The future of energy generation and storage

[Value Collector]

This is what I mean by Tesla don’t recommend letting your car sit at 100% charge, there is a sliding bar where you adjust the maximum level your car will charge to (you can do it in the car or on the phone app).

that last 10% they recommend only to charge to if you need it, you can however set your car to finish charging at a certain time eg 6am in the morning, so it hits 100% just before you need to drive to work, or leave on a road trip, so the battery isn’t sitting at the high state of charge for to long.

that’s actually one of the big killers of phone batteries, people let them get to 100% every night and let them sit at that charge all night.

 

[basilio]

Thanks VC. Clearly a quite different application. There does seem to be evidence that rust will produce electricity. I'm just wondering why there doesn't seem to be even a small scale example of this battery for proof of concept.

Ultra-thin layers of rust generate electricity from flowing water

Researchers have shown that iron oxide layers can convert kinetic energy of saltwater into electrical power.

www.sciencedaily.com

Could rust provide an answer to the big energy storage question? - edie

Old bikes and barbecues lying dormant in garages could be covered in stuff that can make large-scale solar energy storage a reality, after researchers found that rust can be transformed into water-splitting solar cell batteries.

www.edie.net

 

[basilio]

Apparently Zinc air batteries are now already available and fit the space of longer term huge storage of power.

Technology – ABOUND Energy

www.zinc8energy.com

 

[Value Collector]

Telsa is getting into the Virtual power plant business using their home batteries (power walls), this leads me to think they could eventually get into Vehicle to grid business in a big way eventually too.

 

[Smurf1976]

Apparently Zinc air batteries are now already available

Primary (non-rechargeable) zinc air cells are what powers most hearing aides as one example of current use. They're also the most practical "drop in" replacement for mercury batteries which are now banned in most (all?) countries due to their toxicity but there's still some equipment around that was built to use them.

On a larger and rechargeable scale, the idea isn't new, has been around since at least the 1960's that I'm aware of and perhaps longer, but in practice other chemistries have had the advantage for the sorts of applications batteries have historically been used for.

An advantage of zinc is that it's relatively cheap and abundant as a material. Australia accounts for about 10% of world production with around a quarter of world reserves. Zinc is known to exist in every Australian state with active mines Qld, NT, NSW, Tas and WA. Small scale mining of it has occurred in the past in SA too.

About a third of Australia's mined zinc is refined to high purity metal at plants in Tasmania and Queensland.

 

[sptrawler]

Primary (non-rechargeable) zinc air cells are what powers most hearing aides as one example of current use. They're also the most practical "drop in" replacement for mercury batteries which are now banned in most (all?) countries due to their toxicity but there's still some equipment around that was built to use them.

On a larger and rechargeable scale, the idea isn't new, has been around since at least the 1960's that I'm aware of and perhaps longer, but in practice other chemistries have had the advantage for the sorts of applications batteries have historically been used for.

An advantage of zinc is that it's relatively cheap and abundant as a material. Australia accounts for about 10% of world production with around a quarter of world reserves. Zinc is known to exist in every Australian state with active mines Qld, NT, NSW, Tas and WA. Small scale mining of it has occurred in the past in SA too.

About a third of Australia's mined zinc is refined to high purity metal at plants in Tasmania and Queensland.

As we keep saying, batteries in reality haven't progressed at the same rate as other technologies i.e semiconductors, metal technology, computer processing power, they really haven't had that huge breakthrough yet.

 

[Smurf1976]

As an update on the situation in Queensland:

Callide unit C3 back in operation as of Monday and has been ramped up gradually to full output so two months after the incident it's back in action.

Unit C3 is physically closest to C4, the one that suffered the major incident, and is technically identical hence the time to check everything and put C3 back into operation.

Units B1 and B2 are further away, indeed strictly speaking they're a separate power station albeit at the same site and with buildings interconnected but they're separate as such and technically different in design. Hence there was no real concern about those and they were returned to service sooner.

