Energy infrastructure

antoinolachtnai · 14-04-2021 12:05pm

Will higher winds be an issue for stability of the floating platform?

Are the floating platforms deep?

Peregrine · 14-04-2021 12:34pm

Sam Russell wrote: »

I am not surprised at such a low figure.

Would a fuel cell be a better way of using it?

Almost all of the current (limited) hydrogen use in transport is through fuel cells.

cnocbui · 14-04-2021 1:02pm

Peregrine wrote: »

Almost all of the current (limited) hydrogen use in transport is through fuel cells.

Andrew Forrest, Australia's richest person, is on a substantial green energy focussed push at the moment. He is currently big on hydrogen and is looking to establish a large gas power station that will be built with turbines that can be switched to hydrogen when the build out of his vast solar arrays in Australia's north happens, which are also aiming for liquid hydrogen exports at scale. Looks like politicians may block his plans. So it looks like hydrogen will be used to replace or supplement gas in turbines when it's being produced in bulk.

A peculiar byproduct of the current global terror of CO2 is that other environmental concerns like habitat destruction resulting from 150² km of solar panels doesn't crack a mention or concern anyone.

tom1ie · 14-04-2021 1:19pm

cnocbui wrote: »

Andrew Forrest, Australia's richest person, is on a substantial green energy focussed push at the moment. He is currently big on hydrogen and is looking to establish a large gas power station that will be built with turbines that can be switched to hydrogen when the build out of his vast solar arrays in Australia's north happens, which are also aiming for liquid hydrogen exports at scale. Looks like politicians may block his plans. So it looks like hydrogen will be used to replace or supplement gas in turbines when it's being produced in bulk.

A peculiar byproduct of the current global terror of CO2 is that other environmental concerns like habitat destruction resulting from 150² km of solar panels doesn't crack a mention or concern anyone.

Is the ground on which the solar panels is due to be placed, already desert?
Or are they cutting down forest to site these panels?

cnocbui · 14-04-2021 1:38pm

tom1ie wrote: »

Is the ground on which the solar panels is due to be placed, already desert?
Or are they cutting down forest to site these panels?

It's low scrub. As with many places, Australias deserts are not devoid of vegetation. I don't think the proposed areas are technically deserts anyway. The problem is the panels put the vegetation under them in permanent shadow. If the vegetation dies off, I suspect there could be considerable soil erosion problems given the sometimes substantial monsoonal tropical downpours in summer.

cruizer101 · 14-04-2021 1:43pm

antoinolachtnai wrote: »

Will higher winds be an issue for stability of the floating platform?

Are the floating platforms deep?

According to a video linked earlier:
The base bit that is mostly below water is 90m long and 14m diameter and weighs 3500 tonnes they then fill it with 8000 tonnes of ballast, and it still floats so they are fairly big chonky things and I would imagine fairly stable.
They are also tethered to the sea bed in some way.
The scale of turbines is hard to imagine as normally viewed from afar, and I think those ones aren't event the planned full size ones.

I'm curious how they deal with rotation/twisting though as I can't see an obvious rotational stabilizers, the tethers would do some but I imagine there is a certain give in them which would allow for rotation out of the direct line of wind.

I'm sure they have done all their sums anyway.

riddlinrussell · 14-04-2021 1:45pm

cnocbui wrote: »

It's low scrub. As with many places, Australias deserts are not devoid of vegetation. I don't think the proposed areas are technically deserts anyway. The problem is the panels put the vegetation under them in permanent shadow. If the vegetation dies off, I suspect there could be considerable soil erosion problems given the sometimes substantial monsoonal tropical downpours in summer.

Dry environments in general suffer from a perception of either being 'barren' or anything living there is considered 'tough' and therefore resistant to changes. Often there is a delicate ecological balance in such areas and many plants and animals are highly specialised to the conditions, so changes can totally destroy an environment.

bk · 14-04-2021 3:22pm

riddlinrussell wrote: »

Dry environments in general suffer from a perception of either being 'barren' or anything living there is considered 'tough' and therefore resistant to changes. Often there is a delicate ecological balance in such areas and many plants and animals are highly specialised to the conditions, so changes can totally destroy an environment.

On the other hand solar panels can give shade that can help plants and animals thrive and for the ecology to grow.

I haven't looked into the details of Australia, but I've seen projects in desert areas of the US where they have seen great improvements in ecological diversity under solar panels and even extending to surrounding areas.

Keep in mind that the outback has already been greatly impacted by man, massive damage has already been done by cattle farming and by humans encroaching on the outback and the resulting bush fires.

