Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Register Log in
  • Congratulations GregLocock on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

South Australia statewide electricity blackout. 10

Status
Not open for further replies.
The interconnectors are rated at 600 MW (roughly). It was when they bombed out due to overload that the system black cascade really got going. So any intermittency handler has to cope with a 600 MW draw. Mr Musk's Magic Machine gives a 10 minute breathing space. I don't know how long it takes to get a non spinning reserve up to 600 MW. What they should be doing is using the interconnector load as an indicator to bring in non spinning reserves, rather than relying on it running at 100% as it is a cheap source of baseload.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Musk is not the only player in the emerging 'energy storage' market. It's starting to attract some truly big players:

AES and Siemens create joint-venture for energy storage


John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
This is my favorite storage, if you have mountains

They are talking about 2GW x 8hrs, and trains are a well established technology.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
 
Need a lot of train cars to store the equivalent of even a small pumped storage lake. Should be more efficient though.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
 
Round trip efficiency of the 1960s pumped storage in Wales was around 73%. Ain't gonna beat that with a railway.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
I read in one of the referenced items that they're looking for about an 80% efficiency.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
I'd expect train storage to be way more efficient than pumps. A lot faster to reverse too. Interesting! I wonder if they're filling them with lead or something else heavy.

Keith Cress
kcress -
 
I must have blown past the part where energy was required at some point to get the cars back UP the hill.

Before I watched the video, though, I was trying to imagine how a system like this would work. I was imagining box cars full of water, running downhill in the same fashion as the video. However, in MY version, I imagined them emptying the water at the bottom of the hill so the cars would be significantly lighter to pull back up the hill. How are the cars filled with water, you ask? Snowfall at the top of the mountain. Getting the snow to melt for space efficiencies wasn't quite worked out in my plan yet.

Dan - Owner
URL]
 
Top of hill is coal mine. Bottom of hill is coal fired power plant. Neat.
 
It's Runzoni...

Runzoni downhill...

Dik
 
The idea is not to create energy, it's to store excess wind & solar energy and then make it available when the sun don't shine and the wind don't blow. There are not than many locations where pumped storage is possible and then you have to build dams, flood valleys, deal with droughts, floods, and fish kill etc. This would work anyplace you have a hill. But every car has it's own MG set and you would need tens of thousands of them to store meaningful amounts of energy. Looks very expensive to me.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
 
The videos that I saw were using large blocks of concrete as the 'ballast'. And these so-called 'railroad' cars were purpose-built for this task, each with their own electric drive and regenerative 'braking' system, and were attached to a 'third rail' where the power would be transferred, both when it was going up and then while coming back down the long grade. Also, there were what looked like hundreds of these 'rail-cars' setting on parallel tracks, and of course the whole thing was intended to be operated automatically, running the 'cars' up the grade when excessive power was available from the grid and then letting them roll back down when there was a need to supply additional power back to the grid.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
The loop efficiency of EVs storing regen braking and then using it again is normally quoted as 60%. There are good reasons why that figure is low, and I think 80% would be achievable. The interesting thing about 'free'-ish energy is that efficiency in the normal engineering sense doesn't matter, bang per buck is far more important.

For instance a wind generator that is only 80% as efficient at extracting wind energy as a competitor that costs 30% more is actually going to make more sense.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Greg,

60% would be for regen braking charging a battery or supercapacitor, then discharging it through the motor when the energy is used, correct?

Whereas the grid-connected storage concept does not have the battery/capacitor charge/discharge step, with its associated losses.
 
You don't need many MG units, as each can haul a number of loaded cars.
If you wanted to you could limit the total number of cars by unloading at the top and sending empty cars back down for another trip.
Just like with pumped storage the cost/eff of the initial 'charging' is irrelevant, the power is worth zero anyway since there is no other use for it. Storing as much as possible, and being able to recover it on demand is the issue. And to scale up you need rail cars and rock, not too hard.

I love supercapacitor talk, since the max recoverable power is 50%. It isn't hard to beat that.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
 
The video showed each car with a MG and said they used 800 cars for the small pilot project so I don't think they are sending them up or down empty but that would increase capacity. You would need twice as much track for two way traffic but that would be a minor cost.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
 
It's not uncommon for locomotives to be weighed down with concrete to increase tractive effort now.

Tank cars might be a little better than box cars for liquids, but loading and unloading would eat into operating the trains.

Question is if this would be an AC system or DC system requiring an inverter. And if it is an AC system, would you have three collector rails?

Also what is the cost of replacing wearable parts?
 
They mentioned 'third rail' and not 'rails' so I'd guess DC. Also I could see where a small-ish battery bank could reduce sags and the discontinuities between generating and storing. DC would allow a pretty standard VFD style DC bus with batteries as the buffer. Running DC also avoids all the speed/frequency issues.

Keith Cress
kcress -
 
The power cost is very large factor in the overall econimics of storage. While there may be a few hours a year of zero cost(or even negative cost) power, a more typical daily swing on the USA west coast is $15/MWhr off-peak and $35/MWhr on peak.
 
I don't know if I'm repeating myself, here's an invaluable source of data on the Australian energy market. I've linked to the instant view, but there is a lot of data in the other tabs there


Over the past couple of days the price paid per MWh went from $74 to $268 in NSW. At one point in SA it was -$545



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Status
Not open for further replies.

Similar threads

Tomfh
  • Question
Silo Collapse, Shoalhaven River Australia
Replies
7
Views
2K
human909
human909
Jordonlaw
  • Locked
  • Question
Building Collapse in South Africa
Replies
4
Views
287
Andries
Andries
MJCronin
  • Locked
  • Question
Fatal explosion and fire at blending plant in Australia - October 12, 2023
Replies
0
Views
120
MJCronin
MJCronin
SFCharlie
  • Question
Miami Beach, Champlain Towers South apartment building collapse, Part 19 27
5 6 7
Replies
120
Views
7K
NOLAscience
NOLAscience
Alistair_Heaton
  • Question
Australian Bridge
Replies
2
Views
631
JohnRBaker
JohnRBaker

Part and Inventory Search

Sponsor

Back
Top Bottom