By Phil Kreveld
If you’ve ever had the pleasure of eating a mille-feuille—a classic French pastry—you’ll no doubt appreciate the delicate layering of crisp, buttery puff pastry alternating with layers of crème pâtissière.
But what does a French dessert have to do with the electricity grid? Well, we are doing a great job making a mille-feuille of the national electricity system. Layer on layer, we are adding operational scheme upon scheme interleaving them with complication on complication.
But unlike the wonderful French pastry, our creation is anything but heavenly. The problem in the kitchen is that the basics including the ingredients are the wrong ones. Many of the kitchen hands should be sent out as their ‘expertise’ turns out be nothing but dogged persistence with recipes they learnt a century ago!
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Wind the kitchen clock back to 1994. It was then that the advice of Fred Hilmer on increasing competition in all spheres of the Australian economy was also applied to electrical energy supply for the nation. Anybody could horn in on existing state-owned generators. The punters could buy their electricity from whomever in the market place. The networks were of course the fly in the ointment, being monopolies. They would be subject to oversight—and they could not engage in selling energy because that would give them an unfair advantage.
We are living the competitive dream today. So much so that many punters have decided that nothing is cheaper than making your own electricity, never mind the plethora of call centres who are ready to trade. For those folk without solar on the roof, the Commonwealth Government is strong-arming the traders, to not charge for electricity as the sun sails past the zenith. None of this could be foreseen in 1994. But rather than chucking out the Hilmer recipe book, we are clinging to it.
Today we have generators who pay to stay connected, we have home grown electricity to match the large generators. Projections to 2050 indicate that we’ll have 15 times today’s capacity for twice today’s energy consumption. This leads to ‘cheap as chips’ electrical energy. But who’ll pay for the over-capacity? That will be the punters as energy charges head south and network charges head north.
No one back in 1994 could foresee the advent of solar or that the odd induction wind generator then, would grow into forests of pylons and nacelles, festooning hill and mountain range crests. The induction generator of then, having to run at super-synchronous speed, and thus minimum wind speed-dependent, has been replaced by DFIG and full-inverter technology. Solar cell physics continues to challenge the Shockley-Queisser efficiency limits. SiC MOSFETs provide more rugged switches for inverters. Electrochemistry advances yield better energy density storage.
Despite these rich ingredients for re-engineering the nation’s electricity system, we cling to traditional concepts for voltage and frequency stability appropriate for 1994 when the forerunner for the Australian Energy Market Operator (AEMO) was founded. The Australian Energy Regulator—the umpire for fair play among networks and generators—and the Australian Energy Market Commission came along in 2005. Together they administer the National Electricity Law—including the Power of Choice.
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Rather than a nutritious and simpler cake, we have opted for the baking of multi-layer ‘delicacy’ for the nation’s electricity system. Rather than taking the straightforward engineering and economic solution, recognising the dynamic two-way energy flow system that has evolved, we are choosing to impose schemes such as VPP and FFCAS. The former creates ‘generators’ among the individual punters, acceptable to the regulators. The latter provides some form of frequency response to help AEMO manage the grid. Ignored, because the recipe book says they can’t are the distribution networks themselves—the natural aggregators.
Rewriting the rulebook—1994 is a long time ago—doesn’t seem to occur to anyone. ‘Ring-fencing’ prevents the obvious solution to recognising dynamic distribution networks, letting them store excess energy generated by millions of household and business solar for use after dark and for pumping into transmission. For want of recognising the obvious, we are making a mille-feuille, heaping on more sugared layers (for which read, skimming off the punters with VPP schemes).
Finally, there is the incentive to build more and more transmission, mostly for sporadic power flow but to supply grid strength—more layers, all profitable to the builders but ensuring that tariffs aren’t going to drop any time soon. The mille-feuille will turn out indigestible.
