the new ussr illustrated

welcome to the Urbane Society for Skeptical Romantics, where pretentiousness is as common as muck

Posts Tagged ‘electricity

on electrickery, part 2 – the beginnings

leave a comment »

William Gilbert, author of De Magnete, 1600

Canto: So let’s now start at the beginning. What we now call electricity, or even electromagnetism, has been observed and questioned since antiquity. People would’ve wondered about lightning and electrostatic shocks and so forth.

Jacinta: And by an electrostatic shock, you mean the sort we get sometimes when we touch a metal door handle? How does that work, and why do we call it electrostatic?

Canto: Well we could do a whole post on static electricity, and maybe we should, but it happens when electrons – excess electrons if you like – move from your hand to the conductive metal. This is a kind of electrical discharge. For it to have happened you need to have built up electric charge in your body. Static electricity is charge that builds up through contact with clothing, carpet etc. It’s called static because it has nowhere to go unless it comes into contact with a positive conductor.

Jacinta: Yes and it’s more common on dry days, because water molecules in the atmosphere help to dissipate electrons, reducing the charge in your body.

Canto: So the action of your shoes when walking on carpet – and rubber soles are worst for this – creates a transfer of electrons, as does rubbing a plastic rod with wooden cloth. In fact amber, a plastic-like tree resin, was called ‘elektron’ in ancient Greek. It was noticed in those days that jewellery made from amber often stuck to clothing, like a magnet, causing much wonderment no doubt.

Jacinta: But there’s this idea of ‘earthing’, can you explain that?

Canto: It’s not an idea, it’s a thing. It’s also called grounding, though probably earthing is better because it refers to the physical/electrical properties of the Earth. I can’t go into too much detail on this, its complexity is way above my head, but generally earthing an electrical current means dissipating it for safety purposes – though the Earth can also be used as an electrical conductor, if a rather unreliable one. I won’t go any further as I’m sure to get it wrong if I haven’t already.

Jacinta: Okay, so looking at the ‘modern’ history of our understanding of electricity and magnetism, Elizabethan England might be a good place to start. In the 1570s mathematically minded seamen and navigators such as William Borough and Robert Norman were noting certain magnetic properties of the Earth, and Norman worked out a way of measuring magnetic inclination in 1581. That’s the angle made with the horizon, which can be positive or negative depending on position. It all has to do with the Earth’s magnetic field lines, which don’t run parallel to the surface. Norman’s work was a major inspiration for William Gilbert, physician to Elizabeth I and a tireless experimenter, who published De Magnete (On the Magnet – the short title) in 1600. He rightly concluded that the Earth was itself a magnet, and correctly proposed that it had an iron core. He was the first to use the term ‘electric force’, through studying the electrostatic properties of amber.

Canto: Yes, Gilbert’s work was a milestone in modern physics, greatly influencing Kepler and Galileo. He collected under one head just about everything that was known about magnetism at the time, though he considered it a separate phenomenon from electricity. Easier for me to talk in these historical terms than in physics terms, where I get lost in the complexities within a few sentences.

Jacinta: I know the feeling, but here’s a relatively simple explanation of earthing/grounding from a ‘physics stack exchange’ which I hope is accurate:

Grounding a charged rod means neutralizing that rod. If the rod contains excess positive charge, once grounded the electrons from the ground neutralize the positive charge on the rod. If the rod is having an excess of negative charge, the excess charge flows to the ground. So the ground behaves like an infinite reservoir of electrons.

So the ground’s a sink for electrons but also a source of them.

Canto: Okay, so if we go the historical route we should mention a Chinese savant of the 11th century, Shen Kuo, who wrote about magnetism, compasses and navigation. Chinese navigators were regularly using the lodestone in the 12th century. But moving into the European renaissance, the great mathematician and polymath Gerolamo Cardano can’t be passed by. He was one of the era’s true originals, and he wrote about electricity and magnetism in the mid-16th century, describing them as separate entities.

Jacinta: But William Gilbert’s experiments advanced our knowledge much further. He found that heat and moisture negatively affected the ‘electrification’ of materials, of which there were many besides amber. Still, progress in this era, when idle curiosity was frowned upon, was slow, and nothing much else happened in the field until the work of Otto von Guericke and Robert Boyle in the mid-17th century. They were both interested particularly in the properties, electrical and otherwise, of vacuums.