As for the damaged (effectively destroyed) unit C4, the official date at this stage is the end of 2022 so still 17 months away. Obviously that's a target date with considerable uncertainty in practice given the scale of work required.

There's been a few near misses with supply in Qld and NSW recently, most recently on 21 July and again on 22 July, where the lights weren't far from going out due to insufficient supply available so having Callide C3 back running will certainly help there and should help subdue some of the upwards pressure on prices seen over the past two months also.

Qld average spot market price for June 2021 was $236.79 versus $42.10 for June 2020.

NSW average spot price for June 2021 was $183.51 versus $51.25 for June 2020.

There'll be some companies who've made or lost significant $ out of all that. Those who are generating or consuming large volumes and who aren't price hedged via suitable contracts.

 

[mullokintyre]

Callide unit C3 back in operation as of Monday and has been ramped up gradually to full output so two months after the incident it's back in action.

Unit C3 is physically closest to C4, the one that suffered the major incident, and is technically identical hence the time to check everything and put C3 back into operation.

Units B1 and B2 are further away, indeed strictly speaking they're a separate power station albeit at the same site and with buildings interconnected but they're separate as such and technically different in design. Hence there was no real concern about those and they were returned to service sooner.

As for the damaged (effectively destroyed) unit C4, the official date at this stage is the end of 2022 so still 17 months away. Obviously that's a target date with considerable uncertainty in practice given the scale of work required.

There's been a few near misses with supply in Qld and NSW recently, most recently on 21 July and again on 22 July, where the lights weren't far from going out due to insufficient supply available so having Callide C3 back running will certainly help there and should help subdue some of the upwards pressure on prices seen over the past two months also.

Qld average spot market price for June 2021 was $236.79 versus $42.10 for June 2020.

NSW average spot price for June 2021 was $183.51 versus $51.25 for June 2020.

There'll be some companies who've made or lost significant $ out of all that. Those who are generating or consuming large volumes and who aren't price hedged via suitable contracts.

Gidday Smurf, you are obviously involved in the industry given your previous comments, so I have a question.
Has there been any indication as to what may have caused the major catastrophe?
Just prior to the event I was reading about two massive solar flares that were predicted to have potentially damaging effects on satellites, communications and power distribution as the electric and magnetic fields around earth are disturbed. I remember being in North America some time in 1989 when a huge solar flare shutdown the power grids in Canada.
Mick

 

[SirRumpole]

Units B1 and B2 are further away,

Nah, they are just bananas.

You were waiting for someone to say that I bet.

 

[Smurf1976]

Has there been any indication as to what may have caused the major catastrophe?

Much speculation and guesswork by many but no firm answers at this stage.

CS Energy, which operates and 50% owns the Callide C station (and 100% owns the Callide B station next to it) has appointed an external engineer, Dr Sean Brady, to lead an independent investigation into the situation.

Of note, Dr Brady has been given an effectively unlimited scope to investigate anything and everything he deems relevant. So that extends not only to the physical plant and equipment but also to any other matter eg company management, policies and procedures, the actions of any individual and so on. The scope of his appointment extends to bringing in any other expert, engineer or otherwise, deemed necessary to assist.

It'll all take a lot of time to work through but my expectation is that there'll be multiple issues ultimately found. It's hard to envisage a single incident causing that level of destruction without there also being some other failure involved either technical or human.

 

[Dona Ferentes]

Crews battle Tesla battery fire at Moorabool, near Geelong


.
https://www.abc.net.au/news/2021-07-30/tesl...elong/100337488

A toxic smoke warning has been issued near Geelong as fire crews tackle a blaze at the site of Australia's largest Tesla battery project.

Fire Rescue Victoria (FRV) said a 13-tonne lithium battery on the Geelong Ballan Road and Atkinsons Road in Moorabool had been fully engulfed by flames.

"Crews are working to contain the fire and stop it spreading to nearby batteries", FRV said in a statement.

No-one was injured and the site has been evacuated.

Fire crews are wearing breathing equipment and the CFA has sent 12 tankers to help tackle the blaze.

