The future of energy generation and storage

[SirRumpole]

Seawater pumped hydro being investigated for SA.

https://theconversation.com/snowy-h...awater-hydro-could-help-south-australia-74442

 

[moXJO]

Seawater pumped hydro being investigated for SA.

https://theconversation.com/snowy-h...awater-hydro-could-help-south-australia-74442

Sounds like a better idea then battery storage and a lot longer lasting for the money

 

[Smurf1976]

Also the possibility of long term drought which is not unknown.

Given that, would it be more sensible to build pumped hydro on the coast, pumping sea water ?

Hydro power stations run a lot of water through them but they don't consume it as such.

There's about 32,500 litres per second going through Tarraleah (Tas) at the moment. That's 32,500 litres per second going into the two pipelines at the Tarraleah forebay, the same volume then split into 6 penstocks at the top of the hill and the same volume comes out of the power station into Lake Liapootah. Actual consumption of water is literally zero apart from a minor amount of evaporation and losses in the canals between the dam and the forebay. Every drop of water that goes in is available for other uses (like the 6 other power stations and then Hobart's water supply plus industrial and irrigation use) downstream.

So conventional hydro works by moving water from one place to another at lower elevation with nature (ultimately solar energy) doing the pumping via natural rainfall.

Only difference with a pumped storage scheme is that the pumping up hill is done by pumps as such but there's still no water being consumed apart from evaporation from the lakes.

It's not totally impossible I suppose, but if we ever get a drought bad enough to dry major lakes up due to evaporation then Australia is going to have far bigger problems than electricity. We'd have abandoned practically every rural town and even places like Canberra long before it came to that point. So not totally impossible but certainly unprecedented and if it does happen then electricity will be well down our list of concerns at that point.

In contrast a coal or nuclear plant, plus some gas-fired plants, do actually consume considerable amounts of water in order to operate. In a worst case drought scenario they'd have come to a halt well before we lost all the water in a pumped storage scheme.

So overall it's not totally impossible but it's extremely unlikely.

 

[Smurf1976]

Sounds like a better idea then battery storage and a lot longer lasting for the money

Absolutely.

Tas is still running a hydro station built over a century ago and it's working today just as well as it did when new. It's running right now actually. Likewise Tarraleah (1938) also running at the moment and we've got another 5 stations from the 1950's also all still fully operational today with 3 of them running at the moment.

As for batteries well I'll put it this way. Just about everyone on this forum would own devices which some form of rechargeable battery. Your own experience over the years has likely involved batteries failing and that's the reality of what happens. When you've got a chemical reaction involving corrosion at work then lifespan is ultimately finite no matter how well it's designed and maintained.

Hydro - life is measured in decades and can easily exceed a century or longer.

Batteries - life is measured in years and if it gets to a decade you're doing pretty well.

 

[Smurf1976]

Basslink (Tas - Vic) disconnected for a planned 5 day outage at 4am this morning.

No power supply problems are expected in Tas since we've got plenty of generating capacity and water to run it with. In Vic the weather is forecast to be mild enough to not be a concern.

Coincidentally the gas price has dropped recently so in Tas we're running one of the open cycle gas turbines, the more efficient one, as well as the CCGT but that's for purely economic reasons. The hydro system would easily meet demand without running gas but there's no point using more water now if someone's willing to sell gas at a price that makes more sense to use that instead and keep the water for use at some future time. The 3 less efficient gas turbines aren't being run, since their lower efficiency means the economics don't stack up, but they could be run if the gas price dropped further or as a backup if something went wrong.

So all good there. Now AGL just have to move their great big 2100 tonne mining machine in Vic and then the cable can be put back up. With a top travel speed of 0.5 km/h they won't get done for speeding that's for sure. Looks like a pretty massive task though.

 

[Smurf1976]

Some info on what's going on with the machine being moved:

http://www.latrobevalleyexpress.com.au/story/4479008/road-trip-of-epic-proportions/

A 19km trip that's expected to take almost a month.

 

[Value Collector]

 

[moXJO]

I wonder how the batteries do in extreme heat?
Can't say I'm sold on the tech just yet.