Canto: But the electrical properties of vacuum tubes weren’t really explored until well into the 18th century. Certain practical developments had occurred though. The ‘electrostatic machine’ was first developed, in primitive form, by von Guericke, and improved throughout the 17th and 18th centuries, but they were often seen as little more than a sparky curiosity. There were some theoretical postulations about electrics and non-electrics, including a duel-fluid theory, all of which anticipated the concept of conductors and insulators. Breakthroughs occurred in the 1740s with the invention of the Leyden Jar, and with experiments in electrical signalling. For example, an ingenious experiment of 1746, conducted by Jean-Antoine Nollet, which connected 200 monks by wires to form a 1.6 kilometre circle, showed that the speed of electrical transmission was very high! Experiments in ‘electrotherapy’ were also carried out on plants, with mixed results.

Jacinta: And in the US, from around this time, Benjamin Franklin carried out his experiments with lightning and kites, and he’s generally credited with the idea of positive to negative electrical flow, though theories of what electricity actually is remained vague. But it seems that Franklin’s fame provided impetus to the field. Franklin’s experiments connected lightning and electricity once and for all, though similar work, both experimental and theoretical, was being conducted in France, England and elsewhere.

Canto: Yes, there’s a giant roll-call of eighteenth century researchers and investigators – among them Luigi Galvani, Jean Jallabert, John Canton, Ebenezer Kinnersley, Giovanni Beccaria, Joseph Priestley, Mathias Bose, Franz Aepinus, Henry Cavendish, Charles-Augustin Coulomb and Alessandro Volta, who progressed our understanding of electrical and magnetic phenomena, so that modern concepts like electric potential, charge, capacitance, current and the like, were being formalised by the end of that century.

Jacinta: Yes, for example Coulomb discovered, or published, a very important inverse-square law in 1784, which I don’t have the wherewithal to put here mathematically, but it states that:

The magnitude of the electrostatic force of attraction between two point charges is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them.

This law was an essential first step in the theory of electromagnetism, and it was anticipated by other researchers, including Priestley, Aepinus and Cavendish.

get it?

Canto: And Volta produced the first electric battery, which he demonstrated before Napoleon at the beginning of the 19th century.

Jacinta: And of course this led to further experimentation – almost impossible to trace the different pathways and directions opened up. In England, Humphrey Davy and later Faraday conducted experiments in electrochemistry, and Davy invented the first form of electric light in 1809. Scientists, mathematicians, experimenters and inventors of the early nineteenth century who made valuable contributions include Hans Christian Orsted, Andre-Marie Ampere, Georg Simon Ohm and Joseph Henry, though there were many others. Probably the most important experimenter of the period, in both electricity and magnetism, was Michael Faraday, though his knowledge of mathematics was very limited. It was James Clerk Maxwell, one of the century’s most gifted mathematicians, who was able to use Faraday’s findings into mathematical equations, and more importantly, to conceive of the relationship between electricity, magnetism and light in a profoundly different way, to some extent anticipating the work of Einstein.

Canto: And we should leave it there, because we really hardly know what we’re talking about.

Jacinta: Too right – my reading up on this stuff brings my own ignorance to mind with the force of a very large electrostatic discharge….

now try these..

Advertisements

Written by stewart henderson

October 22, 2017 at 10:09 am

On electrickery, part 1 – the discovery of electrons

leave a comment »

Canto: This could be the first of a thousand-odd parts, because speaking for myself it will take me several lifetimes to get my head around this stuff, which is as basic as can be. Matter and charge and why is it so and all that.

Jacinta: so let’s start at random and go in any direction we like.

Canto: Great plan. Do you know what a cathode ray is?

Jacinta: No. I’ve heard of cathodes and anodes, which are positive and negative terminals of batteries and such, but I can’t recall which is which.

Canto: Don’t panic, Positive is Anode, Negative ICathode. Though I’ve read somewhere that the reverse can sometimes be true. The essential thing is they’re polar opposites.

Jacinta: Good, so a cathode ray is some kind of negative ray? Of electrons?

Canto: A cathode ray is defined as a beam of electrons emitted from the cathode of a high-vacuum tube.

Jacinta: That’s a pretty shitty definition, why would a tube, vacuum or otherwise, have a cathode in it? And what kind of tube? Rubber, plastic, cardboard?

Canto: Well let’s not get too picky. I’m talking about a cathode ray tube. It’s a sealed tube, obviously, made of glass, and evacuated as far as possible. Sciencey types have been playing around with vacuums since the mid seventeenth century – basically since the vacuum pump was invented in 1654, and electrical experiments in the nineteenth century, with vacuum tubes fitted with cathodes and anodes, led to the discovery of the electron by J J Thomson in 1897.

Jacinta: So what do you mean by a beam of electrons and how is it emitted, and can you give more detail on the cathode, and is there an anode involved? Are there such things as anode rays?

