The Electricity Authority (EA) is calling for faster decision-making on firming up the supply of electricity when poor weather conditions limit the availability of electricity.
Their concern is with the so-called NZ Battery Project, of which a pumped hydro scheme in Central Otago is the most prominent option.
This project would supply power when calm weather limits output from wind turbines and arid conditions dry up hydro dams.
At present, coal and gas-fired power plants make up that gap, but the government wants to end this practice.
However, some in the energy sector have said slow decision-making on the battery project is deterring them from their own energy investments.
That is because if the pumped hydro scheme goes ahead, then the large-scale volume of its output could displace demand for their own product.
In a report, the EA appears to support this claim, in a reference to "investment-impeding uncertainty" around the project.
"We invite the Ministry of Business Innovation and Employment (MBIE) to bring forward the completion of the.....NZ Battery Project," the EA says.
"Reduced uncertainty would contribute to more renewable generation investment, and so to lower prices, sooner."
The Otago scheme would work by pumping water uphill in the early hours of the morning when electricity is plentiful and demand is low.
That water would then flow back downhill through turbines to generate electricity in the early evening when demand is high.
The process would then be repeated the next day.
The project is centred on Lake Onslow, about 20 kilometres East of Roxburgh in central Otago. MBIE has made it clear that similar schemes run overseas. But its sheer size and effectiveness could be a problem.
Its potentially chilling effect on rival projects is clear from comments made to the EA, which says; "submissions generally agreed that uncertainty was an issue."
And while those submissions say it is important not to rush the project, in order to get it right, they add "it is crucial to provide clarity how the NZ Battery Project would integrate into the wholesale electricity market ."
At present, New Zealand electricity is 85% renewable on average. The remaining 15% is generated from burning coal or gas. The Government wants to move to 100% renewable, but needs to smooth over the 15% gap first.
The Lake Onslow project is intended to do this, though the Energy and Resources Minister Megan Woods insists there are other options besides Lake Onslow.
MBIE material lists those as hydrogen, biomass such as wood chips, more geothermal electricity or better management of the demand side of the energy equation.
The Lake Onslow project would cost $15.7 billion according to the latest numbers. A feasibility study has been done and the next stage is a full business case.
At this stage, Lake Onslow faces an uncertain future, for political as well as technical and economic reasons.
The National and the Act Party have made clear they oppose the project. The Government wants to continue the process of stage by stage analysis of the merits of the scheme. The Greens are withholding judgement until all the reports are in. Te Pati Maori also wants more information before making a call.
Meanwhile, Megan Woods says any calls to hasten a decision on Lake Onslow are premature.
"No decisions have been made in the New Zealand Battery Project about which option will go forward, so that is a premature discussion."
*Also see this episode of the Of Interest podcast: Could a pumped hydro scheme in Otago free NZ from fossil fueled electricity & help enable a green transition?
105 Comments
It is absolutely right to say that "it is crucial to provide clarity how the NZ Battery Project would integrate into the wholesale electricity market".
If there is no change to the market structure then the project is unviable to its investors (i.e we the taxpayers) because existing generators in the South Island would capture all the value (if any). If change to the market is coming to make the project viable to taxpayers then all other proposals to invest will not be commercial until this critical uncertainty is resolved.
The situation is a mess and needs urgent resolution one way or the other.
So true and we the tax payer got told by deregulation we will have cheaper power (Max Bradford Nat). Hydro is one of the least, easiest maintained infrastructure. Costs to set up but once done very little to keep going yet prints money pity Douglas and Prebble didn't understand that when they flog off our assets yes we were in debt (how are we now and political parties of all colour are saying we should have more debt) but now we don't have the assets. Those think big projects are all still going and earning yet all that dividend is shipped off shore. These power companies are like Enron in how they manipulated the California power grid to drive up prices.
It's NOTHING to do with markets .......... At this price
Interesting cognition skills.
It's NOT about price. It's about long-term societal resilience - and in those terms, even the existing grid is moot.
We really did paint ourselves into a corner when we chose to represent the real with the artificial, didn't we?
Na I think it's about the markets. They'll allocate resources efficiently.
We have potentially limitless energy and resources. Solar, nuclear, wind, hydro - maybe fusion at some point. There's still plenty of coal and oil to burn up. Only the constraints we impose on ourselves are artificial.