 

[Value Collector]

I wonder how the batteries do in extreme heat?
Can't say I'm sold on the tech just yet.

I know they have a heat management system in their car batteries, I would imagine if heat were a problem they would have a similar system to deal with it.

 

[SirRumpole]

I know they have a heat management system in their car batteries, I would imagine if heat were a problem they would have a similar system to deal with it.

A lot of fans that consume all the power the batteries put out.

Tsk, tsk, cynic.

 

[Value Collector]

A lot of fans that consume all the power the batteries put out.

Tsk, tsk, cynic.

Their car battery is liquid cooled, so I guess the stationary systems would be too, without the need to be light weight, you could actually have a thermo syphon convection based cooling system, that only needed a fan in extreme cases.

 

[SirRumpole]

I wonder when someone will rediscover the Stirling engine that just needs a thermal gradient to operate.

There seems to be a lot of heat going to waste.

 

[Value Collector]

 

[sptrawler]

https://cleantechnica.com/2017/01/31/tesla-needs-just-three-months-complete-worlds-largest-grid-storage-facility/https://cleantechnica.com/2017/01/31/tesla-needs-just-three-months-complete-worlds-largest-grid-storage-facility/

That is a lot of individual cells, that will need some sort of management, at the end of their useful life.
Just another take on it, I think Rumpole's idea of pumped storage has a lot more merit, at this point in time.
But hey, it's anyone's guess, which way this energy debacle will fall.

However 6,336,000 cells, seems like a lot to me.

 

[moXJO]

https://cleantechnica.com/2017/01/31/tesla-needs-just-three-months-complete-worlds-largest-grid-storage-facility/https://cleantechnica.com/2017/01/31/tesla-needs-just-three-months-complete-worlds-largest-grid-storage-facility/

That is a lot of individual cells, that will need some sort of management, at the end of their useful life.
Just another take on it, I think Rumpole's idea of pumped storage has a lot more merit, at this point in time.
But hey, it's anyone's guess, which way this energy debacle will fall.

However 6,336,000 cells, seems like a lot to me.

Look up "flow batteries" The tech can be scaled up very easily. Might still have some cost problems. Heard a little bit about them on the radio today.

 

[sptrawler]

Battery technology is trying to bridge the gap of energy density, and charge time, they are both a major hurdle and overcoming it is proving a massive problem.
Capacitor technology has the charge time advantage, battery chemistry has the energy density, combining the two is the problem which currently is the stumbling block.

 

[Value Collector]

Just another take on it, I think Rumpole's idea of pumped storage has a lot more merit, at this point in time.
But hey, it's anyone's guess, which way this energy debacle will fall.

However 6,336,000 cells, seems like a lot to me.

There is huge limitations o pumped storage.

you can't just build a dam system anywhere you want, however you can install batteries pretty much anywhere, in any scale.

and pumped storage is really just a hydro power plant, you are just really adding generation capacity, and generating capacity isn't the problem, the problem is being able to time shift the power, e.g. store renewable energy and use it later in the day.

 

[SirRumpole]

the problem is being able to time shift the power, e.g. store renewable energy and use it later in the day.

That's exactly what both pumped storage and batteries do. Neither is a generation system, they both need power to 'recharge' , but they can both release the power when needed.

There is no conceptual difference between pumped storage and batteries, the difference is in the technology used.

 

[Value Collector]

Neither is a generation system, they both need power to 'recharge' , but they can both release the power when needed.

.

What is the difference between pumped storage and a regular hydro generation?

I can't see a difference except that the pumped storage dam is built in a poor location that requires refilling by pump rather than natural rain fall.

How fast do you reckon you can setup a decent sized pumped storage dam?
Where can you put it?

Batteries can go anywhere, included in existing substations or even at peoples houses.

 

[SirRumpole]

What is the difference between pumped storage and a regular hydro generation?

Pumped hydro recirculates water and is therefore not dependent on rainfall to fill the dam.

There is obviously a place for batteries. You can't build pumped hydro for a house or small business. It's a matter of how well they scale up to power cities. They don't last forever and eventually need to be replaced. In the absence of disasters like earthquakes, pumped hydro will last decades -> centuries.