Canto: I’ll get there. Early experiments found that electrostatic sparks travelled further through a near vacuum than through normal air, which raised the question of whether you could get a ‘charge’, or a current, to travel between two relatively distant points in an airless tube. That’s to say, between a cathode and an anode, or two electrodes of opposite polarity. The cathode is of a conducting material such as copper, and yes there’s an anode at the other end – I’m talking about the early forms, because in modern times it starts to get very complicated. Faraday in the 1830s noted a light arc could be created between the two electrodes, and later Heinrich Geissler, who invented a better vacuum, was able to get the whole tube to glow – an early form of ‘neon light’. They used an induction coil, an early form of transformer, to create high voltages. They’re still used in ignition systems today, as part of the infernal combustion engine

Jacinta: So do you want to explain what a transformer is in more detail? I’ve certainly heard of them. They ‘create high voltages’ you say. Qu’est-ce que ça veux dire?

Canto: Do you want me to explain an induction coil, a transformer, or both?

Jacinta: Well, since we’re talking about the 19th century, explain an induction coil.

Canto: Search for it on google images. It consists of a magnetic iron core, round which are wound two coils of insulated copper, a primary and secondary winding. The primary is of coarse wire, wound round a few times. The secondary is of much finer wire, wound many many more times. Now as I’ve said, it’s basically a transformer, and I don’t know what a transformer is, but I’m hoping to find out soon. Its purpose is to ‘produce high-voltage pulses from a low-voltage direct current (DC) supply’, according to Wikipedia.

Jacinta: All of this’ll come clear in the end, right?

Canto: I’m hoping so. When a current – presumably from that low-volage DC supply – is passed through the primary, a magnetic field is created.

Jacinta: Ahh, electromagnetism…

Canto: And since the secondary shares the core, the magnetic field is also shared. Here’s how Wikipedia describes it, and I think we’ll need to do further reading or video-watching to get it clear in our heads:

The primary behaves as an inductor, storing energy in the associated magnetic field. When the primary current is suddenly interrupted, the magnetic field rapidly collapses. This causes a high voltage pulse to be developed across the secondary terminals through electromagnetic induction. Because of the large number of turns in the secondary coil, the secondary voltage pulse is typically many thousands of volts. This voltage is often sufficient to cause an electric spark, to jump across an air gap (G) separating the secondary’s output terminals. For this reason, induction coils were called spark coils.

Jacinta: Okay, so much for an induction coil, to which we shall no doubt return, as well as to inductors and electromagnetic radiation. Let’s go back to the cathode ray tube and the discovery of the electron.

Canto: No, I need to continue this, as I’m hoping it’ll help us when we come to explaining transformers. Maybe. A key component of the induction coil was/is the interruptor. To have the coil functioning continuously, you have to repeatedly connect and disconnect the DC current. So a magnetically activated device called an interruptor or a break is mounted beside the iron core. It has an armature mechanism which is attracted by the increasing magnetic field created by the DC current. It moves towards the core, disconnecting the current, the magnetic field collapses, creating a spark, and the armature springs back to its original position. The current is reconnected and the process is repeated, cycling through many times per second.

A Crookes tube showing green fluorescence. The shadow of the metal cross on the glass showed that electrons travelled in straight lines

Jacinta: Right so now I’ll take us back to the cathode ray tube, starting with the Crookes tube, developed around 1870. When we’re talking about cathode rays, they’re just electron beams. But they certainly didn’t know that in the 1870s. The Crookes tube, simply a partially evacuated glass tube with cathode and anode at either end, was what Rontgen used to discover X-rays.

Canto: What are X-rays?

Jacinta: Electromagnetic radiation within a specific range of wavelengths. So the Crookes tube was an instrument for exploring the properties of these cathode rays. They applied a high DC voltage to the tube, via an induction coil, which ionised the small amount of air left in the tube – that’s to say it accelerated the motions of the small number of ions and free electrons, creating greater ionisation.

x-rays and the electromagnetic spectrum, taken from an article on the Chandra X-ray observatory

Canto: A rapid multiplication effect called a Townsend discharge.

Jacinta: An effect which can be analysed mathematically. The first ionisation event produces an ion pair, accelerating the positive ion towards the cathode and the freed electron toward the anode. Given a sufficiently strong electric field, the electron will have enough energy to free another electron in the next collision. The  two freed electrons will in turn free electrons, and so on, with the collisions and freed electrons growing exponentially, though the growth has a limit, called the Raether limit. But all of that was worked out much later. In the days of Crookes tubes, atoms were the smallest particles known, though they really only hypothesised, particularly through the work of the chemist John Dalton in the early nineteenth century. And of course they were thought to be indivisible, as the name implies.

