rss
21

Can Tasmania be turned into Australia’s peak load generator?

Print Friendly

rsz_99d5ac5ae7253bcb7a0c9a4c8591b1ce

On April 20, our PM Mr Turnbull, locked in a political hiatus on almost every front, announced that Canberra is to fund a feasibility study into a project that would essentially switch Tasmania’s hydro system from a base load system to a peak load system that feeds the nation.

It is important to emphasise, at this point, that this is about feasibility and comes at the behest of the Tasmania Premier searching for an infrastructure investment windfall.

Mechanics aside, the net result of their basic proposal would be that instead of Tasmania generating its own power requirements – while using Basslink to trade any surplus or shortfall (as we presently do) – the hydro system would be ramped up massively so that the Tasmanian system would export maximum power during peak times then virtually shut down the system and import power massively during off-peak periods.

There are so many implications to this that I will simply summarise a few of them here in dot points:

• Perhaps an easy way for ordinary citizens to visualize this fundamental operational change is to compare it to how Davey and Macquarie Streets in Hobart have been turned into virtual raceways, to handle ever growing peak traffic – to the extent that the state government has been recently leaning over Hobart council to hot them up even further by removing parking along those thoroughfares and restricting pedestrian crossovers.

• We need to keep in mind that Tasmania does not generate all of its own energy needs and is presently a net importer. A hotted up Tasmanian power system would not generate any more hydro renewable energy than it does, it would simply be turned into a buffer, importing power so as to release it later on at peak times. It’s a way of storing coal-fired power but labeling it as clean hydro power.

• The sales pitch being used – framing Tasmania as a ‘renewable energy engine’ for the nation – feeds a popular Tasmanian sentiment, but is somewhat dishonest. Extra power generated by the system would be simply converting imported coal-fired power into water storage then feeding it back to the Mainland at other times. That represents, at the very least, a twenty percent loss of energy just in transmission.

•  The single existing Basslink interconnector is grossly insufficient to handle these projected loads, meaning that the entire enterprise hinges absolutely on the funding of a second and possibly third Basslink interconnector at about $1billion apiece.  This cost, together with the cost of altering Tasmanian Hydro infrastructure, should not be viewed lightly. Cost would most likely be the killer.

• Renewable energy advocacy groups have been lobbying for a long time for the development of electricity storage to help cope with the intermittency of solar and wind power, so this scheme could theoretically be welcomed by some of those groups. However, it is important to understand that in the absence of truly massive investment in renewable energy generation there is no way the Snowy and Tasmanian hydro electric systems can absorb the amounts of power being purported unless that power is coal generated. The intent behind these schemes, for at least the medium future, is to enable more burning of coal.

• Though ‘pumped hydro’ has become in vogue of late, the Tasmanian hydro system already has significant capacity to generate peak power over sustained load and its water storages can cope with virtually any amount of short-term imported power without needing to augment this storage capacity with pumped storage dams. The main limitation to hotting the Tasmanian system up further is the number of generating sets at each power station and this would, no doubt, be under consideration.

• What are the implications for Tasmania? This is mostly guesswork right now. Not even Hydro Tasmania would have proposed configurations nutted out … though it has previously indicated that pumped hydro is not practical or sensible in the Tasmanian situation. However, we can safely identify two principle impacts, no matter how this mooted project would be specifically implemented.

1.  Further loss of autonomy: By fully integrating into the national grid, Tasmanian energy consumers would become undifferentiated from those in Melbourne of Sydney. The state would lose much of its branding as a clean-green state supplying itself with hydro power. For the Tasmanian people this would also represent a further loss of pride and identity.

2.  Radical changes to river system flows: Running the power stations at maximum output then backing them off means radical changes to downstream river flows. And this means, in turn, radical change to freshwater ecologies. The only way to ameliorate this would be to construct a series of buffer dams in wilderness rivers, below existing dams. I’m trying to imagine how ecologists and wilderness advocates would take to all this.