Finland just commissioned the largest nuclear power plant in EU even thou the other EU countries complained. Denmark just built and commissioned a new plastic/waste to energy plant even built a ski field on. It Germany and England fired up their mothball coal fired power plants as Russian gas too exspensive. Isn't it strange that the Greens love to talk up the Nordic countries Finland, Denmark, Norway who is in the top ten oil producers) as were NZ needs to be with their welfare and tax systems but yet don't want us using our resources even trying to stop a waste to energy plant in Glenavy.
Waste energy? No such thing. Inefficient retrieval of initial build energy, sure. But that still requires whatever was burnt, to be replaced. Using more energy.
It's flat-out illogical - just like hydrogen from hydro-electricity is illogical. The only way forward is to reduce waste to zero BEFORE it even becomes a waste-stream.
Sigh.
"
The Otago scheme would work by pumping water uphill in the early hours of the morning when electricity is plentiful and demand is low.
That water would then flow back downhill through turbines to generate electricity in the early evening when demand is high. "
is this actually true, do dams magically refill fromlow levels overnight, every night??
Unclear on what you are actually asking here. It's not magic, the water is pumped into the reservoir. The idea is that there are times of the day when we generate more power than we need, so power is "cheap". At those times, we can use some of that power to run the pumps and effectively store that extra power.
It may be cheaper but is there actually a true excess of hydro that can be used that can be used.Recall the original scheme was to smooth out price fluctuations, not hydro supply per se..
Say your dam is half empty at the end of the day, does it overflow at night? You have to propose that there is generally so much water at night that it's actually been spilled at night rather than stored or used directly for hydro.
Electricity usage in the middle of the night is typically half of what it is around peak times, so there is usually water that would otherwise sit in one of the existing reservoirs or be spilled, particularly if there is wind at that time.
Check out the transpower dashboard: https://www.transpower.co.nz/system-operator/live-system-and-market-dat…
And water sitting behind the existing dams acheives way better results than feeding it thru a turbine to generate electricity to pump water up behind a different dam elsewhere after all the losses along the way. Its only when the existing hydro is full and being spilled that it make sense to run a turbine to pump water up a hill elsewhere. And there isn't much of that most years.
When hydro is spilling it will always be generating flat out. If there is a danger that it will spill in the near future then it will be running flat out 24/7.
The operation of the market is too complex to describe in a short post.
Personally I would like it to go back to central planning. That way there would be much more certainty. Way less duplication of effort by disparate generating companies. The only unknown then will be industry. eg Tiwai and others. And does the govt encourage them to come, stay or go.
Personally I think Onslow and its transmission lines is way way too expensive for a generation source that is not net +ve.
Keep a few gas stations as backup. Much cheaper.
The water doesn't get lost in the process. When demand is low you pump water up from reservoir A to higher reservoir B. When demand is high you generate power as it flows through your dam back to reservoir A, where it can still feed through the rest of the system. Even with losses, as prices can easily be 5x as high during periods of high demand vs low demand there is clearly economic sense in it.
You don't understand the merit order stack.
At current conditions, up to about 3500MW, the price is very low <$20MWh, it ramps up quickly to about $150 at 4500MW and is about $1000 at 6000MW. Almost all water not used at low demand/ low prices is stored behind the dam and used for generation when power demand and price goes up. Very little is spilled or wasted unless no capacity at station to generate or there are transmission constraints. Run those hydros more at night and burn more coal during the day to make up missing power and energy.
I can see it now.......
Sorry folks, we are turning off the river at night. We will also turn it off when no one wants our power or if the price has dropped due to too much power from other suppliers. It not your river anymore, it now belongs to a corporate and we determine what flows down it based on what our cash flow is.
You have lost your river to the cashflow stream of the damn owners.
So that's the enviro bit. Nek minute......
Factor in the inevitable Maori ownership claim on the water
.....and this project ain't going anywhere in a hurry!
Dams work by spilling more water when they don't need it via a spillway that goes into a river.
