By Phil Kreveld
This year’s Australian Clean Energy Summit, held from 16-17 July at the Sydney International Convention Centre, was a thought-provoking exercise highlighting Australia’s progress thus far in the transition to renewables.
There is energy everywhere in the universe. The challenge for humanity is to extract it at a sufficiently fast rate to raise and cool temperatures, to produce artificial light, to raise concrete blocks at building sites, to run production machinery, etc. The fewer transformations energy has to undergo the more we have available to power modern societies. Power is the time-based rate of energy extraction and therefore it’s also the rate of its depletion—something to bear in mind when it comes to the not inexhaustible sources of coal, oil and gas. The second law of thermodynamics basically tells us that ‘there is no such thing as a free lunch’. Energy extraction depletes the opportunity for future extractions (the so-called increase in entropy). Solar energy is also not inexhaustible, but our take-off is miniscule with the almost frictionless rotation of the earth providing hot and cold sinks for its conversion to mechanical power, i.e., wind, and for solar photons to convert to electrons.
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The fewer transformations energy has to undergo, the better off we are. This wasn’t the major theme at the Australian Clean Energy Summit but elements shone through in a number of presentations, for example in the subject of energy storage. Conservation of energy requires giving thought to using it with as few transformations as possible because every transformation, unless it is carried out infinitely slowly, causes energy wastage. The media is filled from time to time with announcements of battery projects and also pumped hydro. Compressed air, on the other hand, is a rarity but such a project was presented at the energy storage stream.
The facility is planned for Broken Hill and will have a 200MW, 8-hour capacity utilising disused mines. The electricity will be ‘stored’ and generated by compressor pump/air driven turbine-generators to power a mini-grid. A point made by the presenters, Hydrostor, was that a synchronous generation capacity is being provided. Pumped hydro, similarly topologically restricted, was also a feature with ex-prime minister Malcolm Turnbull being a notable presence. Converting hydraulic head to electricity or for that matter to heat is a limited-efficiency process, and that also applies to compressed air as the heat generated by the compression process is not necessarily captured but it is in the case of the Hydrostor project. In that regard, one of the interesting presentations by MCA of Tomago described direct use of heat from industrial processes without intermediate conversions to electricity. Imaginative solutions will be required including the use of biogas which can be carbon neutral inasmuch as its formation extracts CO2, later released in the generation cycle.
Christiaan Zuur of the Clean Energy Council stressed the gravity of storage capacity associated with renewable energy generation because of ‘dunkelflaute’, the absence of wind and sun, and wind droughts experienced in the Australian continent. A presentation by Julia Souder of the Long Duration Energy Council and the commentary by Clare Savage of the Australian Energy Regulator once again raised the wasted opportunities of storage and the need for more energy independence in distribution networks. Savage stressed the need for more investment in this sector and that it might well be at a level equalling the need of transmission networks. She said that a change of philosophy regarding distribution networks is needed.
Matthew Warren, previously CEO of the CEC made an interesting comment; ‘rooftop solar lacks parenting’. He opined that rooftop solar was crowding out VRE generation, and his view sheds light on an increasingly acute situation in which distribution’s ‘duck curve’ drops transmitted power to lows, requiring voltage control amelioration measures. Put this in the context of Savage’s rejoinder that ‘rooftop solar needs harnessing’ and a worrying picture emerges in that as Shane Rattenbury, representing the ACT, indicated; consumers are missing out on low energy prices, notwithstanding solar rooftop growth. He saw the solution in smarter smart meters. Furthermore, Rattenbury says that he feels pessimistic because energy policy has become a culture war.
This was echoed by Penny Sharpe, NSW’s energy minister who said that the planning system was not coping with the transition target and that a nuclear generation option with 20-year time window was unrealistic as a solution. Balance this comment with that of Sharpe’s reference to NSW’s statutory review of the state’s 2016 Biodiversity Act, chaired by Ken Henry. In short, biodiversity considerations make demands on the selection of solar and wind farms. Combining biodiversity limitations with social license and you have a recipe for delays in project approvals.
Tasmania’s energy minister Nick Duigan made an interesting observation; ‘building large transmission systems for a relatively small number of customers must have a big cost effect’. The same comment can be made for distribution networks, as Dr Gabrielle Kuiper, DER specialist of IEEFA, pointed out that 53% of distribution wiring caters for 3% of electricity consumers.
Highlights of the summit were an address by Climate Change and Energy minister, Chris Bowen (unfortunately not attended by the writer) and one by Opposition Shadow, Ted O’Brien. He made the case for nuclear generation based on his assessments that emissions have flatlined, prices for electrical energy are up by 39% relative to 2022, and security is impaired through the loss of coal-fired generation. O’Brien’s comments, stripped of any political policy implications, require inspection in that, irrespective of baseload disappearing with the increase in battery storage, technology-wise synchronous capacity is likely to be required in the foreseeable future.
A long-term role for gas is implied, and given the uncertainty in commercialisation of hydrogen, imaginative solutions will be required including the use of biogas which can be carbon neutral inasmuch as its formation extracts CO2, later released in the generated energy cycle. There appeared to be a consensus that gas cannot be eliminated from the renewable transition journey and that a capacity scheme in addition to energy pricing policies will continue to be needed.
A comment on the sidelines of the summit by Matthew Warren, points to the experimental nature of the renewable transition journey. This is privately endorsed by AEMO technologists as a grid without synchronous capacity invites speculation as to its stability and security. A presentation by James Lindley of AEMO highlighted stability aspects including decreasing system strength and the concomitant tripping of distributed solar systems following power system disturbances brought on by decreases in inertia and increasing, sharper power variations.
The role of markets for renewable energy evoked some interesting comments, particularly in regard to services such as VPP and FFCAS. Lachlan Blackhall (ANU) answered his own question ‘what do consumers want’? ‘They want to be left alone, and they want low cost!’ He verbalised what many in the renewable sector feel and/or suspect—“stop the ‘to do lists’ and start some doing”. Surveys taken of conference participants views brought some insights.
A summary of the question ‘what are the most pressing risks to Australia becoming a clean energy superpower?’ and participants comments appears below.
1. Market reform too slow to ‘find’ the missing money (37%)
2. Climate wars/lack of policy stability and certainty (23%)
3. Can’t expand build needed for transmission fast enough (20%)
4. Global capital pulls back from Australia (7%)
5. Insufficient workforce (7%)
6. Contracts market lose too much liquidity (3%)
7. Keeping the system strong and stable.
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The missing money is a refence to the inadequacy of pure energy markets, the point being made by one presenter that the close to zero marginal cost of wind and solar, presents the opportunity for artificial pricing there being no effective energy cost floor, and therefore also, how to price battery-stored energy. A capacity-based pricing mechanism would assist in overcoming this. Minister Sharpe made reference to the Capacity Investment Scheme as a success mentioning that there are currently 19 projects in place with 84 in the pipeline but it is uncertain how many are subject to the Bowen-introduced CIS bidding regime.
Keeping the system strong and stable, interestingly enough, had a near zero rating. Is this because we assume that whatever the technical challenges, they will not slow the transition speed?