• The Tasmania public needs to be better informed on these implications before this notional scheme gets out of hand. Meanwhile, the proposal is so far fetched economically it’s not a good idea to start seeing it as a fait accompli. The Prime Minister has announced a feasibility study that’s all, just as he has announced the same with regard to augmenting the Snowy Scheme. Mr Turnbull dearly wants to be regarded as the infrastructure prime minister and to hang his coat on that nail.

• Ever since Tasmania ran out of rivers to dam and Hydro Tasmania wound down its dam making operations, environmental groups such as the Wilderness Society have turned their attention away from energy issues, not seeing dam building as a continuing threat to nature protection. I think we may see their interest suddenly re-ignited.

• The most important thing for the community to do, in the meantime, is to not accept the rhetoric that little Tasmania – producing less than five percent of the nation’s electricity, and not even being self sufficient – is going to be suddenly transformed to become a ‘powerhouse’ for the nation.

It’s probably smart political rhetoric on the part of Will Hodgman, but his main problem is that it is simply fanciful. The feasibility study is likely to show the rhetoric up as nothing more than wishful thinking – though we can probably expect a half-baked, face-saving outcome.

*Chris Harries is an environmental educator specialising in energy supply & demand issues. He is a member of the Climate Tasmania advisory body and drafted the original Tasmanian Environmental Law Handbook. He has been writing on social advocacy issues since the mid 1970s.

Source: Tasmanian Times. Reproduced with permission.  

RenewEconomy Free Daily Newsletter

Share this:

  • George Darroch

    Let’s address a few of these points:

    “It’s a way of storing coal-fired power but labeling it as clean hydro power. • The sales pitch being used – framing Tasmania as a ‘renewable energy engine’ for the nation – feeds a popular Tasmanian sentiment, but is somewhat dishonest. Extra power generated by the system would be simply converting imported coal-fired power into water storage then feeding it back to the Mainland at other times.”

    In short time this would be capturing excess renewable intermittents, not coal.
    If you run this as a ‘stored hydro’ bank these losses are halved.

    “The single existing Basslink interconnector is grossly insufficient to handle these projected loads, meaning that the entire enterprise hinges absolutely on the funding of a second and possibly third Basslink interconnector at about $1billion apiece. This cost, together with the cost of altering Tasmanian Hydro infrastructure, should not be viewed lightly. Cost would most likely be the killer.”

    Yes, but the cost of not building it could be greater, if it means more expensive storage on the mainland.

    “In the absence of truly massive investment in renewable energy generation there is no way the Snowy and Tasmanian hydro electric systems can absorb the amounts of power being purported unless that power is coal generated.”

    That’s what we’re talking about here. Massive amounts of renewable is planned for the next five years alone.

    • Steve

      Yes I tend to agree. Australia will need to invest very large amounts of money over the next two decades to replace pretty much all of our current coal power stations. In third world countries our power stations would already be considered obsolete!
      The question is what to replace it with? Regardless of how it is replace, the ability to store energy are going to be the ones highest up the value chain in future.

  • Chris Fraser

    Ok so the new and pumped hydro is limited. How does the interconnector shape up with new wind development ?

    • Chris Harries

      In the ten years since Basslink came on board the net energy flow through it has been southward. The facility is way short of being fully utilised for northerly flow. It has a very handy 600 MW capacity for peak northerly flow. However, because it can, doesn’t mean it does. We have a competitive electricity market and Mainland producers can undercut on price.

      Wind generators mesh in with hydro almost as a perfect marriage, the hydro storage being able to easily buffer the intermittency factor of almost any amount of new wind installations that are on the horizon here.

      Near term wind developments in Tas are not sizeable enough to warrant investment in a second inter-connector.

      In the very long term Tasmania has potentially some 2000 MW of wind potential – if turbines were installed on every feasible site. This is looking so far into the future the state would have to look at its own growing power demand by then, and also what is happening on the Mainland in this regard won’t be staying still.

      • Chris Fraser

        And they could include King Island in the connector’s route. We could have dairy, lots of 18-hole golf, and wind. This sounds like a lovely spot to visit.