Canto: We had no way of ‘seeing’ atoms in those days, and cathode rays themselves were invisible. What experimenters saw was a fluorescence, because many of the highly energised electrons, though aiming for the anode, would fly past, strike the back of the glass tube, where they excited orbital electrons to glow at higher energies. Experimenters were able to enhance this fluorescence through, for example, painting the inside walls of the tube with zinc sulphide.

Jacinta: So the point is, though electrical experiments had been carried out since the days of Benjamin Franklin in the mid-eighteenth century, and before, nobody knew how an electric current was transmitted. Without going into much detail, some thought they were carried by particles (like radiant atoms), others thought they were waves. J J Thomson, an outstanding theoretical and mathematical physicist, who had already done significant work on the particulate nature of matter, turned his attention to cathode rays and found that their velocity indicated a much lighter ‘element’ than the lightest element known, hydrogen. He also found that their velocity was uniform with respect to the current applied to them, regardless of the (atomic) nature of the gas being ionised. His experiments suggested that these ‘corpuscles’, as they were initially called, were 1000 times lighter than  hydrogen atoms. His work was clearly very important in the development of atomic theory – which in large measure he initiated – and he developed his own ‘plum pudding’ theory of atomic structure.

Canto: So that was all very interesting – next time we’ll have a look at electricity from another angle, shall we?

 

Written by stewart henderson

October 1, 2017 at 8:14 pm

What’s Weatherill’s plan for South Australia, and why do we have the highest power prices in the world? Oh, and I should mention Elon Musk here – might get me more hits

with 2 comments

just a superhero pic to rope people in

I’ve written a few pieces on our electricity system here in SA, but I don’t really feel any wiser about it. Still, I’ll keep having a go.

We’ve become briefly famous because billionaire geek hero Elon Musk has promised to build a ginormous battery here. After we had our major blackout last September (for which we were again briefly famous), Musk tweeted or otherwise communicated that his Tesla company might be able to solve SA’s power problems. This brought on a few local geek-gasms, but we quickly forgot (or I did), not realising that our good government was working quietly behind the scenes to get Musk to commit to something real. In March this year, Musk was asked to submit a tender for the 100MW capacity battery, which is expected to be operational by the summer. He has recently won the tender, and has committed to constructing the battery in 100 days, at a cost of $50 million. If he’s unsuccessful within the time limit, we’ll get it for free.

There are many many South Australians who are very skeptical of this project, and the federal government is saying that the comparatively small capacity of the battery system will have minimal impact on the state’s ‘self-imposed’ problems. And yet – I’d be the first to say that I’m quite illiterate about this stuff, but if SA Premier Jay Weatherill’s claim is true that ‘battery storage is the future of our national energy market’, and if Musk’s company can build this facility quickly, then it’s surely possible that many batteries could be built like the one envisaged by Musk, each one bigger and cheaper than the last. Or have I just entered cloud cuckoo land? Isn’t that how technology tends to work?

In any case, the battery storage facility is designed to bring greater stability to the state’s power network, not to replace the system, so the comparisons made by Federal Energy Minister Josh Frydenberg are misleading, probably deliberately so. Frydenberg well knows, for example, that SA’s government has been working on other solutions too, effectively seeking to becoming independent of the eastern states in respect of its power system. In March, at the same time as he presented plans for Australia’s largest battery, Weatherill announced that a taxpayer-funded 250MW gas-fired power plant would be built. More recently, AGL, the State’s largest power producer and retailer, has announced  plans to build a 210MW gas-fired generator on Torrens Island, upgrading its already-existing system. AGL’s plan is to use reciprocating engines, which executive general manager Doug Jackson has identified as best suited to the SA market because of their ‘flexible efficient and cost-effective synchronous generation capability’. I heartily agree. It’s noteworthy that the AGL plan was co-presented by its managing director Andy Vesey and the SA Premier. They were at pains to point out that the government plans and the AGL plan were not in competition. So it does seem that the state government has made significant strides in ensuring our energy security, in spite of much carping from the Feds as well as local critics – check out some of the very nasty naysaying in the comments section of local journalist Nick Harmsen’s articles on the subject (much of it about the use of lithium ion batteries, which I might blog about later).

