Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Australian government approves AAPowerLink project to export solar to Singapore

pv-tech.org

Post reply on HN
Print view View original

171–180 of 299 posts

Re: Australian government approves AAPowerLink project to export solar to Singapore

#171

Post by philipkglass »

bigiain wrote: post #96
gonzo41 wrote: post #19

Earlier quoted context omitted.

Data Centers, Green Steel production. Power == Opportunities. This is such a massive win for the environment.

I did a little back of the envelope calculation in a discussion here last week: https://news.ycombinator.com/item?id=41220499 If Australia refined _all_ of the 40,000kt of Bauxite we export each year into "frozen electricity" Aluminium, that'd only require about 600GWh, or about 4% of the 1.7GW 24x7, or 15,000GWh per year this would send to Singapore. Large datacenter are in the 100MW sort of range, so only single di…

Approximating bauxite as pure aluminum oxide [1], 40 million tons of bauxite contains about 21 million tons of aluminum. A ton of aluminum takes about 14 megawatt hours of electricity to produce [2]. That would be about 294,000,000 megawatt hours (294,000 gigawatt hours, or 294 terawatt hours) to turn Australia's bauxite exports into aluminum. Australia could easily double its electricity production/consumption to refine bauxite into aluminum metal instead of exporting the bauxite.

[1] https://en.wikipedia.org/wiki/Aluminium_oxide#Production

[2] https://www.mining.com/web/aluminum-price-hits-13-year-high-...

Re: Australian government approves AAPowerLink project to export solar to Singapore

#172

Post by richrichie »

eru wrote: post #93
richrichie wrote: post #17

Earlier quoted context omitted.

Singapore with a native population of about 4 million has reserves of about $1 trillion. They can afford to splurge to claim green/net-zero status. Shopping calculations for them need not be about economic cost benefit analysis.

> Shopping calculations for them need not be about economic cost benefit analysis. But there's also no good reason not to apply cost/benefit analysis. > Singapore with a native population of about 4 million has reserves of about $1 trillion. They can afford to splurge to claim green/net-zero status. Of all numbers to bring up here, why did you pick foreign exchange reserves? GDP or wealth might be more relevant?

No one applies economic cost benefit analysis to buy a Louis Vuitton bag for $50,000. Prestige, signalling, membership to exclusive club, etc dominate the consideration.

Reserves are cash in hand and represent immediate and hard spending power.

Re: Australian government approves AAPowerLink project to export solar to Singapore

#173

Post by immibis »

goodcanadian wrote: post #162
ikekkdcjkfke wrote: post #110

Earlier quoted context omitted.

Would they be using AC or DC? I heard that very long cables using AC can be more lossy

It doesn't seem like anyone directly answered your question. As far as I am aware, all long distance undersea power cables are high voltage DC. I believe this has to do with the efficiency of power transfer over long distances.

AC loses power by inductively and capacitively coupling to nearby objects. It's manageable at medium distances above ground, cheaper than a pair of converter stations. However, water is much more conductive than air and losses from an underwater AC cable would be much greater.

Re: Australian government approves AAPowerLink project to export solar to Singapore

#175

Post by cgravill »

duckmysick wrote: post #129
eru wrote: post #85

Earlier quoted context omitted.

Nuclear is held to a much higher safety standard (eg in terms of deaths per Joule) than any other form of electricity production. And that includes photovoltaic! Nuclear is so safe--even fully factoring in the accident at Chernobyl--that people very occasionally falling off rooftops when installing solar panels is a bigger health hazard per Joule produced.

How much bigger of a health hazard is manufacturing/installing solar panels compared to nuclear? Let's say, per one terawatt-hour of produced energy, how many people die doing each?

Some comparisons of power generation by deaths here: https://ourworldindata.org/safest-sources-of-energy

Re: Australian government approves AAPowerLink project to export solar to Singapore

#176

Post by joha4270 »

graemep wrote: post #158
joha4270 wrote: post #50

Earlier quoted context omitted.

Real projects has a way of encountering unexpected troubles in a way thay paper ones dont. On top of that there is the energy security problem, even if Morocco is less likey than Russia to try and play tricks. I wish them all luck, but we can't forget the advantages projects has before leaving Excel.