  • George Darroch

    “Further loss of autonomy: By fully integrating into the national grid, Tasmanian energy consumers would become undifferentiated from those in Melbourne of Sydney. The state would lose much of its branding as a clean-green state supplying itself with hydro power. For the Tasmanian people this would also represent a further loss of pride and identity.”

    You’re already part of the NEM, this just increases the integration – to support an increase in renewables. You’ll still be the hydro state, and this will allow you to export more of your intermittent wind.

    “Radical changes to river system flows: Running the power stations at maximum output then backing them off means radical changes to downstream river flows. And this means, in turn, radical change to freshwater ecologies. The only way to ameliorate this would be to construct a series of buffer dams in wilderness rivers, below existing dams. I’m trying to imagine how ecologists and wilderness advocates would take to all this.”

    Obviously, any proposals have to be sensitive to both reservoir and river levels and flows and minimise local environmental impacts. No buffer dams are necessary – that’s a furphy.

  • MikeH

    Given the history of Tas Hydro, I can understand the hostility to their grand (empire building) plans for pumped hydro and the wariness about the environmental impacts. There is no point damaging Tasmania’s environment when we have not yet started to exploit renewable resources like off shore wind which is also rapidly falling in cost.

    While additional storage can be useful, it is always far more efficient to use it than store it. Hence the interest in Tasmania’s relatively undeveloped wind resources the in north-west which are less correlated with the mainland, particularly SA, wind.

    According to Giles’ earlier report, John Tamblyn found that Tasmania could likely support 730MW of additional wind capacity even without a second inter-connector. That could also help Tasmania become self sufficient without the need for additional pumped hydro.

    What we really need is fewer brain “farts” from Turnbull and a more integrated nation wide plan for a 2030-2050 fossil fuel free grid which is capable of being adapted as new technologies come online and fall in cost.

  • Tom

    The big announcement was about “pumped hydro” in Tasmania.

    The big question I’ve got is: WHERE???

    All of our existing dams except Lake Gordon, Great Lake, Arthurs Lake, and Lake Echo are spilling (or likely to soon spill) in winter-spring, so for these existing dams pumped hydro would only be feasible from late spring to late autumn. Good for PV, not so good for wind.

    I read an article about it on the ABC website a couple of days ago where they were talking about something like a network of 16 pumped hydro schemes in Tasmania, doubling our power producing capacity (although of course not our energy producing capacity, although the article neglected this).

    This article referred to a “second interconnector feasibility study”, which I read, and which only had one reference to possible pumped hydro – up to 220MW plonked right on Lake St Clair. There’s nothing existing in that region that could be used, and if they’re thinking about raising Lake Sappho or Lake Riengeena in the Walls of Jerusalem National Park to use as their uphill storage, then GOOD LUCK!

    Secondly, Hydro Tas can’t even get their arbitrage so wrong at the moment – imagine how hopeless they’d be if they had pumped hydro to deal with too. Yesterday we were buying power for $130/MWh, today we are selling power for $110/MWh. In November we were importing 100MW for $15/MWh – we should have been importing 500MW at that price, and surprise surprise, we are now low on water and buying plenty of power most days at more than $100/MWh which, if we’d bought more in Spring, we could be selling for that price. I reckon I could have made the state at least $50 million, possibly $100 million extra if I was in charge of the arbitrage – what a waste!

  • PeterT

    Pumped storage does not require massive reservoirs, just enough to store power for a day, unlike “baseload” hydro systems that need to store water for maybe a year. If the mainland needs pumped storage, build small dams local to the big loads and save both the capital cost of the massive transmission system (Basslink) and the inevitable inefficiencies of transmission losses. This proposal seems purely political.

    • Ian

      The day to day variation in renewables output, more specifically, Solar’s ,let’s say – unique – generation profile needs some storage, not much, just enough to tide over until the next production day. New pumped hydro is unfortunately competing directly with battery storage in this application. New pumped hydro is not getting cheaper whereas the opposition – battery technology- is. So, for this application pumped storage hydro gets a ?X- why not just build battery storage at the site of the intermittent generators?