The fire broke out during testing of what is expected to become the largest battery in the southern hemisphere as part of a Victorian Government push to transition to renewable energy.

Australian Energy Market Operator (AEMO) said the battery had been isolated and disconnected from the main electricity grid and "there are no implications" for supply. ...........

 

[Sean K]

Crews battle Tesla battery fire at Moorabool, near Geelong

Are these battery blow-ups common?

 

[IFocus]

Are these battery blow-ups common?

Shouldn't happen, protection systems / engineering stuff up by the looks of it, would have thought there would be over temperature , current / voltage protection etc maybe they got the settings wrong Smurf?

Its not that hard.

 

[mullokintyre]

In the early days of Lithium batteries, there were a spate of spontaneous combustion events.
So much so that the FAA banned aircraft from transporting lithium batteries.
They have improved a lot since those early days.
So much so that I now have an FAA approved litium battery in my own aircraft.
If there are enough of them out there, there will be fires.
Just like if there are enough of any vehicle in the world ( Lithium based or not) there will spontaneous fires.
The video from youtube below has gathered all the fires together to suggest there is a major problem with tesla.

But there are a lot of teslas out there to go wrong.
mick

 

[mullokintyre]

Kenya has become another of the countries to successfully generate geothermal generated electricity on a large scale.
from World energy .

Kenya has now more than tripled its production from 198MW to almost 672MW in just six years.
It now generates almost 50% of its electricity from this source.

Australia consumes about 200 terrawats for its 25 million people.
Given that there are 59 million Kenyans, who in total consume about 1700MWh in a year.it highlights how much power we consume in OZ.
Mick

 

[sptrawler]

Are these battery blow-ups common?

The big problem is these massive battery boxes, are actually just jam packed full of individual cells (about the size of a jumbo AA about 65mmX18mm) connected in series/parallel configuration, once a fire starts it will just run rampant through the pack until it runs out of shorts to reignite it.
They have cooling tubes running through and safety cut outs but with a fire, it doesn't follow a certain path, it can jump sectors, so very difficult to stop once it starts, that is why the battery management systems (BMS), have to withstand massive surges as a grid linked battery will have to withstand huge inrush and discharge currents, when system disruptions happen.
This is why we keep saying all this has to be technically driven, not politically or emotionally driven, disasters are a fleeting moment away, when you are talking the energy flows in the grid.
The tests they were doing on the battery, would have been probably been to see how they performed with load rejection or overload, where load is instantly applied and or rejected.
This is just a 85KW/Hr battery:
How many 18650 batteries are there in a Tesla? The most popular Tesla battery pack contains 7,104 18650 cells in 16 444 cell modules. The entailed capacity by the 18650 batteries stands at 85 kWh of energy.

 

[mullokintyre]

The big problem is these massive battery boxes, are actually just jam packed full of individual cells (about the size of a jumbo AA about 60mmX15mm) connected in series/parallel configuration, once a fire starts it will just run rampant through the pack until it runs out of shorts to reignite it.
They have cooling tubes running through and safety cut outs but with a fire, it doesn't follow a certain path, it can jump sectors, so very difficult to stop once it starts, that is why the battery management systems (BMS), have to withstand massive surges as a grid linked battery will have to withstand huge inrush and discharge currents, when system disruptions happen.
This is why we keep saying all this has to be technically driven, not politically or emotionally driven, disasters are a fleeting moment away, when you are talking the energy flows in the grid.
The tests they were doing on the battery, would have been probably been to see how they performed with load rejection or overload, where load is instantly applied and or rejected.

