’ when it talks or presents energy policy. Anyway, it may or may not be a good thing – there’s a summary of what some experts are saying about it online, but most are saying it’s short on detail. It’s meant to guarantee a reliable stream of energy/electricity from retailers, never mind how the energy is generated – so the government can say it’s neither advocating nor poo-pooing renewables, it’s getting out of the way and letting retailers, some of whom are also generators, deliver the energy from whatever source they like, or can.
Canto: So they’re putting the onus on retailers. How so?
Jacinta: The Feds are saying retailers will have to make a certain amount of dispatchable power available, but there is one ridiculously modest stipulation – greenhouse emissions from the sector must be reduced by 26% by 2030. The sector can and must do much better than that. The electricity sector makes up about a third of emissions, and considering the slow movement on EVs and on emissions reductions generally, we’re unlikely to hold up our end of the Paris Agreement, considering the progressively increasing targets.
Canto: But that’s where they leave it up to the private sector. To go much further than their modest target. They would argue that they’re more interested in energy security.
Jacinta: They have a responsibility for providing security but not for reducing emissions? But it’s governments that signed up to Paris, not private enterprises. The experts are pointing this out with regard to other sectors. More government-driven vehicle emission standards, environmental building regulations, energy efficient industries and so forth.
Canto: And the Feds actually still have a renewable energy agency (ARENA), in spite of the former Abbott government’s attempt to scrap it, and a plan was announced last month to set up a ‘demand response’ trial, involving ARENA, AEMO (the energy market operator) and various retailers and other entities. This is about providing temporary supply during peak periods – do you have any more detail?
Jacinta: There’s a gloss on the demand response concept on a Feds website:
From Texas to Taiwan, demand response is commonly used overseas to avoid unplanned or involuntary outages, ease electricity price spikes and provide grid support services. In other countries, up to 15 per cent of peak demand is met with demand response.
Canto: So what exactly does it have to do with renewables?
Jacinta: Well get ready for a long story. It’s called demand response because it focuses on the play of demand rather than supply. It’s also called demand management, a better name I think. It’s partly about educating people about energy not being a finite commodity available at all times in equal measure…
Canto: Sounds like it’s more about energy conservation than about the type of energy being consumed.
Jacinta: That’s true. So on extreme temperature days, hot or cold – but mostly hot days in Australia – electricity demand can jump by 50% or so. To cope with these occasional demand surges we’ve traditionally built expensive gas-based generators that lie idle for most of the year. For reasons I’m not quite able to fathom, at such extreme demand times the ‘spot price’ for wholesale electricity goes through the roof – or more accurately it hits the ceiling, set by the National Energy Market at $14,000 per MWh. That’s just a bit more than the usual wholesale price, about $100/MWh. Demand management is an attempt to have agreements with large commercial/industrial users to reduce usage at certain times, or the agreements could be with energy retailers who then do deals with customers. Of course, bonuses could be handed out to compliant customers. The details of how this offsets peak demand usage and pricing are still a bit of a mystery to me, however.
The battle for justice, part 1: some background to the case
A prosecution should not proceed if there is no reasonable prospect of a conviction being secured. This basic criterion is the cornerstone of the uniform prosecution policy adopted in Australia.
from ‘The decision to prosecute’, in ‘Statement of prosecution policy and guidelines’, Director of Public Prosecutions, South Australia, October 2014
not this movie, unfortunately
I rarely focus on myself on this blog, but now I feel I have to. Today I lost my job because of something that happened to me about 12 years ago. So the next I don’t know how many posts will be devoted to my battle for justice, in the hope that it may help others in a similar situation. Of course I also find that writing is my best solace, as well as my best weapon. I have no financial resources to speak of, all I have is a certain amount of nous.
Between 2003-4 and 2010 I was a foster carer, under the aegis of Anglicare. Over that period I fostered six boys, with naturally varying success.