      The other type of hydro, which basically converts a free resource – rain- into electricity is a primary generator technology. It’s competitors would be other generators, namely wind, solar, and the smoke-stack types of power generation. It is generally competitive in LCOE, and has a unique ability to provide both ‘baseload’ continuous generation and is very dispatchable, this makes it more desirable than both wind and solar, and competitive with those greenhouse-gas machines, the emissions of which shall not be named. There are some serious limitations to once-through hydro, these are namely, 1. Destruction of mountainous and riperian habitat. 2. Limitation of the actual rainfall resource. Combining hydro with wind and solar just makes so much sense. The water storage capacity of the dams can be conserved, whilst wind and solar are available and hydro can be dispatched when these are not. The fortunate thing is that these technologies are so compatible, combining them is Gestalt.

      • PeterT

        I fully understand the synergy of solar and hydro – I’m off-grid with a hybrid solar/microhydro system of my own. And the same should work on a larger scale WITHIN Tasmania. What I don’t understand is the proposal to use Tas to provide pumped storage for the mainland, with the huge capital cost and inefficiencies involved. I still think it’s a political stunt.

  • Ian

    What a shame to dismiss Tasmania’s role as a energy storage resource so out of hand. Environmental concerns must obviously be paramount and pumped hydro may not be particularly financially viable. The question is how well can the river systems that have already been dammed tolerate diurnal variations in water flow? The existing generation capacity is about 2200MW and this could conceivably be upgraded to another 20 or 25%. Tasmania’s wind resource and it’s off shore wind resource is worth developing. It’s own demand varies from 1000 to 1800MW, unless wind farms are willing to spill air when domestic demand is low, the demand potential is limited by this 1000MW minimum and the current Basslink of 550MW+-. This means that Tasmania can only ever install 1550MW of wind, good for the view, but not good for the economy, they may have to resort to cutting down trees to feed their people! A second Basslink of similar size to the existing one could allow at least 2000MW of wind to be economically installed. At a capacity factor of 40% 2GW of wind could produce 7000GWH of electrical energy a year.

    The water resource is only good for 9000GWH a year or running its generators continuously at 1000MW. Tasmania’s demand is about 11000GWH a year and could go up to 13000GWH in the next few years, this difference must be imported or generated locally. Importing 2000 to 5000MWH could well be from smoke-stack power stations!

    Tasmania will only ever be small-fry to the Victorian Electricity Market and an improved Basslink will allow Tasmania’s shortcomings in demand/load to not stifle its wind farm development.

    Chris Harries is right, Tasmania will only ever be an energy back-water, an island sometimes forgotten off the Australian map if they don’t change their mentality and sustainably develop their wind resources, and to do that they need a better Basslink.

    • Chris Harries

      Hi Ian, at the end of the day Hydro Tasmania still has to bid into the national electricity market using rules of the NEM. If it fails to bid competitively then it doesn’t get the sales. Over-the-top investment in transmission infrastructure would not be helpful. The $92 million per annum contracted rental of existing Basslink is a significant financial burden on the state’s utility. Adding to that financial burden shouldn’t be thought of flippantly. It is, indeed, the reason why the business case for a second interconnector looks very forlorn and why the Tamlyn Report of two weeks ago urged caution.

      Yes, the existing Tasmanian dam network along with augmented wind capacity (some of which is on the drawing board) can enable Tasmania to play a very useful role in helping to stabilise the national grid. This is the presently case utilsing the existing Basslink interconnector. That’s what it was designed for.

      I’m urging caution in overblowing the case that Tasmania can switch from being a net power importer – and one that is subject drought-driven power shortages – to a position where it is being politically touted as saviour of the nation’s power problems. At the end of the day it comes down to what is efficient investment and what are the alternatives. We should be open on all fronts and not be too romantic about possibilities.

      Unfortunately climate change has negatively affected the output of the Tasmanian hydro-electric system (as has happened with a number of hydro systems around the world) and this has rendered Tasmania short of self sufficiency. The rupture of Basslink 1 happened at a time when Tasmania was IMPORTING (my emphasis) some 40 percent of its electricity load and a number of commentators believe that overload is likely to have caused that breach, though there is no confirmation of that.