During the night, demand for electricity drops significantly, meaning all the wind/water turbines and thermal stations have to back off their supply of electricity (go here and click on the "NZ Loads" tab). This "spinning down" is a wee bit costly long term, essentially they are lowering their ROI for the assets as they are sitting idle for much of the time. Imagine, if you will, that during period from 12-5am, those powerstations continue to generate their power... something has to use it. That's something is the pumps at Onslow that refill the lake which is something like 600m above the intake, which is a hydro lake itself. During times of peak load (again refer to the graph) or dry years when the hydro stations aren't producing as much, Onslow can generate water and also spill it into the Clutha water scheme to "refill" it for further power generation.
Yes actually three uses in one as Simon Upton put it in supporting it: Of course it does the dry hydro year thing, but importantly it puts a floor under the power price paid to solar and wind generators, but it also puts a cap on the maximum prices in the power system as it would then start generating.
People making comments on here need to do some research and realise that pumped hydro is a very effective scheme that works very effectively overseas. It also can make money by arbitrage - store water when the price is low and generate power with it when it’s high. This happens in a 24 hour timeframe and over months. When water is plentiful you’ll see relatively small amounts used up and down. When there is a major drought it will dip into its deep storage capacity. The economic benefits for anyone using wholesale power - ie business - will be massive.
You would need to build more generation capacity without onslow. Why? Well why does Huntley only run sometimes but the asset sits there in case it’s needed? Because the other sources are unreliable.
You have to build generation capacity for the 0.01% scenario. Which means a lot of wasted capacity.
Rather than building power plants you don’t need 99.99% of the time, it makes sense to build a big lake. When you build the big lake you need less surplus capacity.
Ok. To be able to fill it up your need more. Without it you need more.
Kind of depends how it would be operated. eg If it uses "surplus" eg surplus solar power and generates on a daily basis, that may mean that it isn't full when a dry winter occurs. Or if it uses "surplus" power to fill it up over the long term then that power really was surplus for more normal weather conditions. (Snowfall, rain, wind and sun).
Unreliable is the correct term for their performance They cannot be relied on to meet dispatch (like all other generation has to) even on a two hour ahead schedule, left alone the 48h which the SO wants and is needed to get cold thermals away. .
Remember in August 2021- the power cut event - it happened because they lost 300MW of wind unexpectedly when it was too late to start Huntly. They had to use their reserves so when Tokaau had a problem, there was nothing spare left.
As Australia is finding out, wind and solar are very good at generating when their power isn't needed. There, the lack of predictability has caused massive costs to consumers. Look at domestic power prices in Adelaide.
It sounds good at the hand-waving level of project investigation to say "store water when the price is low and generate power with it when it’s high", but if the very design of your project and its interaction with the market increases the price of power during the storing period and decreases the price when the water is being released, you will not have a commercial project for your investors: -its value will be taken by others in the market.
You need to do the maths on what you said. Take the hint and do it because then you'll not regurgitate such nonsense. (Hint: the storing process would barely make a dent in the energy consumption at low price levels. Further hint: total generation capacity must be built and be available for any peak loads in a 365 day period.)
Lol if roads are worth doing let the private sector build them. If a fire service is worth doing let the private sector do it. If an army is worth having let the private sector do it.
The reason the private sector won’t build it is because:
(A) it reduces the profits by removing hugely inflated prices during shortages
(B) the benefits accrue to consumers and businesses through more stable prices and a private sector provider cannot capture revenue based on those benefits.
This is not true.
Wind generation - currently the cheapest form of generation per kW - can't simply turn on when prices are high. Instead that make make power when the wind blows which obviously varies throughout the day, week, season and year. I.e. When they generate power they generally have to accept whatever price is going.
And a slightly higher price when human-driven-demand is low, but pumping needs from the pumped hydro Onslow scheme are operational, the slightly higher price, actually makes non-continuous generation like wind, solar, tidal, etc. even more viable - and profitable !!!!
This guy clearly hasn't a clue how the NZ electricity system works.
There is next no surplus renewable energy wasted or available at this stage to store in the Hydro battery. Non renewable generation fills in the gaps in periods of renewable shortfall. Otherwise water is taken out of the present storage lakes (batteries) to met demand. As we increase our supply of renewable energy the existing storage lakes will be able to provide significant battery like energy storage. At some point further down the track as we add further renewable energy, particularly volatile wind and solar generation our capacity to smooth demand with the existing lakes and load management will not be sufficient to avoid wastage. I would guess that it is some way down the track before we get to needing this. Given the lead time for these types of projects it is wise to be considering these issues, but it is not an urgent we need it tomorrow situation. If we close the aluminium smelter, then this will increase the urgency.