So why did I become a foster carer? I simply saw an ad on a volunteering website. I was being pushed to do some work, which I’ve always been reluctant to do, being basically a reclusive bookworm who loves to read history, science, everything that helps to understand what humans are, where they came from, where they’re going. And I hate when work interferes with that! But having come from what for me was a rather toxic family background, trying to shut myself from screaming fights between parents, and being accused by my mother, the dominant parent, of being a sneak and a liar, and ‘just like your father’ (her worst insult), and being physically and mentally abused by both parents (though never sexually), and having run away from home regularly in my teen years, I imagined that, as a survivor, I could offer something which might work for at least some of these kids – a hands-off, non-bullying environment which would be more equal in terms of power than many foster-care situations. Call me naive…
Mostly, this approach worked. I did have to get heavy now and then of course, but not for long, so I always managed to stay on good terms with my foster-kids, as I have more recently with my students. This was even the case with the lad who accused me of raping him.
Let me describe the case as briefly as possible. A fifteen-year old boy was in my care in September 2005. He was much more of a handful than the previous two boys I’d looked after, and when I lost my temper with him during a school holiday trip in Victor Harbour, he took it out on me by claiming to his mother, with whom he spent his weekends, that I’d punched him on the back of the head. This was false, but his mother took the matter to the police, and the boy was immediately taken out of my care.
After an internal review conducted by Anglicare I was cleared of any wrongdoing, to their satisfaction at least, and another boy was placed in my care. Then, sometime in early 2006, this boy was secretly whisked out of my care, and I was informed by Anglicare that a serious allegation had been made against me. I was in shock, naturally thinking this new boy had also accused me of some kind of violence, but I was finally informed by the Anglicare social worker who’d been overseeing my placements that ‘it isn’t your new foster – kid’. The penny dropped more or less immediately that it was the same boy who’d accused me of hitting him. This boy, as far as I was aware, was now living happily with his mum.
I was left in limbo for some time, but eventually I received a message from the police to go to the Port Adelaide police station. There I was asked to sit down in an office with two police officers, and informed that I was under arrest for rape.
I was somewhat taken aback haha, and I don’t recall much of the conversation after that, but I think it went on for a long time. I do remember one key question: if the boy’s lying, why would he make such an allegation? I had no answer: I was unable to think clearly, given the situation. But later that night, after my release on bail, an answer came to me, which might just be the right one. When the boy was in my care, the plan was to reconcile him with his mother, who put him in care in the first place because she couldn’t cope with him. I knew his mother, as I met her every weekend for handover. She was highly strung and nervous, and it seemed likely she was again having trouble coping with full-time care. Quite plausibly, she was threatening to return him to foster care, which he wouldn’t have wanted. She allowed him to smoke, she allowed him to hang out with his mates, and her environment was familiar to him. To him, I would’ve seemed boringly bookish and unadventurous. What’s more, his claim that I’d hit him had worked perfectly for him, getting him exactly where he wanted. Why not shut the door on foster care forever, by making the most extreme claim?
I don’t really know if this sounds preposterous to an impartial reader, but this answer to the riddle struck me as in keeping with what I knew of the boy’s thinking, and it was backed up by a remark he made to me, which soon came back to haunt me. He said ‘my mum’s friend told me that all foster carers are child molesters…’. It was the kind of offhand remark he’d often make, but it was particularly striking in light of something I was told later by my lawyer. Apparently, the boy didn’t tell his mother directly that I’d raped him, he’d told a friend of his mother, who’d then told her.
So, after the sleepless night following my arrest, I felt confident that I knew the answer to the key police question. I typed it up and took it forthwith to the Port Adelaide station (I didn’t trust the mail). How utterly naive of me to think they’d be grateful, or interested! I received no response.