It’s also interesting that Harmsen himself, in an article written four months ago, cast serious doubt on the Tesla project going ahead, because, as far as he knew, tenders were already closed on the battery storage or ‘dispatchable renewables’ plan, and there were already a number of viable options on the table. So either the Tesla offer, when it came (and maybe it got in under the deadline unbeknown to Harmsen), was way more impressive than others, or the Tesla-Musk brand has bedazzled Weatherill and his cronies. It’s probably a combo of the two. Whatever, this news is something of a blow to local rivals. What is fascinating, though is how much energetic rivalry, or competition, there actually is in the storage and dispatchables field, in spite of the general negativity of the Federal government. It seems our centrist PM Malcolm Turnbull is at odds with his own government about this.

So enough about the Tesla-Neoen deal, and associated issues, which are mounting too fast for me to keep up with right now. I want to focus on pricing for the rest of this piece, because I have no understanding of why SA is now paying the world’s highest domestic electricity prices, as the media keeps telling us.

According to this Sydney Morning Herald article from nearly two years ago, which of course I can’t vouch for, Australia’s electricity bills are made up of three components: wholesale and retail prices, based on supply and demand (39% of cost); the cost of poles and wires (53%); and the cost of environmental policies (8%). The trio can be simplified as market, network and environmental costs. Market and network costs vary from state to state. The biggest cost, the poles and wires, is borne by all Australian consumers (at least all on the grid), as a result of a massive $45 billion upgrade between 2009 and 2014, due to expectations of a continuing rise in demand. Instead there’s been a fall, partly due to domestic solar but in large measure because of much tighter and more environmental building standards nationwide as part of the building boom. The SMH article concludes, a little unexpectedly, that the continuing rise in prices can only be due to retail price hikes, at least in the eastern states, because supply is steady and network costs, though high, are also steady.

A more recent article (December 2016) argues that a rising wholesale price, due to the closure of coal-fired power stations in SA and Victoria and higher gas prices, is largely responsible. Retail prices are higher now than when the carbon tax was in place in 2013.

This even recenter article from late March announces an inquiry by the Australian Competition and Consumer Commission (ACCC) into retail pricing of electricity, which unfortunately won’t be completed till June 30 2018, given its comprehensive nature. It also contains this telling titbit:

A report from the Grattan Institute released earlier in March found a decade of competition in the market had failed to deliver better deals for customers, with profit margins on electricity bills much higher than for many other industries.

However, another article published in March, and focusing on SA’s power prices in particular (it’s written by former SA essential services commissioner Richard Blandy), takes an opposing view:

Retailing costs are unlikely to be a source of rapidly rising electricity prices because they represent a small proportion of final prices to consumers and there is a high level of competition in this part of the electricity supply chain. Energy Watch shows that there are seven electricity retailers selling electricity to small businesses, and 12 electricity retailers selling electricity to households. Therefore, price rises at the retail level are likely to be cost-based.

Blandy’s article, which looks at transmission and distribution pricing, load shedding and the very complex issue of wholesale pricing and the National Energy Market (NEM), needs at least another blog post to do justice to. I’m thinking that I’ll have to read and write a lot more to make sense of it all.

Finally, the most recentest article of only a couple of weeks ago quotes Bruce Mountain, director of Carbon and Energy Markets, as saying that it’s not about renewables (SA isn’t much above the other states re pricing), it’s about weak government control over retailers (could there be collusion?). Meanwhile, politicians obfuscate, argue and try to score points about a costly energy system that’s failing Australian consumers.

I’ll be concentrating a lot on this multifaceted topic – energy sources, storage, batteries, pricing, markets, investment and the like, in the near future. It exercises me and I want to educate myself further about it. Next, I’ll make an effort to find out more about, and analyse, the South Australian government’s six-point plan for our energy future.

References and more reading for masochists

http://www.abc.net.au/news/2017-03-10/tesla-boss-elon-musk-pledges-to-fix-sas-electricity-woes/8344084

http://www.adelaidenow.com.au/business/sa-government-announces-who-will-build-100mw-giant-battery-as-part-of-its-energy-security-plan/news-story/9f83072547f41f4f5556477942168dd9

http://www.smh.com.au/business/sunday-explainer-why-is-electricity-so-expensive-20150925-gjvdrj.html

http://www.skynews.com.au/business/business/market/2017/03/27/accc-to-find-out-why-power-prices-are-so-high.html

http://www.adelaidenow.com.au/news/south-australia/south-australia-will-have-highest-power-prices-in-the-world-after-july-1-increases/news-story/876f9f6cefce23c62395085c6fe0fd9f

http://indaily.com.au/news/business/analysis/2017/03/07/why-sas-power-prices-are-so-high-and-the-huge-risks-of-potential-fixes/

http://www.theaustralian.com.au/opinion/columnists/graham-richardson/jay-weatherill-must-come-clean-on-elon-musks-battery-deal/news-story/f471b33ebdf140a71b41e0b0bea7894f

http://www.news.com.au/technology/environment/climate-change/why-higher-electricity-prices-are-inevitable/news-story/042712e35c08bf798ed993d13ee573ea

