The h Bar

12:00 AM

@PM2Ring who says you have to build your regenerative power plants away of the population centers? Most regenerative energy power plants can be scaled and built around where they are needed

i am trying to remember the name of some of those regenerative power plants which make use of this long pipe inside the ocean method

i think it is this method en.wikipedia.org/wiki/Ocean_thermal_energy_conversion

Australia should be perfect for this kind of plants yet there is only one currently in Japan according to this article

PM 2Ring

Our attitude to renewables is mixed. OTOH, we have stuff like the Snowy Mountains Scheme, and did lots of solar research a few decades ago. In more recent times, a left-wing federal government gave big incentives to use solar energy. But when they introduced a carbon emissions trading scheme they got kicked out & replaced by our current right-wing government, and the solar incentives have been largely eliminated.

It doesn't help that we have huge reserves of coal & gas. And as you might guess, there are strong links between the big mining companies & the parties in our ruling right-wing coalition.

pZombie

It's a pity because Australia is such a perfect place to live currently, considering the low population density. 3 per square kilometer last time i checked. In other places, no matter how much regenerative energy sources you add, it will never be enough because of the population exploding

PM 2Ring

@pZombie Maybe, although if you look at the map our ocean temperature differential is low, except in the very northern parts, which have a small population.

pZombie

Europe is a lost cause. Everything is already overpopulated. If Germany for example had the same population density as Australia, it would produce more than 10 times the energy it needs just from regenerative energy sources

PM 2Ring

We get huge amounts of rain in the Top End, but it's not economical to use it for hydro power. Heck, it's not even economical to pump water from the north to the drier parts of the continent.

pZombie

12:10 AM

Yet ever more people are pushed into Europe whereas Australia with a more than 30x lesser population density allows only very few selected in

ACuriousMind

People have been warning of the Malthusian trap of overpopulation for centuries, and yet we're still here, still happily populating. Technology can outpace pessimistic predictions - who at the beginning of the 20th century could have predicted the Green Revolution?

PM 2Ring

Most of our population is on the coast. We have lots of desert. And in some parts, you still couldn't grow stuff if you magically supplied water due to the huge levels of salt in the soil. Large parts of our marginal areas have been ruined by badly managed irrigation systems which have brought underground salt deposits into the water table and up to the surface.

pZombie

In my opinion, the higher the population density, the less land each of us can posses, hence people have to be squelched into mega cities which in turn lowers the quality of life. Extra pollution just being one of the problems. We don't have to live on the planet all at the same time. Just wait your turns...

PM 2Ring

There are places where people attempted to farm, having been deceived by relatively wet weather in our complex long-term weather cycles. It's hard to grow crops or even raise livestock when you can get multi-year droughts.

pZombie

@PM2Ring That's another advantage of the OTEC power plants. You generate desalinated water as a byproduct. Just add a little salt to it...

PM 2Ring

12:21 AM

One of my online friends who lives in Western Australia told us about the joy & amazement of her young kids the first time they ever saw rain. The eldest was 5 years old. And this is on the fringe of the largest population centre in that part of the country.

pZombie

I guess nothing stops one from moving to places in Australia where the weather is more to his liking. Australia certainly has enough space to accommodate it for any australian

PM 2Ring

For some reason, both Australians and new immigrants prefer to live in the handful of cities, where there's infrastructure and jobs, rather than in the middle of the desert. ;)

Of course, there are people living in our smaller cities and larger towns as well, but the infrastructure there isn't so well developed. And when the kids grow up the majority of them head to the big cities for jobs & higher education. True, some of them return, but not many.

Jake Rose

@pZombie how is Europe overpopulated?

your prediction on renewable energy ‘never’ being enough is quite flawed imo

and currently Europe isn’t in the middle of a population explosion

PM 2Ring

At least, we have decent mobile phone & internet coverage now near the population centres. But forget about high speed fibre, unless you're very close to town.