As others have noted our current fractionated competitive generation system is a nightmare to migrate sensibly. When all the current governing political parties were in opposition they were vehemently opposed to the sale of the power generators (as were many right wing groups), but once in power they did nothing to reverse the situation. If the public vote to give you the power to change things then that what you should do. Use or loose it and otherwise you don't deserve the mandate.The other thing that it calls into question is "who is actually running the country?"
Yeah, we have to be honest, any delivery is at the minimum, 15 years away. But I still think it's a good thing to do and make decisions on pretty fast, the intermittency of renewables is a thing that isn't going away anytime soon.
Only real decisions that would make it a pointless system is for us to go nuclear. Which is a total pipedream given local skills and entry to that market is even further away.
It’s pretty easy to explain how it would integrate. Here I will do it.
The government will pay for the project upfront. Yes it will cost $16B but that is small in the scheme of things.
They will create a new SOE to own and manage the asset when it’s built.
The top 30% of the capacity will be used for short term smoothing of demand - ie the company owning the asset will be charged with using the capacity to smooth prices - pumping water to produce power when prices spike (likely around breakfast and dinner and during, when the wind stops etc - look up the duck curve, happens every day like clockwork). And storing water when prices are artificially low.
This benefits both businesses and generators. Especially productive industries that are absolutely wrecked by unpredictable wholesale power prices.
This activity will produce a profit (sell high/buy low) which will be used to meet the running costs and pay dividends to the government generating a return on the investment.
The bottom 70% of capacity is to be reserved for infrequent dry periods where the scheme will be required to continually pump water to generate power. This will drain the capacity which can be refilled after the dry period is over.
The scheme is not a threat to power producers because it uses more power than it produces. It is about ensuring power is available at the right time - that is a valuable commodity. It actually helps renewable energy producers because without the scheme, renewable energy is prone to getting very low rates because all wind/sun is generating at the same time. This will smooth that effect and can guarantee them a minimum price.
It’s so obvious how this works. There is a big battery in south Australia that prints money doing this. Now this is much bigger and more expensive, but the principle is the same.
the otago scheme sounds like an out-of-date solution,it would have been perfect 50 years ago when the U,K built theirs in Wales,but now that australia is installing 850 MW batteries maybe we can learn from them as they do get on with it and likely will have it in service before we call for tenders.
My understanding is that the economics of this is superior on a $ per kWh basis and it supports multiple use cases. Batteries are good for short term smoothing, especially for grids with a high percentage of renewables to manage instability. New Zealand needs some demand smoothing but not on the same scale - we will always have very high hydro/geo baseload. New Zealand has to cover the dry year risk and only pumped hydro can address that.
Not only that, but onslow is capable of storing that capacity for a period of months or years while losing only a small amount of stored energy to evaporation. Chemical batteries are designed for short term storage.
Furthermore, in a hundred years Onslow would still be there doing the job, with some replacement hardware and maintenance. The battery farm will have been completely replaced perhaps 5-10 times over this period, at a cost not much less than the initial install.
I work in the industry, That gives me access to a whole lot of relevant facts and data that people don't realise the significance of or understand. But all the stuff I quote is public domain. It was an EnergyWatch article that alerted me to the schist leakage and it was confirmed by an engineering geologist working down there. A big problem. And no, mud doesn't seal it, the muddy flow actually indicates it is getting worse.
My "vested" interest is similar to that of academics or consultants, except I actually know how things work.
Yes, I remember your techno-optimism fro a long time back. And we will need people like you, in spades, in the future.
But that future will be very different to the recent past. The problem I have is that we need folk like you (and Bardsley, who I admire for having the foresight) to understand what the future will be like, and THEN tell us whether this, or anything, is appropriate. Currently, you - last I heard, I stand to be corrected) didn't buy into human overshoot, the Limits to Growth, or anything other tha a mutation of BAU. Correct?
And the trouble is that appraisals made through that lens, need to be filtered. Which the Minister has zero chance of doing. I think water-at-height is the most benign battery around and my question is not about that; it's whether we cn maintain the grid at all, post near-term collapse?
Getting the question posed and answered, seems to be near impossible.