Written by stewart henderson

July 14, 2017 at 10:55 am

on the preliminary report into the future of the NEM – part 2

leave a comment »

session-3-impact-on-us-ancillary-services-markets-from-variable-renewable-energy-3-638

Chapter 5 of the report focuses on the challenges to NEM system reliability caused by increasing VRE penetration, and on possible reforms to the system to accommodate these changes. Price signals, bidding, and market cap prices and floors, as well as many other terms dealt with in this chapter, are definitely outside my sphere of knowledge or interest, but I feel duty bound to try and make sense of them. For a useful beginner’s guide to the NEM, check out this ABC site, though it dates from 2010, and it’s fascinating to note how things have changed since then. The AEMO was only established in 2009.

The NEM is an ‘energy-only’ market, rather than a capacity market. An energy-only market is one in which the companies generating energy are paid for the electricity they sell. In a capacity market they would be paid for keeping generation capacity available to cover what might be a fluctuating demand. With an energy-only market, producers would presumably be focused on demand, not wishing to provide more of something they can’t sell when demand is down, as it has been in recent times. However, base load demand, which is intermittent and unpredictable, becomes a particular problem when investment in the kind of generators that provide base load power is low. The report has this to say on the matter:

The NEM relies on price signals (subject to market price caps and floors), performance standards and market information to incentivise the development and retirement of generation infrastructure. When there is sufficient baseload supply, average prices tend to be low, signalling that no new investment in base load generation is needed. When base load supply tightens, average prices increase, signalling that investment in base load generation is needed. Peaking generators respond to similar patterns but look to higher price periods associated with peak demand.

I don’t really understand this, especially the bit about peaking generators, which sounds as if there are separate generators for peak demand, but that can’t be right. In any case, what this chapter tells me is that the economics of electricity generation in a transforming and uncertain market are fiendishly difficult to comprehend and control. The review ends the chapter, and all other chapters, with consultation questions which help concentrate the mind on the issues at stake. These include questions about the NEM’s reliability settings, liquidity in the market for forward contracts to ensure supply for business and commercial enterprises (and the effect of increasing levels of VRE on forward contracts, and how this can be catered for), and other questions about creating or ensuring future investment.

Chapter 6 deals with the problem of the seemingly ever-increasing cost of electricity to the consumer. The chapter divides itself into sections on wholesale costs and retail pricing. It seems Australia no longer experiences low electricity costs by OECD standards. Network investments have recently driven prices up, and further rises are expected due to generator closures, the international price of gas, and constraints on gas supply. Again the report emphasises the role of gas, at least in the interim:

Gas has the potential to smooth the transition to a lower emissions electricity sector. Gas generation provides the synchronous operation that is key to maintaining technical operability with increased renewable generation until new technologies are available and cost-effective. Furthermore, gas is dispatchable when required.

It seems there’s an intergovernmental understanding that reform is desperately needed to develop and incentivise the local gas market. There are many roadblocks to successful reform, which are currently affecting wholesale costs which will lead to higher retail prices.

Some 43% of current residential electricity prices are made up of network charges, mostly for distribution. Many network renovations were necessary to meet revised standards. A 2013 Productivity Commission inquiry criticised ‘inefficiencies in the industry and flaws in the regulatory environment’ in respect of the planning of large transmission investments and management of demand. Consumer concern about rising prices is driving reform in this area, but we’re yet to see any clear results. Also, there is a difficult balance to be struck between system reliability and cost. A significant proportion of consumers have expressed a willingness to live with reduced reliability for reduced cost.

There has been a difficulty also in forecasting demand, and therefore the spread of cost. Reduced peak demand in the period 2008 to 2013 wasn’t foreseen. The reduction, likely driven increasing electricity costs, was a result of many factors, such as solar installations, energy efficiencies and reduced consumption. There’s a plan to introduce ‘cost reflective pricing’, which means ‘charging prices that accurately reflect the cost of providing network services to different consumer groups’. This is expected to reduce peak demand overall, as will increasing use of solar and, in the future, battery storage.

Retail pricing is another matter, and according to the report there is a lack of transparency in the retail market. Retailing electricity is obviously complex and involves covering wholesale costs as well as billing, connections, customer service, managing bad debts, marketing, return on investment, inter alia. We can only determine whether the retail market is operating fairly when these costs are open to scrutiny.