Of course they need to be careful about the placement of solar panels and how they integrate with the existing ecology, but if done right, they can actually be a great net benefit.

riddlinrussell · 14-04-2021 3:27pm

bk wrote: »

On the other hand solar panels can give shade that can help plants and animals thrive and for the ecology to grow.

I haven't looked into the details of Australia, but I've seen projects in desert areas of the US where they have seen great improvements in ecological diversity under solar panels and even extending to surrounding areas.

Keep in mind that the outback has already been greatly impacted by man, massive damage has already been done by cattle farming and by humans encroaching on the outback and the resulting bush fires.

Of course they need to be careful about the placement of solar panels and how they integrate with the existing ecology, but if done right, they can actually be a great net benefit.

Oh definitely, if its an area that has been effectively 'dust bowled' by overgrazing or something then this could be part of a recovery solution, moving into a 'virgin' desert with a load of solar panels would have negative effects though.

cnocbui · 14-04-2021 4:27pm

bk wrote: »

On the other hand solar panels can give shade that can help plants and animals thrive and for the ecology to grow.

I haven't looked into the details of Australia, but I've seen projects in desert areas of the US where they have seen great improvements in ecological diversity under solar panels and even extending to surrounding areas.

Keep in mind that the outback has already been greatly impacted by man, massive damage has already been done by cattle farming and by humans encroaching on the outback and the resulting bush fires.

Of course they need to be careful about the placement of solar panels and how they integrate with the existing ecology, but if done right, they can actually be a great net benefit.

It's hardly a great argument that activity X has damaged the environment so it's of no consquence if activity Y is allowed to ahead and further damage the environment. The aboriginies had been regularly burning the north of Australia, for the past 60,000 years.

Do you have a link for that biodiversity improvement of deserts, as I'm sceptical that blocking direct sun entirely from plants adapted to it over millions of years, is going to be beneficial to them?

cnocbui · 14-04-2021 4:31pm

f7b3ac48f1125471cade3460a8661b55?impolicy=wcms_crop_resize&cropH=515&cropW=916&xPos=0&yPos=39&width=862&height=485

https://www.abc.net.au/news/rural/2020-10-20/newcastle-waters-station-nt-set-for-worlds-biggest-solar-farm/12785256
Looks like a great boon to the ecology of an arid region.

15-04-2021 9:48am

cruizer101 wrote: »

According to a video linked earlier:
The base bit that is mostly below water is 90m long and 14m diameter and weighs 3500 tonnes they then fill it with 8000 tonnes of ballast, and it still floats so they are fairly big chonky things and I would imagine fairly stable.
They are also tethered to the sea bed in some way.
The scale of turbines is hard to imagine as normally viewed from afar, and I think those ones aren't event the planned full size ones.

I'm curious how they deal with rotation/twisting though as I can't see an obvious rotational stabilizers, the tethers would do some but I imagine there is a certain give in them which would allow for rotation out of the direct line of wind.

I'm sure they have done all their sums anyway.

Spot on, the SPAR concept is well proven and provides excellent stability, the mooring system (more than likely suction anchors) provides the rotational stability.
interesting wee description here
https://www.equinor.com/en/what-we-do/floating-wind/how-hywind-works.html
But guessing by the time anything happens here they could well using much larger, >10MW turbines, small difference in installation cost for much greater power yield.

bk · 15-04-2021 11:25am

cnocbui wrote: »

It's hardly a great argument that activity X has damaged the environment so it's of no consquence if activity Y is allowed to ahead and further damage the environment. The aboriginies had been regularly burning the north of Australia, for the past 60,000 years.

The point is to help reverse damage already done.

https://www.anthropocenemagazine.org/2020/04/can-desert-plants-and-solar-panels-live-in-harmony-sometimes-yes/

https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.3089

These results demonstrate that the ecological consequences of solar development can vary over space and time, and suggest that a nuanced approach will be needed to predict impacts across desert landforms differing in physical characteristics.

So it is a complex topic, it can differ from desert to desert, it can actually be a net positive in some locations, while a negative in others.

So you need to be careful where and how you place panels. But it is certainly not a case that all solar panels in deserts are bad.

dubhthach · 18-04-2021 2:13pm

The proposed undersea cable is interesting, given the length and the sesimic issues in area. Makes ye wonder would a Ireland Spain interconnector be viable in the future.

Obviously there's already a routed selected for Fibre Optic connection between Ireland (Galway specifically) and Spain (Bilbao), which clocks in at 1,700km in length (it goes off the continental shelf)

Obviously perhaps a more direct route could be selected to cut down on that, as a comparison the current longest HVDC cable in works is the "Viking link" from the UK to Denmark.

bk · 18-04-2021 6:26pm

dubhthach wrote: »

The proposed undersea cable is interesting, given the length and the sesimic issues in area. Makes ye wonder would a Ireland Spain interconnector be viable in the future.