Go well
What I do and don't believe in philosophically is irrelevant. I'm insignificant in the scheme of things, having just one three millionth of the voice of NZ and NZ has no influence in the world. Even my daughters' cats don't listen to me.
What I do firmly want to see is NZ having cheap reliable power with minimised impact. To that end, a big wind farm on the top of a ridge (think Titiokura Saddle) is worse in almost every respect than a similar power OCGT.. With regards to operation of a grid, we need reliability and dependability as critical parameters. Certainty of supply of electricity is the lifeblood of modern society. And we are moving ever further away from that.
Water at height has a lot of issues. Vajont killed more people than all the nuke power stations have, including Chernobyl. The latter wasn't even really a power station. It was designed as a plutonium manufacturing site with electricity as a by-product.
'is the lifeblood of modern society'
See what I mean? We need you teccy types to appraise what can be kept, post-collapse (Limits to Growth, ramification probabilities thereof).
But you won't contemplate such a scenario; to you 'modern society' is not negotiable. Bardsley too, I suspect.
https://open.umn.edu/opentextbooks/textbooks/980
Read it Chris - come back with a rebuttal.
Then let's all have the discussion as to what it is that will be being serviced, in the triage years.
The forecast cost was somewhere along the lines of $5K for every man, woman and child in NZ. It would have to do an awful lot of moderating of generation demand (and prices) to give us all payback.
However, the further we have to go towards carbon zero the better the economics will stack up. Coal and gas have to go sooner or later. Biofuels might go someway to fill their gap wrt balancing the grid.
Keep in mind, Onslow generates ZERO extra energy (inefficiencies, leaks, evaporation mean it's a net negative), but makes use of water and energy that would otherwise have just been spilt downstream for zero gain. So we might generate 3MWh to pump water into Onslow, only for that water to generate 2.5MWh when it gets used, but if the water was just going to be ditched anyway, then we're still better off by 2.5MWh
We need to be past that kind of comment, and thinking.
This is not a case of economics, or payback. Sorry about that, but the first world has pumped an artificial proxy-system so much, that it now has no relevance for true accounting (simply put, if you can print unlimited money as debt, who says it is a valid marker within a limited sphere of operations?
Only economists, and those who gather under their pulpits
People are unable to distinguish between power and energy. They are NOT the same
NZ has a significant shortfall of the former over the peaks and an even bigger one of the latter. Typically thermal is 500-1500MW over the daily double peaks (currently its over 1000MW and wind 65MW- Any solar would be zero) and about 7TWh a year. Maybe 10TWh in a dry year..
Having a pumped storage may "solve" your power requirements but will make energy shortfall worse. Generating more from the hydros at night means there is less water during the day for the peaks, increasing the fuel burn.
So you need to add all that overbuild, plus the transmission lines to service them, costs into the cost of Onslow. 10 TWh is about 20 windfarms the size of Waipipi and that was 0.5B - At least 20% more expensive now as the costs have gone up - read the trade papers on manufacturers losses where they are bleeding red ink. That Waipipi cost is about $130/MWh to break even and Onslow is arbitrage so it needs at least $150/Mwh to pay for it. Add in the other charges adds about $150/Mwh for the consumer. How much do you want to pay for power? How many billion are you budgetting for the capital spend??
pumped storage is at best 70% efficient. Nothing comes for free. The inter island bottleneck is a problem. Moving power 1000 km loses 7% of power. Onslow would be great if it was in the Waitakeres. This is a decision that needs to be considered not rushed. Tiwai needs to be paying a real amount for its power at least 20c per kwh . People commenting who know nothing about efficiencies need to do some background research before mouthing off.
Yes - the storage needs to be near the peak requirement - Auckland no doubt. Maybe we should shift Auckland to the South Island. Most of the discussion seems to miss that the need is for extra generation capacity for peak demand with some hard to determine dry and/or sun/wind lows that will stress the system anyway. Doing storage in the South where the major demand is in the North is daft. Hooking Manapouri to the grid might be a better idea for the extra capacity or at least charging Tiwai properly will help develop better resilience - I won't hold my breath on this as EV's need aluminium.