Chapter 7 deals with energy market governance from a national, whole-of-system perspective. The report stresses urgency on this, though given the complexity of the system and the divided views of policy-makers, it’s unlikely that decisions on integrating the system and making it more flexible will be forthcoming in the immediate future. The governance of the NEM is divided between policy-maker (the COAG Energy Council), rule-maker (AEMC), operator (AEMO) and regulator (AER, the Australian Energy Regulator). None of these bodies, the report notes, are integrated with bodies advising on emissions reduction. Again, the report doesn’t advance a plan for an improved governance system, but posts consultation questions for how improvements might be made. These include amendments to various rules and guidelines, methods for improving accountability and transparency, and expedited decision-making in a rapidly transforming market.

The report includes a number of appendices, the first and most important being a comparison of the NEM with other energy systems and markets worldwide, including those with a large market share of VRE, such as Denmark and Ireland. It is noted that the transformation of these markets, as well as larger markets in Spain and Germany, is being managed apparently without compromising energy security. However, the variety and complexity of many overseas markets and systems makes comparisons well-nigh impossible for someone as uninitiated as myself. Suffice to say that the role of interconnectors for system security is very important in many European regions, and support from governments for a more flexible system to accommodate VRE is more widespread.

Written by stewart henderson

January 2, 2017 at 9:09 am

South Australia and electricity revisited

leave a comment »

1476136506464

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.

Written by stewart henderson

December 25, 2016 at 4:04 pm

on the preliminary report into the future of the NEM – part 1

leave a comment »

1481670998372

Australia’s Chief Scientist, Alan Finkel, who also happens to be a regular columnist for Cosmos, Australia’s premier science magazine, of which I’m a regular reader, has released his panel’s preliminary report on our national electricity market (NEM), and it has naturally received criticism from within the ranks of Australia’s conservative government, which is under pressure from its most conservative elements, led by Tony Abbott amongst others, who are implacably opposed to renewable energy.

The report confirms that the NEM is experiencing declining demand due to a range of factors, such as the development of new technologies, improved energy efficiency and a decline in industrial energy consumption. It makes a fairly reasonable assumption, but one unwelcome to many conservatives, that our electricity market is experiencing an unprecedented and irreversible phase of transition, and that this transition should be managed appropriately.

The NEM has been in operation for over 20 years, and the recent blackout here in South Australia (late September 2016) was its first real crisis. The issue as identified in the report is that variable renewable energy (VRE) sources are entering and complicating the market, which heretofore has been based on the synchronous generation of AC electricity at a standard system frequency. VRE generation is multiform and intermittent, and as such doesn’t sit well with the traditional system.

There are a number of other complicating issues. Improvements in building design and greater public awareness regarding emissions reduction have led to a decrease in overall energy consumption, while high peak demand on occasion remains a problem. Also the cost of electricity for the consumer has risen sharply in recent years, largely due to network investment (poles and wires). It’s expected that prices will continue to climb due to the closure of coal-fired power stations and the rising cost of gas. Interestingly, the report promotes gas as a vital energy source for this transitional period. It expresses concern about our overseas sales of gas, our low exploration rates, and negative attitudes to the fuel from certain states and territories. Rooftop solar systems, numbering more than 1.5 million, have further complicated the market, as the Australian Energy Market Operator (AEMO) understandably finds it difficult to measure their impact. System integration, which takes solar and wind energy system contributions into account, is clearly key to a successful NEM into the future.

The report also stresses Australia’s commitment to emissions reductions of 26-28% by 2030. It points out that business investors are turning away from fossil fuels, or what they call ’emission intensive power stations’, and financial institutions are also reluctant to back such investments. Given these clear signals, the report argues that a nationally integrated approach to a system which encourages and plans for a market for renewables is essential. This is clearly not what a backward-looking conservative government wants to hear.

So the report describes an ‘energy trilemma’: provision of high level energy security and reliability; affordable energy services for all; reduced emissions. More succinctly – security, affordability and the environment.