Any particular reason to go to Spain, rather then the much shorter route to France?

If you are going to go long distance, Norway with it's lovely hydro power, would be a better bet. 1,100km from Donegal to Bergen, though that would go through UK sea territory.

BTW Cork to France looks to be about 450km, but that goes through UK territory too. Actually that WINS cable looks to take that strange route to specifically avoid UK territory. Interesting.

tom1ie · 18-04-2021 7:35pm

bk wrote: »

Any particular reason to go to Spain, rather then the much shorter route to France?

If you are going to go long distance, Norway with it's lovely hydro power, would be a better bet. 1,100km from Donegal to Bergen, though that would go through UK sea territory.

BTW Cork to France looks to be about 450km, but that goes through UK territory too. Actually that WINS cable looks to take that strange route to specifically avoid UK territory. Interesting.

Celtic interconnector goes to France so I presume we would be tapping into a different coutries grid in case the French grid faced problems or something similar like that.

bk · 18-04-2021 10:27pm

tom1ie wrote: »

Celtic interconnector goes to France so I presume we would be tapping into a different coutries grid in case the French grid faced problems or something similar like that.

Mainland Western Europe is basically all one synchronous electrical grid:

https://en.wikipedia.org/wiki/Synchronous_grid_of_Continental_Europe

cnocbui · 18-04-2021 11:32pm

bk wrote: »

Any particular reason to go to Spain, rather then the much shorter route to France?

If you are going to go long distance, Norway with it's lovely hydro power, would be a better bet. 1,100km from Donegal to Bergen, though that would go through UK sea territory.

BTW Cork to France looks to be about 450km, but that goes through UK territory too. Actually that WINS cable looks to take that strange route to specifically avoid UK territory. Interesting.

The cable clearly seems to be taking a route determined by sea bed geography, in particular, taking advantages place with a gradual decline to the relatively flat abysal sea floor.

Further research indicates that the route has nothing to do with avoiding UK territory but is solely concerned with security of the cable and minimising the necessity of burying it in a trench, which would be required at the shallower depths of a more direct route:

The WINS cable system is 1774 km in length with the majority of the system routed in deep water off the continental shelf. The objective of this routing is to minimize installation difficulties and maximizing security of the system during its life. Of the 1774 km overall length only 325 km of the system is in water depth of less than 1500m.
...
The general criteria for secure sub-sea cable installation are that the cable needs to be trenched to a depth of 500mm to 600mm up to the 1500 metre water-depth. Beyond the 1500 metre water-depth the cable can be surface laid on the sea-floor. 3.9Even in the case of the shallower sections,the water depths are of the order of 200 to 250 metres except at the approaches to the landfalls where sea bed conditions are expected to facilitate secure cable trenching with adequate depth of cover.

file:///Users/anon/Downloads/79626_e4353ba6-c4fd-4a4b-b462-1fdcb83e68d8.pdf

bk · 18-04-2021 11:46pm

Fair enough cnocbui, just a coincidence so that it just avoids UK waters, which of course now that I think of it, follows the continental shelf.

Having said that the Celtic Interconnector appears to go right through these UK waters, so that doesn't seem to be an issue and they seem to just take the most direct route.

dubhthach · 20-04-2021 9:45am

bk wrote: »

Any particular reason to go to Spain, rather then the much shorter route to France?

If you are going to go long distance, Norway with it's lovely hydro power, would be a better bet. 1,100km from Donegal to Bergen, though that would go through UK sea territory.

BTW Cork to France looks to be about 450km, but that goes through UK territory too. Actually that WINS cable looks to take that strange route to specifically avoid UK territory. Interesting.

Diversity of interconnect routes? Obviously Spain and France are in same Grid market.

Generally with Fibre networks if Latency isn't a major issue then ye want to get deep as soon as possible to avoid having to use 'hardened cable' that has to be buried in shallower water to avoid damage from trawlers.

Most of cable will be made up of unarmoured cable like on left in below image:

as opposed to:

close-up-of-a-fibre-optic-undersea-submarine-cable-2.jpg

In case of WINS cable it's main point is to provide a missing link in redudant transatlantic system. As there are already cables that cover 'US to Bilbao' and 'US to West of Ireland'. If there is break in either cable system the WINS cable will be used to reroute the traffic over the other cable system.

bk · 20-04-2021 11:56am

dubhthach wrote: »

Diversity of interconnect routes? Obviously Spain and France are in same Grid market.

If diversity was the goal, then connecting to Norway would be the better option, as that would give you a connection to the Nordic grid, which is separate from the Continental European grid, which we will already have a connection to once the Celtic Interconnector to France is built.