So I obtained a lawyer through legal aid, or the Legal Services Commission. At the time I was dirt poor: I’d received a stipend as a foster carer, but that had stopped. Otherwise I worked occasionally as a community worker or English language teacher, mostly in a voluntary role. From the moment I was charged I spent many a sleepless night imagining my days in court, heroically representing myself of course, exposing contradictions and confabulations, citing my spotless record, my abhorrence of violence of all kinds, etc, etc. So I was a bit miffed when my lawyer told me to sit tight and do nothing, say nothing, and to leave everything to him. Standard procedure, presumably. The case passed from hearing to hearing (I don’t know if that’s the word – at least there were several court appearances), over a period of more than a year, and every time I expected it to be dismissed, since I knew there was no evidence. It had to be dismissed, there could be no other possibility. The only reason it had become a court matter in the first place, it seemed to me, was the absolute enormity of the allegation. But how could this possibly be justified? But I had to admit, the boy had, more or less accidentally, stumbled on the perfect crime to accuse me of – a crime committed months before, where there could be no visible evidence one way or another… It was all very nerve-wracking. And I was very annoyed at the fact that the DPP (the Office of the Director of Public Prosecutions) seemed to have different lawyers representing it at every court appearance, and mostly they behaved as if they’d only been handed the brief minutes before.
Finally I arrived at the lowest point so far – an arraignment. I didn’t know this (my last) appearance would be an arraignment and I didn’t know what that was. I just expected yet another appearance with a handful of yawning court officials and lawyers in attendance. Instead I found a packed courtroom.
Arraignment is a formal reading of a criminal charging document in the presence of the defendant to inform the defendant of the charges against him or her. In response to arraignment, the accused is expected to enter a plea.
In Australia, arraignment is the first of eleven stages in a criminal trial, and involves the clerk of the court reading out the indictment. (WIKIPEDIA)
The reason the courtroom was packed is that several arraignments are processed in the same courtroom on the same day, so there were several accused there with their friends and families. Unfortunately, I was solo. On my turn, I was taken out to the holding cells and brought in – some kind of ceremonial – to the dock. The charge was read out (I’d already been given the ‘details’ by the lawyer, so I barely listened to it) and I was asked to plead, and the judge told the court, to my utter amazement, that I was adjudged to have a case to answer.
So it was perhaps even more amazing that, a week or two after that appearance, the case was dropped.
the SA government’s six-point plan for energy security, in the face of a carping Federal government
South Australian Premier Jay Weatherill, right, with SA Energy Minister Tom Koutsantonis
The South Australian government has a plan for energy, which you can take a look at here. And if you’re too lazy to click through, I’ll summarise:
- Battery storage and renewable technology fund: Now touted as the world’s largest battery, this will be a storage facility for wind and solar energy, and if it works, it will surely be a major breakthrough, global in its implications. The financing of the battery (if we have to pay for it!) will come from a new renewable energy fund.
- New state-owned gas power plant: This will be a 250 MW capacity gas powered facility designed initially for emergency use, and treated as a future strategic asset when (and if) greater energy stability is achieved at the national level. In the interim the state government will (try to?) work with transmission and distribution companies to provide 200 MW of extra generation in times of peak demand.
- Local powers over the national market: The government will legislate for strong new state powers for its Energy Minister as a last-resort measure to enable action in South Australia’s best interests when in conflict with the national market. In addition, all new electricity-generation projects above 5 MW will be assessed as to their input into the state electricity system and its security.
- New generation for more competition: The SA Government will use its own electricity contract (for powering schools, hospitals and government services) to tender for more new power generators, increasing competition in the market and putting downward pressure on prices.
- South Australian gas incentives: Government incentives will be given for locally-sourced gas development (we have vast untapped resources in the Cooper Basin apparently) so that we can replace all that dirty brown coal from Victoria.
- Energy Security Target: This new target, modelled by Frontier Economics, will be designed to encourage new investments in cleaner energy, to increase competition and put downward pressure on prices. The SA government will continue to advocate for an Emissions Intensity Scheme (EIS), contra the Federal government. It’s expected that the Energy Security Target will morph into an EIS over time – depending largely on supportive national policy. Such a scheme is widely supported by industry and climate science.
It’s an ambitious plan perhaps but it’s definitely a plan, and definitely actionable. The battery storage part is of course generating a lot of energy already, both positive and negative, as pioneering projects tend to do. I’m very much looking forward to December’s unveiling. Interestingly, in this article from April this year, SA Premier Jay Weatherill claimed 90 expressions of interest had been received for building the battery. Looks like they never stood a chance against the mighty Musk. In the same article, Weatherill announced that the expression of interest process had closed for the building of SA’s gas power plant, point two of the six-point plan. Thirty-one companies from around the world have vied for the project, apparently. And as to point three, the new powers legislation was expected to pass through parliament on April 26. Weatherill issued a press release on the legislation in late March. Thanks to parliamentary tracking, I’ve found that the bill – called the Bill to Amend the Emergency Management (Electricity Supply Emergencies) Act – was passed into law by the SA Governor on May 9.
