Australian Energy Market Commission Review 2018: an edited synopsis of the AEMO Chief’s explanatory article of the review

Australian Energy Market Commission Review 2018: an edited synopsis of the AEMO Chief’s explanatory article of the review:
On 20 March 2018 the AEMO Commission reliability panel of experts and consumer advocates released its review. The following is a partial set of quotations taken from an article published in theAustralian Newspaper of 20 March 2018 on page 28. The article is written by Anne Pearson, Chief Executive of AEMO.
“The report will surprise many. There is in fact enough generation capacity, or MW, in the power system over the short and medium turn. Australia is not running out of electricity right now. But we still have a problem. The national grid has become more unstable with more weather driven generation in the mix. The technical characteristics of power production have changed and we have to manage the power system differently….
“In 2016-2017 the power system dropped outside secure technical limits on 11 occasions, including South Australia’s system-wide black out. ….Eleven incidents within 12 months is historically high, up from seven the year before, four in 2014-15, and two and one in the years prior. ….
“The past decade has delivered big volumes of of capacity from weather-driven generation like wind and solar – all part of helping the nation meet its emissions reduction targets. The challenge is to make it possible for renewables, and any new generation, to be incorporated into the power system safely.
“In 2016-2017 the power system dropped outside secure technical limits on 11 occasions, including South Australia’s system-wide black out. ….Eleven incidents within 12 months is historically high, up from seven the year before, four in 2014-15, and two and one in the years prior. ….
“The past decade has delivered big volumes of of capacity from weather-driven generation like wind and solar – all part of helping the nation meet its emissions reduction targets. The challenge is to make it possible for renewables, and any new generation, to be incorporated into the power system safely.
“Power system frequency is less stable for technical reasons. The technical reasons are eye-glazing but in overall terms the changing generation mix is making the system harder to control. There is less time for the operator, AEMO, to recover the grid from sudden equipment failures before frequency collapses and blackout happens.” (interruption to edited transcript in order to explain the frequency of AC power as used in the Australian grid.)

Transcriber’s note: Australia uses 240 volt AC domestic electricity. (Higher AC voltages are also transmitted over high tension lines in order to reduce transmission line losses). In AC – alternating current – electricity the charge in the line reverses from negative to positive (and so on, in an alternating fashion) 50 times a second. In the domestic one, there are two peaks – a positive 240 volt and a 240 volt negative peak – which occur 50 times a second. It takes time for the peak voltages to build up from 0 volts to 240 (positive or negative ) each 50 th of a second. And if one were to graph the shape of the graph over time between the two peaks it would look like this:  
( image of a sine wave where V- max and V+ max (in our example) = 240 volts (for the sake of example, it probably is a big higher to start with due to voltage drop over distance) . The voltage in the Australian electricity grid changes polarity 50 times a second – that is, it has a frequency of 50 Hertz (50Hz). The problem of many generators producing AC (alternating current) is this: Old fashioned generators (ie those using steam to turn turbines to produce ac power) connected to the same national grid can synchronise each other to the same 50 hz frequency. The big old turbine generators have lots of moving mass and lots of electrical torque behind them. And when two or more of these are connected together on the same grid – even though they are far apart, their movement and phase is brought into line (into the same “phase”) with all the others. Here’s an experiment which helps illustrate the principle. a. Obtain two or more little 3 volt electric motors and force fit a little wheel to each motor. Now wire them together, terminal to terminal like for like. If you have a friend, get them to hold one motor while you hold the other. now turn the wheel attached to your motor. Without your friend doing anything (always a positive thing to get your friend to do) the motor he or she is holding will turn in exact sychronisation with the movement of your motor. Move your wheel back and forward . Your friends motor will do the same, exactly the same. Now make the wires connecting the two motors much longer. You in the kitchen and your friend in the toilet. Even though you cant see your friend (this may be a good thing or a bad thing) the motors will do the same thing together if one wheel of one motor is moved. They stay in synch. If you have two mobil phones you can prove it by filming the two motors. This is base-load synchronisation or at least a rough but good enough illustration of it. (ignoring the fact we are using dc motors in this thought or actual experiment, but that’s the only difference). If electric motors as an illustration are too complicated, imagine this. Imagine the power grid as if it were a huge balloon. The volume of the balloon when full of air is the amperage. The rate at which air is pumped into the balloon is the voltage. In an ac system such as Australia’s it is important that that each generator blows in at the same time. If the generators were people trying to inflate the balloon, it would be counter productive to have half the people blowing into the balloon when half the people were sucking air out of the balloon. All illustrations have their limits. Each generator has to have exactly phase relationship to all other generators at each moment of each second. Big turbines are good at this, it comes naturally. They have large factors of mechanical and electrical inertia. Just like the two little motors, they mirror each other’s voltage phase. when one is at + 240 volt, so are all the others, when one is at zero volts (which happens 50 times a second) so are all the others. when one is at – 240 volts, so are all the others. The base-load is in voltage phase lock step. This simple mechanical and electrical lock step explains why the traditional grid has lasted so long, whether the old fuel used was coal, nuclear, gas or oil. The advantage electrically is the automatic lock step of voltage phase big generators with large diameters and inertia (both physical and electrical) bring to the grid.
On the other hand renewables generally, with the exception of hydro turbine generators, cannot lock themselves into the voltage phase of the ac national grid. They can’t do it naturally, they need electronic add on gizmos to do it for them. Let’s apply this to how solar panels try to mimic the voltage phase or frequency of the grid:
Solar panels produce direct current which must be converted into ac of the correct voltage and voltage phase by the solar system’s invertors and associated system components. The phase synchronisation of solar generation is done by electronics. Electronics are designed with mathematics based on theory. The electronics of each system (and there are millions of separate solar generator arrays in Australia) try to mirror the gird and try to produce the voltage phase resident in the grid. There is no intrinsic electrical or mechanical inertia automatically forcing the same synch in voltage phase. Nothing is perfect and phase inaccuracy results across the huge Australian grid. Usually it works fine though. Generally phase error remains within the tolerance of the system. As old big generators age and are removed from the grid, and as renewables are added to make up the loss of capacity grid phase and at times, grid available power become strained. Stability becomes an increasing an increasing concern. What is needed is a master sychronizer which can force the diverse generator equipment – from wind, solar and conventional turbine into more perfect sych. What is needed is more energy storage which can be released when demand exceeds supply for short periods. In an extreme example of phase instability, if half the generators are at V- max (see the graph attached here) at the exact same time as the other half of the myriad generators feeding the grid are at V+ max ? None of course, and the myriad generators will be straining themselves. Perhaps some would see a short circuit and blow up. I’m not sure about that. So some engineers find a mixed generator renewable powered grid to be more than inconvenient. They see it as unstable and just waiting for expensive events to happen. End of illustration of grid synch stability in a 50 Hz ac grid. (Maybe add a torch globe to your two 3 volt motors experiment. Wire in the globe between the two motors. power each motor in rotational synch and watch the globe light up. turn one motor clockwise and the other one counter clockwise and watch the globe not light up. Keep doing that until your motors both get hot. Back to the quotes.