      The two private wind farms the are currently mooted would go some way towards Tasmania being able to restore a position of 100 percent self-sufficiency (i.e. in an average rainfall year). We should take hard headed steps in these directions. I think Tasmania needs to have at least surfeit of 20 percent self sufficiency before the sums for a second interconnector can stack up.

      Meanwhile, many environmental colleagues down here believe that if we can become net positive in electricity production then Tasmania should be looking at electrification of transport here as a primary policy objective.

  • Kevin O’Dea

    It is only one year ago that a severe drought was drying up the Hydro lakes in Tassy to the point where power rationing was being imposed upon industries in this state. This combined with a break in the Bass Strait cable which cut our grid off from the Mainland grid for more than six months whilst desperate efforts were made to locate and repair the cable breakage. The Liberals at both state and federal levels are simply making political mischief with this phantom idea of Tasmanian hydro power being used as a renewable energy source for mainland grids. They have learned nothing whatsoever from the experience of climate change in this part of the world.

  • Trent Deverell

    Ultimately Tasmania’s “Green” capacity is limited by the capacity of BassLink.

    Tasmania currently has enough nameplate capacity to over-load BassLink if the Hydro and Wind was fully re-purposed to mainland peaking support.

    But we shouldn’t loss sight of what happened a few years ago when Tasmania’s hydro was over-extended and then a period of dry weather occurred.

    Indeed Tasmania should ensure it is absolutely bullet-proof with enough alternate RE capacity via pumped hydro, wind and solar + battery to ensure a repeat never happens. 1st priority!!!

    But to consider spending $1bn to add each nominal GW of extension lead capacity to supply the mainland from Tasmania and as more RE gets added very rarely if ever in reverse … is that actually viable.

    Given a few years and the benefit of hindsight the Australian mainland would likely be best served with more RE solution, of their own.

    Now that the cost curve is making non-fossil solutions cheaper and cheaper, Tasmania would be best served looking after its on independent energy security and just let the mainland sort out its own energy transition.

    • Ian

      Is a Billion dollars a lot for a 1GW of transmission capacity? That’s $1000/KW. If its run to capacity for 1/2 the time for 20 years the cost per KWH is 1c/KWH. Refine these sums if you like, but even 5c/KWH is probably a viable cost for energy transmission.

      • Trent Deverell

        I can tell you right now a 2nd BassLink cable will be lucky to be utilised for 5% of the time, and in any case assuming 5c that will likely become 12c once commercial lending, ROI demands and further OPEX costs are factored and passed thru to the end-user market.

        But it doesn’t end there as Tasmania also has to spend additional money on further generation capacity, so it can have enough extra electricity to fill that cable capacityl!!

        … and then they’ll likely need more on-shore transmission re-investment as well as upgrades at the mainland end to facilitate the extra flow.

        For $1Bn/GW of genuine generation capacity, any number of mainland RE options would almost certainly be more attractive to the energy market investors if indeed the mainland turns up short on power.

        A bunch of solar and wind farms (+storage) placed in the vicinity of closed Hazelwood would re-use the existing transmission infrastructure and aspects of the local skills base, and along with the announced snowy pumped hydro, one might suggest loss of legacy capacity is likely to be re-addressed fair more cheaply than a 2nd BassLink.. It is just a cable to pass energy, it doesn’t add anything to overall capacity.

        That said South Australia is looking like coming good with the announced solutions, but for time being things are a tad tight no thanks to GenCo’s that have an issue with turning on their gas capacity. .

        The big boggie is probably NSW as it has been relying on Victoria’s brown coal excess for far too long. On a dozen or so hot summer days each year if Victoria and Qld can’t then tip in enough, well the NSW parliament will have a ugly backlash to sort out..

        Ultimately more RE + storage is where we need to go, but short-term inertia of existing vested interests and conflicted politics certainly makes things ugly.