In its first chapter, the report looks at new technology. The costs of zero-emission wind turbines and solar PVs are falling, and this will maintain their appeal at least in the short term. Other such technologies, e.g. ‘concentrated solar thermal, geothermal, ocean, wave and tidal, and low emission electricity generation technologies such as biomass combustion and coal or gas-fired generation with carbon capture and storage’ (p13), are mentioned as likely technologies of the future, but the report largely focuses on wind and solar PV in terms of VRE generation. The effect of this technology, especially in the case of rooftop solar, is that consumers are engaging with the market in new ways. The penetration of rooftop solar in Australia is already the highest in the world, though most of our PV systems have low capacity. Battery storage systems, a developing technology which is seeing cost decreases, will surely be an attractive proposition for future solar PV purchasers. Electric vehicles haven’t really taken off yet in Australia, but they are making an impact in Europe, and the AEMO has projected that 10% of cars will be electric by 2030, presenting another challenge to an electricity system based largely on the fossil fuels such vehicles are designed to do without.

The management of these new and variable technologies and generators may involve the evolution of micro-grids as local resources become aggregated. Distributed, two-way energy systems are the likely way of the future, and an Electricity Network Transformation Roadmap has been developed by CSIRO and the Energy Networks Association to help anticipate and manage these changes.

In chapter 2 the report focuses on consumers, who are becoming increasingly active in the electricity market, which was formerly very much a one way system – you take your electricity from the national grid, you pay your quarterly bill. With distributed systems on the rise, consumers are becoming traders and investors in new forms of generation. The most obvious change is with rooftop PV. The national investment in these systems has amounted to several million dollars, with the expectation that individual households will be generating electricity more cleanly, more efficiently, and also more cheaply, notwithstanding the traditional electricity grid. Developments in battery storage and other technologies will inevitably lead to consumers moving off-grid, likely creating financial stress for those who remain. The possibilities for developing micro-grids to reduce costs will further complicate this evolving situation. Digital (smart) metering and new energy management software empower consumers to control usage. And while this is currently occurring mostly at the individual level, industrial consumers will also be keen to curb usage, creating added pressure for a more flexible and diverse two-way market. The report emphasises that the focus should shift more towards demand management in terms of grid security. One of the obvious problems from the point of view of consumers is that those on low incomes, or renters, who have little capacity to move off-grid (or desire in the case of passive users), may bear the burden of grid maintenance costs at increasing rates.

Chapter 3 deals with emissions. In reference to the Paris Agreement of 2015, which has been ratified by Australia, the report makes this comment which has been picked up by the media:

While the electricity sector must play an important role in reducing emissions, current policy settings do not provide a clear pathway to the level of reduction required to meet Australia’s Paris commitments.

The current Renewable Energy Target does not go beyond 2020 and national policy vis-à-vis emissions extends only to 2030, causing uncertainty for investors in an already volatile market. Clearly the report is being critical of government here as it has already argued for the primary role of government in developing policy settings to provide clarity for investment. The report also makes suggestions about shifting from coal to gas to reduce emissions at least in the short term. The report discussed three emissions reduction strategies assessed by AEMO and AEMC (Australian Energy Market Commission): an emissions intensity scheme, an extended large-scale renewable energy target, and the regulated closure of fossil-fuelled power stations. The first strategy is basically a carbon credits scheme, which was assessed as being the least costly and impactful, while an extended RET would provide greater policy stability for non-synchronous generation, so adding pressure to the existing grid system. Closure of coal-fired power stations would reduce low-cost supply in the short to medium term. Base load supply would be problematic in that scenario, so management of closures would be the key issue.

Chapter 4 looks at how VRE might be integrated into the system. It gets a bit technical here, but the issues are clear enough – VRE will be an increasing part of the energy mix, considerably so if Australia’s Large-scale renewable energy target is to be met, along with our international commitment vis-a-vis the Paris Agreement. However, VRE cannot provide spinning inertia or frequency control, according to the report. Basically this means that they cannot provide base load power, at a time when coal-fired power stations are closing down (nine have closed since 2012) and eastern states gas is being largely exported. The Hazelwood brown coal power station, Australia’s largest, and one of the most carbon intensive power stations in the world, will cease operation by April next year.

The difficulty with non-synchronous, distributed, intermittent and variable energy generation (e.g. wind and solar PV) is that these terms seem to be euphemisms for ‘not effing reliable’ in terms of base load, a problem currently being encountered in South Australia and likely to spread to other regions. The report identifies frequency control as a high priority challenge.

Frequency is a measure of the instantaneous balance of power supply and demand. To avoid damage to or failure of the power system the frequency may only deviate within a narrow range below or above 50 Hertz, as prescribed in the frequency operating standards for the NEM.

It’s likely that this narrow range of frequency proved a problem for South Australia when it suffered a blackout in September. I’ll look at what the report has to say about that blackout next time.

national electricity consumption - apparently on the rise again?

national electricity consumption – apparently on the rise again?

Written by stewart henderson

December 22, 2016 at 7:15 pm