Yo Sptrawler, one thing that people used to comment on was the synchronisation of the network.
From what i remember, the inertia of the big turbines provided a a very stable 50 HZ generation that all other systems were able to sync to.
If all the big continuously running turbines (whether they be gas, diesel, coal etc). are taken out of commission, or only run infrequently, what is the current mechanism for providing a base 50HZ for the non continuous supplies to tie to?
I guess if there are some large Hydro generators to provide the inertia it would be ok, but they sometimes need to be turned off due to lack of water.
Mick

 

[sptrawler]

Yo Sptrawler, one thing that people used to comment on was the synchronisation of the network.
From what i remember, the inertia of the big turbines provided a a very stable 50 HZ generation that all other systems were able to sync to.
If all the big continuously running turbines (whether they be gas, diesel, coal etc). are taken out of commission, or only run infrequently, what is the current mechanism for providing a base 50HZ for the non continuous supplies to tie to?
I guess if there are some large Hydro generators to provide the inertia it would be ok, but they sometimes need to be turned off due to lack of water.
Mick

That is one of the major issues the AEMO is currently trying to deal with, system stability relies on inertia when there is a hit, also all the generating components in the grid have to be able to 'droop' so that they pick up load equivalent to their size and ability. There is no point having the smallest generator trying to pick up all the load in a disturbance and the largest generator picking up nothing.
So all these solar farms and wind generator have to work in a harmonious manner, or everything falls over, that is one problem.
The other problem is as you have mentioned inertia, which at the moment is provided by multiple 100 ton rotors spinning together at 3,000 rpm, as this is retired from service more and more synchronous condensers and pumped hydro etc, will have to be installed throughout the grid, to provide that inertia, add to that the transmission layout has to be configured to the new current flow dynamics and it is a huge job.
@Smurf1976 is the man to talk to about it I'm too old and out of date, these days, the station I worked in is being demolished as we speak.
I'm talking in a very general overview sort of way, @Smurf1976, will give you the nuts and bolts.

 

[SirRumpole]

Yo Sptrawler, one thing that people used to comment on was the synchronisation of the network.
From what i remember, the inertia of the big turbines provided a a very stable 50 HZ generation that all other systems were able to sync to.
If all the big continuously running turbines (whether they be gas, diesel, coal etc). are taken out of commission, or only run infrequently, what is the current mechanism for providing a base 50HZ for the non continuous supplies to tie to?
I guess if there are some large Hydro generators to provide the inertia it would be ok, but they sometimes need to be turned off due to lack of water.
Mick

I'm sure Smurf will be along soon.

As far as wind turbines go I believe they have adjustable blades that keeps them turning at the correct rpm.

Solar cells have inverters that convert dc to ac.

There ended my humble lesson.

 

[Smurf1976]

what is the current mechanism for providing a base 50HZ for the non continuous supplies to tie to?
I guess if there are some large Hydro generators to provide the inertia it would be ok, but they sometimes need to be turned off due to lack of water.

An inverter operating as an islanded power system, that is without the grid, can of itself send out 50Hz with no external reference so long as it's designed to do so.

On a tiny scale the one I've got at home can do that. If the grid goes dead well then the house can be (is) isolated from it via relays and my little inverter will then put itself into operation as a stand alone power system in order to keep the load supplied. So long as the solar panels + battery can supply the required DC current to the inverter, and house load doesn't exceed 5kW, it'll keep running and I'll have 230V 50Hz.

On a larger scale the Dalrymple battery (SA) is at the end of a single transmission line supplying the region and is capable of operation as a stand alone system, that is without the transmission line being in service, if required. So long as the battery has charge in it, which may last quite some time if it's sunny or windy due to the large number of houses with rooftop solar and a wind farm in the area, then the local distribution network will remain live despite being disconnected from the rest of the grid.

On a larger scale though well it's somewhat more complex than that and it's most easily explained by noting what would happen if I drew more than 5kW, even momentarily, from my inverter at home whilst operating in islanded (without the grid) mode. The short answer is a complete loss of supply, it'll shut down. Not so bad if it's just my house but a rather big problem if it's the whole state.

The idea of running a grid without synchronous generation, so that is one based entirely on inverters, is an area where Australia is pushing the limits (globally) at present.

SA does at times generate more wind + solar than local consumption indeed so far as is known to AEMO and others in Australia it has the highest use of wind + solar (combined) of any large power system on the planet. Anywhere using more is a small island etc which doesn't have the same reliability requirements.