  • Just_Chris

    I have to admit I disagree with this article at pretty much every level. If we are to transition to 100% zero carbon getting the maximum out of all of the available hydro is a very good thing. Expanding / adding to the link so we never spill a drop of hydro power is a good thing. Better connection between Tasmania and the mainland is a bonus for wind as it provides a much wider geographic area for wind farms – a lot of which could be built in Tasmania, which has a similar area and wind resource to Scotland who currently have 5 GW of wind installed. From other comments I’ve read, without an increase in bass link capacity Tasmanian wind would be limited to around 700MW. Adding extra turbines to existing hydro so we can draw down faster at times of high demand or during particularly wet times is a good thing. Being able to recycle some of the water via pumped hydro is a good thing, especially if water levels are low. Adding to the hydro facilities in Tasmania may reduce flooding, another good thing. Having a massive dispatchable resource deeper in the NEM will reduce the overall cost of power.

    I think a new coal power plant in Australia is unlikely but I do think that a doubling of solar in the next 5 years is possible, potentially even a tripling. If that happens and if there are large dispatchable plants in the system like hydro and gas turbines then I can see nothing but more coal being pushed out of the system.

    The cost of any upgrades would need to be factored in as would the environmental impact but I could see a turbocharged tassie being an excellent source of low cost green power.

    • stucrmnx120fshwf

      Trying again, I can see the sense of it, Australian renewables targets are highly subsidized, by rooftop solar forward capital, our desert solar farm totals are pathetic. Given that 25% of our deserts, at 75% of the mainland, can supply a trillion tons of liquid hydrogen per year, that’s underutilized power, hence to some extent the MHI (Mitsubishi Heavy Industries LTD.) Trials of liquid hydrogen shipments, culminating in the bulk shipments in 2020, why not create stability here in Tasmania. The damns would always be 75% full, frequent flows could be organized, with the best environmental outcomes, 97% of all global power storage, is pumped hydro. We need lots of electrical power, electric vehicles, cheap as internal combustion engine vehicles, with a fraction of the maintenance and power costs, of IC vehicles.

      Industries will sometimes want to run 24 hours a day, resources will be smelted in Australia, because of our cheap energy, okay the cable might cost $A a billion, but if solar is dramatically cheaper than coal, soon, why not. The power corridor​s are already in place, less costly, than Snowy Mountains 2.0, but we must compete with sea water damns, alongside the mainland coast, which are near enough to the national power grid.

  • Chris Harries

    What hasn’t been mentioned yet in these discussions is what the federal government is able and willing to do. What it has offered here is limited to a feasibility study, nothing more. There are commercial / structural reasons for this.

    Consider that the nation’s electricity network comprises a number of competing pubic and private business utilities. In the wholesale electricity market, each of them is vying for their slice slice of the pie. This is no gentleman’s picnic. Their bottom lines depend totally on being successful in that competitive enterprise.

    Now consider what would happen if the federal government were to overtly fund any one utility to give it a significant market edge over the others. All hell would break loose.

    It’s important to realise this point, because it’s easy to come up with a dreamy scheme, its another to turn that into a commercial proposition that has legs. Tasmania’s worst mistake would be for it to invest very heavily in a manner that produces electricity at an unsaleable price.

    Talk it up or talk it down, whatever one’s instincts on the attractiveness of this scheme, the outcome will boil down to money and financial risk, with a little bit of political opportunism predictably thrown in.

  • Miles Harding

    If anything, Tas could make more use of its very good wind resources and become an average load** supplier to the emergying renewable grid when it’s dark and calm over Victoria.
    It is well paced with large reserves in its hydro dams, providing they are full. I suspect that most of the pumped hydro effect could be achieved by exporting wind energy and deferring consumption of the existing hydo resource when wind is plentiful. In any case, wind (or solar?) will be needed to allow energy beyond that provided by rainfall to be consumed or exported.

    ** I suggest calling it average load because, unlike base load, it is only called on periodically to supply the difference between local supply and use, averaged over 24 hours by batteries or other short term storage or mitigation stragegies.