> On top of that there is the energy security problem, even if Morocco is less likey than Russia to try and play tricks. A cable this long will be vulnerable to attack by any country that has submarines. How is it going to be guarded?

Or you know, a cargo ship that can drag an anchor along the seabed.

And that guarding, probably by thoughts and prayers, aka diddly squat.

Re: Australian government approves AAPowerLink project to export solar to Singapore

#177

Post by jaidan »

ikekkdcjkfke wrote: post #110
londons_explore wrote: post #37

Earlier quoted context omitted.

Power cables are getting cheaper and cheaper. The expensive part used to be the voltage conversion stations at the ends, but with mass production of MOSFETs for EV's these have now become far cheaper than the JFET's and other exotic silicon that used to be used. In turn, that means voltages can be higher, letting one use more of the cheaper PVC or XLPE insulating material and less expensive aluminium for the same amo…

Would they be using AC or DC? I heard that very long cables using AC can be more lossy

The problem with long distance AC is the reactive power component caused by the capacitance, and the voltage rise caused by the Ferranti effect.

The reactive component has significant impact on the generation equipment and grids. It also causes the Ferranti effect, where the voltage along the cable rises. This can make managing the voltage within the cable difficult because at no load, the load end has a higher voltage than the source, and when loaded, the middle of the cable has a higher voltage than both ends.

During stable operation these effects can be managed with Statcoms, shunt reactors and voltage regulation tap changers. However during transient operation you will be relying upon the static protective devices such as surge arrestors, depending on how large the transient is.

DC transmission does not suffer from the same reactive power component and has less losses, but it does require large convertor stations at both ends.

Re: Australian government approves AAPowerLink project to export solar to Singapore

#178

Post by qbxk »

vlasky wrote: post #139

I'm Aussie and I can't believe this Sun Cable project is being taken seriously by our government. The longest submarine power cable in the world - the Viking Link - is a mere 756 km long and cost US$2.2bn to build. Sun Cable calls for a 4,200km submarine cable to be built! I do not expect the construction cost to scale linearly and I shudder to imagine the maintenance difficulties and expenses. Back in December 2015,…

They just began running a team of barges down Lake Champlain to lay 546km of cable from Quebec to NYC for $4.5B

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

Re: Australian government approves AAPowerLink project to export solar to Singapore

#179

Post by contingencies »

BillSaysThis wrote: post #163
ikekkdcjkfke wrote: post #110

Earlier quoted context omitted.

Would they be using AC or DC? I heard that very long cables using AC can be more lossy

This is Australia, it's AC/DC!

For the confused that is a reference to https://en.wikipedia.org/wiki/AC/DC

Amusingly (IMHO), The band's line-up remained the same for 20 years until 2014 when Malcolm retired due to early-onset dementia, from which he died three years later; additionally, Rudd was charged with threatening to kill and possession of methamphetamine and cannabis. Stevie, who replaced Malcolm, debuted on the album Rock or Bust (2014). On the accompanying tour, Slade filled in for Rudd. In 2016, Johnson was advised to stop touring due to worsening hearing loss. So a rocker's fate: forgot what planet they were on, went mad on drugs becoming threats to society, lost their hearing, or kept touring indefinitely with a changing lineup cashing in on past glories.

Similar period https://www.youtube.com/watch?v=XfR9iY5y94s https://en.wikipedia.org/wiki/Down_Under_(song)

Re: Australian government approves AAPowerLink project to export solar to Singapore

#180

Post by tim333 »

londons_explore wrote: post #161
coryrc wrote: post #160

Earlier quoted context omitted.

> The expensive part used to be the voltage conversion stations at the ends, but with mass production of MOSFETs for EV's these have now become far cheaper than the JFET's and other exotic silicon that used to be used. Why do you believe these things are related? HVDC lines operate in the hundreds-of-kilovolts range. For example, https://en.wikipedia.org/wiki/Basslink operates at 400kV. There are no MOSFETs or JFETs…

Semiconductors are stackable to get higher voltage. They're parallelizable for more current. Cost scales linearly with voltage and current, and is therefore constant WRT to system power.

Apparently they use thyristors https://en.wikipedia.org/wiki/Thyristor#HVDC_electricity_tra...

https://en.wikipedia.org/wiki/HVDC_converter#Thyristor_valve...

Post reply on HN