Due that situation, the "natural" outcome with respect to the operation of synchronous generating plant (which in SA's case is mostly gas-fired and the rest is using oil-based fuels) is problematic in that often there'd be effectively no such plant in operation, indeed it would literally go to zero. That causes a huge problem in terms of system strength and the ability of the system to withstand faults.

The workaround to the situation has thus far been to simply force the operation of a minimum number of synchronous units, regardless of the economics, so as to maintain system strength. That's expensive and means at times gas is burned whilst wind + solar are throttled back (ie wasted) but it does resolve the technical problem. The numbers have been crunched, there's an official list of acceptable combinations of synchronous plant online, but for the record the most common minimum arrangement in practice is one gas turbine + the steam turbine at Pelican Point power station plus any two (of four) 200 MW steam units at Torrens Island B. Many other combinations exist but that's the most commonly used, largely driven by economics.

A better workaround is the four synchronous condensers being installed, two each at Davenport (near Port Augusta) and Robertstown (about 100km north of Adelaide) substations. They'll significantly reduce, but not eliminate, the need to have synchronous plant online.

The other place of significance is Tasmania.

Between wind farms, rooftop solar and Basslink (since it's a DC link) Tasmania has exceeded 80% non-synchronous generation in the grid. Bearing in mind that unlike SA, Tasmania has no AC interconnection to anywhere else, it's a possible world record. Not confirmed but it plausibly is and even if not then it's certainly right up there pushing the limits in terms of what's been done, anywhere, for a power system of substantial size and complexity.

Making it work in Tasmania comes down to two key things:

1. The Basslink SPS (Special Protection Scheme) which is a bespoke system which gets around the problem that in import (Vic to Tas) mode Basslink represents what would otherwise be an unacceptably large single source of supply relative to the overall system size.

That poses a huge risk if it trips (which has actually occurred on multiple occasions since large inverters aren't particularly stable in operation, they're somewhat prone to random trips). Without the SPS it could very easily collapse the entire system but, thus far at least, the SPS has worked as intended and the lights have stayed on every time.

2. Many of the hydro stations have the ability to run without water as synchronous condensers, meaning there's been no need to build anything specifically for that purpose. Since the need to operate as a syn con occurs when not much synchronous plant is being run for generation, there's no conflict there, the same machine can be used for both purposes.

Water on for generation, water off and in the case of Francis turbines blow the tail water out (with compressed air) for use as a syn con. No need for that step with a Pelton turbine since they're not submerged in normal operation.

Three small open cycle gas turbines in Tas, which are rarely used for generation, are also set up to be run as syn cons. They don't offer the same degree of mechanical inertia as a hydro unit of the same capacity would but they're still sufficient to be useful. Again it's a case of putting the same equipment to multiple uses which saves $.

For the other states there aren't the same issues at a state wide level (though there are in some specific locations - eg at the connection point for wind and solar farms) thus far but Victoria's getting close enough that AEMO has identified and listed suitable combinations of synchronous (coal / gas / hydro) plant that must remain on as a minimum. Same at a regional level for North Queensland where it's a very definite constraint.

Looking ahead, nobody's running any major power system without synchronous plant at all so far as I'm aware. It's being done on a small scale at times, islands and so on, but they generally don't have the same reliability requirements plus their relatively simple power systems could be very quickly restarted if the need arises - just turn the diesel engines on.

It's much harder for a major system where there's cities, heavy industry, electric transport and so on all using it and where a full restart is a very major exercise that could end up taking a full 24 hours or even longer. Can't take so many risks there.

At some point running without any synchronous generation will happen but there's a lot more number crunching and modelling to be done before it happens on a large scale system.

Related to that is not simply how inverters perform but also how they could be made to perform differently. That is, essentially, how they could be made to replicate great big lumps of spinning metal which, whilst far lower tech, does have that inherent robustness and ability to deliver fault currents that anything based around electronics traditionally struggles to match.