Meanwhile, two regional projects, one in the Riverland and another in the north of SA, are well underway. A private company called Lyon Group is building a $1 billion battery and solar farm at Morgan, and another smaller facility, named Kingfisher, in the north. In this March 30 article by Chris Harmsen, a spokesperson for Lyon Group said the Riverland project, Australia’s largest solar farm, was 100% equity financed (I don’t know what that means – I’ll read this later) and would be under construction within months. It will provide 300MW of storage capacity. The 120 MW Kingfisher project will begin construction in September next year. Then there’s AGL’s 210MW gas-fired power station on Torrens Island, mentioned previously. It’s worth noting that AGL’s Managing Director Andy Vesey spoke of the positive investment climate created by the SA government’s energy plans.
So I think it’s fair to say that in SA we’re putting a lot of energy into energy. Meanwhile, the Federal Energy minister, Josh Frydenberg, never speaks positively about SA’s plans. Presumably this is because SA’s government is on the other side of the political divide. You can’t say anything positive about your political enemies because they might stop being your enemies, and then what would you do? The identity crisis would be intolerable.
I’ve written about macho adversarial systems in politics, law and industrial relations before. Frydenberg, as the Federal Minister, must be well aware of SA’s six-point plan (found with a couple of mouse-clicks), and of the plans and schemes of all the other state governments, otherwise he’d be massively derelict in his duty. Yet he’s pretty well entirely dismissive of the Tesla-Neoen deal, and describes the other SA initiatives, pathetically, as ‘an admission of failure’. It seems almost a rule with the current Feds that you don’t mention renewable, clean energy positively and you don’t mention the SA government’s initiatives in the energy field except negatively. Take for example Frydenberg’s reaction to recent news that the Feds are consulting with the car industry on reducing fuel emissions. He brought up the ‘carbon tax’ debacle (a reference to the former Gillard government’s 2012 carbon pricing scheme, repealed by the Abbott government in 2014), declaring that there would never be another one, as if the attempt to reduce vehicle emissions – carbon emissions – had nothing to do with carbon and its reduction, which was what the carbon pricing scheme was all about. This is the artificiality of adversarial systems – where two parties pretend to be further apart than they really are, so that they can engage in the apparently congenial activity of trading insults and holier-than-thou tirades. It’s so depressing. Frydenberg was at pains to point out that the government’s interest in reducing fuel emissions was purely to benefit family economies. It would’ve taken nothing but a bit of honesty and integrity to also say that reduced emissions would be environmentally beneficial. But this apparently would be a step too far.
In my next post I hope to get my head around battery storage technology, and lithium-ion batteries.
References/links
http://ourenergyplan.sa.gov.au/
http://www.abc.net.au/news/2017-04-13/sa-gas-fire-power-station-gains-international-interest/8442578
http://www.abc.net.au/news/2017-04-13/sa-gas-fire-power-station-gains-international-interest/8442578
http://www.abc.net.au/news/2017-03-30/new-solar-project-announced-for-sa-riverland/8400952
http://www.investopedia.com/terms/e/equityfinancing.asp
https://en.wikipedia.org/wiki/Carbon_pricing_in_Australia
South Australia and electricity revisited
Canto: So what’s the latest on SA’s statewide blackout of September 28 last year, who’s to blame, who’s blaming who, and what solutions are in the offing, if any?
Jacinta: Well the preliminary report on the NEM, which we’ve been reading and writing about, has a few things to say about this, and they’re based on the findings of the Australian Energy Market Operator (AEMO) in its own preliminary report.
Canto: He said she said.