Jake Rose

12:38 AM

@pZombie I really don’t understand what you’re asking about with the torches

Sir Cumference

2:29 AM

@Blue Oh right what'd they say about the ads lol

vzn

3:24 AM

@ACuriousMind malthusianism has supposedly been "debunked" long ago. or has it? earth life support systems are all blinking red. global warming leading to extreme weather, food production decline, mass extinction (now on a geological scale), pollution, rise of "precariat" etc... so yeah there are 7B humans on the planet but wasnt malthus really inherently talking about quality of life... how many of those billions live on tiny )( subsistence wages? think he wasnt wrong, instead visionary...

dmckee

5:38 AM

@pZombie The interesting thing that is sometimes overlooked is that (at least for technologically advanced societies), high-density urban areas have a lower per capita environmental impact than rural living.

The environmentally optimal way of having lots of humans is to have almost all of them living in high-tech vertically extended urban centers, with a paltry few managing industrial scale food production on only the best arable land while the marginal land is allowed to go back to near wilderness and used mostly for recreation.

Which kinds sucks for me because I don't care for urban life, but I'm not a farmer.

John Rennie

5:51 AM

I grew up in a rural setting (Mendip hills). It's pretty, and it's a great place to be a kid, but it's a rubbish place to be for anyone older. Any decent facilities are a 20 mile drive away in the nearest large cities like Bristol or Bath.

I left at 18 to go to university and don't go back except for obligatory visiting of relatives.

dmckee

6:09 AM

I agree about the services (and just now I'm in a desert town of less than 10,000 about an hour from real services; but when I can finally bring the family out we're going to be close to that medium sized city).

My problem is that I don't care from the closeness of cities.

I've been happiest in small cities (a few hundred thousand), where you get decent shopping and simple entertainment and working internet. And I just put up with having to drive to find specialists doctors and the like.

PM 2Ring

6:23 AM

This question reminded me of Archimedes Plutonium...

PM 2Ring

8:21 AM

I have to admire this kid's tenacity. This is his 3rd or 4th attempt to post this. I just wish he'd listen to some of the advice people have been trying to give him to help improve the question.

John Rennie

10:19 AM

@dmckee That's exactly where I live. Chester has a population of around 120k. Big enough to have everything I want but small enough that a cycle ride from one edge to the other is no great ordeal.

user2723984

GR exam in 3 hours, wish me luck people

Slereah

10:59 AM

Remember, space has 3 dimensions!

PM 2Ring

They did try 2 dimensional space, but it wasn't very popular because the beer was always flat.

3

Anonymous

11:20 AM

@SirCumference Umm, what?

Shing

I would like to ask if I already have a master of science in Physics, do I have to undergo the 5 years in the PhD program from the States?

Avnish Kabaj

11:39 AM

Because 2 cameras aren't enough

The design looks good

What's the seventh dot for?

bolbteppa

12:37 PM

@Shing not here physics.tamu.edu/academics/prospective-graduates/… anyway (fast-track)

PM 2Ring

12:51 PM

I wonder if this guy really does have a uranium pellet physics.stackexchange.com/questions/457498/…

Loong

1:12 PM

Why not? We had bottles full of UO2 pellets in my group at university.

Of course not enriched uranium. ;-)

Now at work, we have almost 200 tons of enriched UO2 in form of such pellets.

But I couldn't get the actual pellets out without destroying the fuel cladding.

Hm, maybe they have some pellets of depleted UO2 at our visitor's centre.

Anonymous

1:27 PM

Motl blogged about the question on QCSE. No wonder it went to the HNQ. :P

Anonymous

Hmm, actually I'm not sure. Can't find it in the HNQ list. Maybe it was on yesterday's. But it sure has a disproportionately large number of views and upvotes now.

PM 2Ring

@Loong Oh, ok. I guess if it's a natural isotope mix, or pure U-238 oxide it's relatively safe in pellet form. But that powder is a bit of a worry.

@Loong Do you work at a reactor?

Loong

@PM2Ring Yes, don't inhale it.

PM 2Ring

Of course, if it were a pellet of Pu-238 oxide, he wouldn't need to ask how to make it produce heat. :D

Loong

The pellets don't show any number, so they probably don't contain enriched uranium.

@PM2Ring yes

PM 2Ring

1:48 PM

Although we produce lots of uranium in Australia, we don't have any nuclear power stations, just 1 research reactor, which produces medical radioisotopes. People are amazed when I tell them that coal-burning power stations produce radioactive waste.

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