The CEO of AEMO goes onto to say in this matter grid stability : “BUT THIS PROBLEM CAN BE SOLVED. THERE IS ROOM FOR OPTIMISM AND THINGS ARE ALREADY IMPROVING. THE COMMISSION IS PRIORITISING NEW RULES TO HELP AEMO CHANGE THE WAY IT MANAGES THE POWER SYSTEM. To date we have already made several rules to help the immediate situation, and there are more to come. Fixing system security is not a headline grabber. It involves many, small technical measures. Each on their own may not sound dramatic but they are vital to securing for consumers. ….

“WE ALSO RELEASE A SECOND REPORT TODAY FOR OUR FREQUENCY CONTROL REVIEW. IT NOTES TRIALS OF NEW KINDS OF WIND FARM TECHNOLOGY THAT CAN HELP MAINTAIN GRID SECURITY – A GREAT EXAMPLE OF HOW TECHNOLOGY IS RESPONDING TO THE ECONOMIC AND SECURITY NEEDS OF THE POWER SYSTEM…. WE HAVE A ONCE IN A GENERATION OPPORTUNITY RIGHT NOW TO SECURE THE FUTURE OF RENEWABLES AND NEW TECHNOLOGIES IN THIS NEW LOOK GRID. …

“Meanwhile, we continue to work on the other most pressing issue in the market today, finding the lowest cost ways to restore system security by addressing the technical complexities brought on by changing energy technology.” end selected quotes.

Please consider contacting AEMO for a full copy of the reports. Nowhere in her brief public briefing of the reports does the CEO state or imply that the planet is doomed unless Australia goes nuclear or unless South Australians accept their fate as the guardians of the world’s high level nuclear waste, to be imported and dumped, as some hope, upon Eyre Peninsular. Given that it has been clear for some years that the world is in the cusp of a radically changing energy generation technology – a cusp similar to that seen at the start of the oil and petroleum revolution or indeed the original electricity revolution – only the short sighted would adhere to the habit of clinging to old ways and now quite old technologies. Such as nuclear power. Where energy can be converted from one form to another with ever greater economy and efficiency, the need to invoke Einstein’s famous formula (the basis of the energy release by neutrons during fission (200 million electron volts per atom fissioned) (bulk of which is wasted in a reactor) is not required. Due to new ways of converting energy from one form (light) to another (electricity) directly, power transformation is merely at the start of its technological lifespan. Those old methods which rely on fuel and which, for power generation, have to consume fuel and thus produce waste have, to some extent or another reached the zenith of their usefulness and approach the upper limits of their market penetration. They will all be around for a long time. It is time the energy market accepted that it is now a diverse space, with many types of technologies being utilised.

While nuclear power at it’s most frenzied sees itself as the planet’s saviour, the oldies among us can remember a time when the industry said the same thing. Nuclear will save us from climate change just like it saved us from Communism? I do not thing so. No technology is a saviour, all technology is just a tool to aid humanity meet its needs. Sales skills often involve the invoking of hysteria and that is something which was clearly threat to the survival of the planet from the 50s to the 80s and that threat is not over yet.
(transcription of selected quotes will be continued shortly. I have a headache right now. Though I hope to finish before the Rapture. If I dont, you know why its incomplete. (which is ok ’cause only the pro nuclear will be left confused.)
“The end of the world is nigh without us. You need Nuke to be saved.” Westinghouse Toshiba press release.

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