This is an important point. Now is not the future. If we build this and start accounting for electrical transmission costs and efficiency, it may be that we make power close to the dams cheaper. Which would very much influence decisions about where to put high power using industries. Canterbury/Southland may become more than just big farms, instead major industry/technology hubs. This is not to be ignored, the potential future benefits of the project are very unlikley to be included in the analysis as they are too dependent on politics and what if scenarios. But still huge potential.
For instance, AI and video rendering facilities are most likely going to be huge server farms in the future using a lot of power. As they can be anywhere given high speed internet tech/infrastructure, its best for them to be in a location that is fairly cool, to decrease air con costs, has plenty of electricity for cheap and with climate change, has green electricity. Thats a lot of boxes that Southland/Canterbury/lake districts tick.
An interesting point is that NZ currently loses 25% of the generating capacity from moving the electricity from the South Island to the North Island. The generation capacity should be situated in the North Island where it is consumed to get the best overall result for NZ generally. Can this project be done in the North Island, where the transmission lines currently exist, instant savings of 25%.
Let us not forget - Jenny Shipley and then John Key created this bloody power coy mess!
Thankyou National - whats your next disaster idea gonna be?
Sell Transpower complete with the Cook Straight cable perhaps?
I don't like Labour but National has been a disaster over time.
If it goes ahead, as long as NZ designers and contractors are appointed and tax payer funds are not syphoned offshore to some foreign retirement or investment fund.
The government procurement office cannot fall for another international consortium dropping its pants for the tender proposal, only to rape and pillage the contract once engaged.
Onslow does not work on the daily cycle. During a normal years it pumps any symptoms energy available during the floods to the other lake and, when we get a dry hydro year, it releases the water to make up for the loss of power from HYDRO schemes during dry years. This means that it has to have huge storage lakes which is most unusual. Most pumped hydro scheme can generate or pump for between six and 10 hours. Onslow operates on a scale of years.
A key problem in responding to a dry year is knowing that the country is actually in a dry year. There is a risk of letting go a lot of inventory in Feb/Mar/April only to find in May that there is excess wind or rain- so that what looked like a dry year proved to be pretty ordinary.
If there are these misleading cases, where inventory is dropped only to need building up again at cost with no real benefit, the economics of the project could suffer quite badly
I think you are misunderstanding. Onslow is intended to operate on more than one cycle. Yearly, tend to build up reserves when wet and draw down when dry. Daily, pump up when the wind and solar are pumping and release for the evening peak. Perhaps a seasonal cycle as well? The cycles will be superimposed on one another. In a wet year, the daily inflows can be expected to be larger than the daily outflows.
The year-on-year operation will never pay the bills, the daily load balancing arbitrage will generate useful income. The added advantage is the daily load balancing allows us to build significantly more intermittent generation than our grid could currently handle, without risking black outs or backup thermal generation.
Onslow could and should be working on a daily cycle as Simon Upton points out as well as doing the dry hydro year thing. In this way it puts a floor under what wind and solar generators get in times of surplus and a cap on the max. price that generates can charge. However Onlsow may be the wrong choice to do this - perhaps the Tekapo-Puakaki twin would be a better scheme for radically less money but with half the storage (you pump water up to the canal from Pukaki, run it backwards along the canal and pump it up to Tekapo from the other end of the canal - which has been laid so flat it can in fact flow backwards I believe)
Please do a little physics studying, before making such sweeping comments.
Hydrogen is an energy store, not a source. If you're using hydro electricity, you are better using it directly rather than via hydrogen. And you're better storing it in lakes; nothing really contains hydrogen, and that's made worse because it tends to need pressurised for volume/energy reasons.
A good study is of Energy Return on Energy Invested (EROEI). All life, all society needs to be in positive EROEI territory. When something is a loss - battery-charging/discharging, energy-form transition - you need to be very sure the loss is worth whatever you get out of it. We have been used to a massive energy-surplus, but that is reducing fast now.
A lot of people are under the misapprehension that fossil fuel generators are used just for peaking - this is what should be happening but is not in NZs distorted market system. Here gas generators are often kept running through the day and night to keep the price high. Here all generators get the highest price that any generator offers for the next half hour. By keeping some of their hydro back and running their fossils they get windfall profits on their cheap hydros. This is why we need something like Onslow that will buy surplus solar and wind power at a reasonable price and sell power back into the market to block out the fossils at times other hydros are being held back - as well as dong the dry hydro year thing.
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