Jacinta: Well maybe sort of. So the SA blackout is presented as a case study. Here in SA we have a very high proportion of VRE (variable renewable energy) generation – one of the highest in the world. Our peak demand as a region is 3300 MW, and our supply capacity is almost 2900 MW of gas, almost 1600 MW of wind, and 700 MW of installed solar. We’re connected to the rest of the NEM by two interconnectors, an AC connector with a capacity of 600-650 MW, and a DC connector with a capacity of 220 MW. With electricity demand here declining, or at least not growing, synchronous generation and supply have reduced, with a resultant reduction in system inertia.
Canto: I presume by system inertia you mean the tendency for a machine, a vehicle, or a generator, whatever, a system to keep going once the power’s switched off. Like the QE2 has a lot of system inertia.
Jacinta: Right, but it’s a particularly important term in reference to power generation. There are some neat explanations of this online, but I’ll give a summary here. Coal-fired power stations work through the burning of coal which generates steam to turn a turbine, putting energy into the grid, and being massive, it has a lot of spinning inertia. Slow to fire up, slow to wind down. Solar, though, doesn’t work that way. It has no spinning or even moving parts. When the sun’s off, it’s off, but when it’s on it’s on. There’s really no inertia at all in a conventional solar PV system.
Canto: And wind? That’s the principal renewable energy here.
Jacinta: Yes that has inertia, certainly, but it’s variable and not as significant as perhaps it could be. So anyway on the morning of the blackout weather forecasts were grim, but not enough for AEMO to put out alerts for a ‘credible contingency event’. As it turned out there were at least seven tornadoes in the north of the state that day, as well as numerous lightning strikes and high winds which caused structural damage to transmission lines. At blackout time electricity demand in the state was a little over 1800 MW, with nearly half of it being supplied by wind farms, and of the rest about a third came from gas-fired generators, and the other 600 or so megawatts came through the interconnectors from Victoria. The main Heywood connector was approaching its operating limit. Short circuits to the transmission lines, caused by lightning, were the probable proximal cause of the blackout. Thirteen wind farms were in operation at the time, and eleven of them experienced ‘voltage dips’. What happens in these circumstances is that ‘fault ride-though’ responses are invoked. However, nine of the eleven farms had a lower pre-set limit for the ride-through response to proceed, and after a number of dips those nine wind farms cut their connection. The other two had higher pre-set limits and continued operation.
Canto: Ahh, so those preset limits were set too low?
Jacinta: Maybe – that’s one for further investigation. So the lack of generation from the wind farms caused an overload on the Heywood interconnector, and it was disconnected as per protection systems, resulting in frequency failure on the grid, and blackness fell upon all the land.
Canto: Right, so how did things get restarted? What’s the normal procedure?
Jacinta: Well, there’s this contracted service, called the System Restart Ancillary Service, which in SA is contracted to two major electricity generators (unnamed in the report), who can supposedly restart regardless of the grid situation, and provide power to the transmission network, but these servers failed for unexplained reasons, and power was finally restored through the Heywood interconnector together with the Torrens Island power station.
Canto: Okay, so now the fallout. How could things have been done differently?
Jacinta: Some near-term fixes have been implemented already. Firstly, having to do with frequency rates which I won’t go into here, and secondly in relation to wind farms. Five of them have made changes to their fault ride-through settings, and AEMO is looking at this issue for wind farms across the NEM. The Australian Energy Regulator, another bureaucratic body, will have completed a full analysis of the blackout by early next year to determine if there were any breaches of regulations. Obviously it’ll be looking at the conduct of AEMO throughout, as well as that of the transmission operator, ElectaNet. It’ll also look at these fault ride-though settings of wind farms and the failures of the System Restart Ancillary Service. It all sounds as if everything’s being done that can be done, but the major problem is that grid security as it stands can only be provided by large generators. The report again mentions gas-fired generators as the best solution, at least in the short to medium term.
Canto: So, as the grid, and the general provision of electricity, undergo these transformations, we’ll no doubt experience a few more of these hopefully minor setbacks, which we can learn from as we develop security for a more diverse but more integrated system…
Jacinta: Greater integration might require less squabbling about the future of energy. I can’t see that happening in the near future, unfortunately.