Interestingly there is an interconnector currently being built from the UK to Iceland, which is over 1,000km long, which would show that a connection to Norway could be done.

Also Norway are building an interconnector to the Shetland Islands.

Banana Republic 1 · 20-04-2021 3:04pm

bk wrote: »

If diversity was the goal, then connecting to Norway would be the better option, as that would give you a connection to the Nordic grid, which is separate from the Continental European grid, which we will already have a connection to once the Celtic Interconnector to France is built.

Interestingly there is an interconnector currently being built from the UK to Iceland, which is over 1,000km long, which would show that a connection to Norway could be done.

Also Norway are building an interconnector to the Shetland Islands.

A connector that long would have to be DC wouldn’t it ?

dubhthach · 20-04-2021 4:01pm

Banana Republic 1 wrote: »

A connector that long would have to be DC wouldn’t it ?

All modern subsea interconnectors are HVDC (High Voltage DC), even the short ones across the English channel.

gjim · 20-04-2021 10:00pm

dubhthach wrote: »

All modern subsea interconnectors are HVDC (High Voltage DC), even the short ones across the English channel.

Not just subsea interconnectors - all connections between unsynchronised grids has to be done by DC.

Capt'n Midnight · 20-04-2021 11:31pm

gjim wrote: »

Not just subsea interconnectors - all connections between unsynchronised grids has to be done by DC.

Off topic

in Japan they have this big spiny thin to join two regions , big rotary electric thing kinda like a dynamotor with two different numbers of coils so one end is 50 Hz and the other is 60 Hz , but they are synchronised.

On topic

An undersea cable is a capacitor formed by the electrical conductor and it's insulation and electrically conductive seawater. Reactance is measured in Ohms Xc = 1/(2πfC) means AC leaks electricity like a sieve over long distances.

In comparison air isn't a good conductor and overhead conductors can be kept far apart. European companies can build a 1.1 Million volt line over 3,000Km long in China. So with really good insulation you could possibly do the same under water. Just takes lots of money.

bk · 21-04-2021 11:17am

Capt'n Midnight wrote: »

In comparison air isn't a good conductor and overhead conductors can be kept far apart. European companies can build a 1.1 Million volt line over 3,000Km long in China. So with really good insulation you could possibly do the same under water. Just takes lots of money.

There is a project to build a 4,500km interconnector between Australia and Singapore, called the Sun Cable:

https://suncable.sg/

It also includes a massive solar farm and battery farm in Australia.

By comparison, Ireland to Spain or Ireland to Norway would be quiet doable.

Having said that, for Spain, it probably just makes more sense to build a second Interconnector to France and have the French build more AC interconnection with Spain and Italy if needed.

Likewise, for Norway, would make more sense to go via Scotland, leaving aside Brexit issues.

23-04-2021 11:05am

gjim wrote: »

Not just subsea interconnectors - all connections between unsynchronised grids has to be done by DC.

HVDC is more efficient than AC after about 60km or so and is bi-directional, can transmit power either way.

bk wrote: »

If diversity was the goal, then connecting to Norway would be the better option, as that would give you a connection to the Nordic grid, which is separate from the Continental European grid, which we will already have a connection to once the Celtic Interconnector to France is built.

Interestingly there is an interconnector currently being built from the UK to Iceland, which is over 1,000km long, which would show that a connection to Norway could be done.

Also Norway are building an interconnector to the Shetland Islands.

Norway is already connected to the European electricity market, NorNed, 2008 or so, was the longest subsea power cable at the time.

gjim · 23-04-2021 3:42pm

323 wrote: »

HVDC is more efficient than AC after about 60km or so and is bi-directional, can transmit power either way.

I think you've a typo there? It's at least 10 times that distance before you break even in terms of cost/efficiency.

Norway is already connected to the European electricity market, NorNed, 2008 or so, was the longest subsea power cable at the time.

Yeah but I think bk's point was connecting to Norway gives you diversification as its grid is independent of the main European one. Spain and France are on the same grid so a 2nd connection to Spain gives you redundancy but not diversification.

bk · 23-04-2021 7:06pm

gjim wrote: »

Yeah but I think bk's point was connecting to Norway gives you diversification as its grid is independent of the main European one. Spain and France are on the same grid so a 2nd connection to Spain gives you redundancy but not diversification.

Yep, spot on, I'm aware that Norway and the other Nordic countries have multiple interconnectors to mainland Europe now. But they are all HVDC interconnectors and therefore the Nordic grid is still separate from the continental European grid. Much in the same way that the all Ireland grid is still separate from the UK grid, despite HVDC interconnectors between us. Our similar between UK and continental Europe.

Apogee · 23-04-2021 8:05pm

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