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Old 2017-12-23, 18:54   #23
jasonp
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Lester Brown has written extensively on this topic; his early book 'Outgrowing the Earth' scared the hell out of me. He has a more recent work that is also a very thoughtful read.
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Old 2017-12-24, 11:20   #24
LaurV
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Talking about books, "Stand on Zanzibar" is a must to read. We remember we mentioned it here in the past during a time we were arguing in some topic about science-fiction books...
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Old 2018-05-23, 16:22   #25
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Quote:
Originally Posted by chalsall View Post
Seconded. And while not clinically diagnosed, I am definitely "in the spectrum".

I have written here before about my dyslexia. I truly have trouble understanding the spoken words "left" and "right", and what relative vectors they are supposed to mean.

If I'm driving and someone says "turn left", I will sometimes turn right. If I'm a passenger, I will sometimes say "turn left" when I really mean right. People who know me well have learnt to point, or to have me point to confirm my words match my intentions. As an aside, nothing drives me more bat-shit crazy than when I'm driving and someone says "turn right here". "There's no right turn here." "No! I mean the turn is right here!!!

But I don't consider this a handicap. I often intuitively see things in ways that others simply don't, until it is explained.

(I will leave my complete inability to understand the nuances of human interactions for a later time....)

P.S. Another attribute: "Previewing Post" many times, and then editing, before Submitting. To try to get the Language as close to correct as possible the first time. Or maybe that's a programmer's thing....
Reminds me of an old I Love Lucy episode. She and Ricky are vacationing, towing a big Airstream trailer. It being the 1950s, he was driving and she was giving directions. She says "Turn right here" and he turns, right, as she finishes "...left. Left.". It's a narrow country road and a big trailer and nowhere to turn around, leading to comedic progression. They cashed in and took gender stereotypes to the bank, laughing all the way.

As for preview post, since I do that too, it must be normal, right? ;) Checking for format, spelling, completeness, etc. seems the polite thing to do. (And it seems lately, when I put a carriage return in, it gets interpreted as two or three...)

Last fiddled with by kriesel on 2018-05-23 at 16:30
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Old 2018-05-23, 16:28   #26
kriesel
 
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Quote:
Originally Posted by VictordeHolland View Post
Let's get a back on topic:

Let's do some estimates on primary energy supply/consumption (primary energy in this context means before it is converted. So coal before it is burned for electricity, oil before it is converted to gasoline/kerosene/etc. note that hydro/renewables are not converted since they produce electricity).

Lets take some averages and extremes:
Qatar 803 GJ per capita (2013)
Lots of cheap oil and a lot of airco....

USA about 290 GJ per capita (2013 value, equals roughly ~80,000 kWh)
Big trucks, big houses, huh?

France/Germany 162 GJ per capita (2013)
Japan 150 GJ per capita (2013)
UK 125 GJ per capita (2013)
Japan and most of EU use significantly less per capita.

Hong Kong 81 GJ per capita (2013)
Low energy consumption per capita for a well-developed country
https://en.wikipedia.org/wiki/List_o...ion_per_capita

Future energy consumption estimates with current population (7.5 billion)
Worst possible scenario:
If all the 7.5 billion people would consume as much energy as Qatar/capita (
803 GJ * 7.5 billion = 6.02×10^21 J
= 10 times current world (5.67×10^20 joules), byebye climate.....

USA like consumption:
290 GJ * 7.5 billion = 2.18×10^21 J
NOTE: this is almost 4 times that of the current world (5.67×10^20 joules)

Japan/EU like consumption:
150 GJ * 7.5 billion = 1.13×10^21 J
Still twice that of the current world (5.67×10^20 joules)

'Good'? scenario? (Hong Kong like)
81 GJ * 7.5 billion = 6.08×10^20 J
Close to the current world (5.67×10^20 joules)

Future energy consumption estimates with 11 billion predators humans
Worst possible scenario:
If all the 11 billion people would consume as much energy as Qatar/capita (
803 GJ * 11 billion = 8.83×10^21 J
= 15+ times current world (5.67×10^20 joules), byebye climate.....

USA like consumption:
290 GJ * 11 billion = 3.19×10^21 J
= 5.6 times current world (5.67×10^20 joules)

Japan/EU like consumption:
150 GJ * 11 billion = 1.65×10^21 J
= 2.9 times current world (5.67×10^20 joules)

Good? scenario? (Hong Kong like)
81 GJ * 11 billion = 8.91×10^20 J
= 1.5 times current world (5.67×10^20 joules)

How many windmill, solar panels or nuclear reactors would we need to supply that energy (assuming no coal/oil world)?

Solar:
a 1 m^2 solar panel receives 1000Wp of solar irradiance. It converts 15-25% of that to usable energy. For the sake of argument lets assume very efficient panels (25%). That would mean 250Wp per m^2 . With conversion factor of 1.0 for Wp to kWh/a (this is better than you get in the most of Europe, I think in Netherlands you get about 0.8-0.85 depending on many factors). Since it is more about the order of magnitudes, this should not really effect the final answers.

So a 1m^2 250Wp solar panel gives 250kWh per year (= ~ 900MJ)

The world would need for 11 billion people:
'Good' scenario
9×10^20 J / 9×10^8 J =1×10^12 m2 of solar panels (1 million km2)
We would have to cover an area the size of Egypt!
https://en.wikipedia.org/wiki/Egypt

'Merica like scenario:
32×10^20 J / 9×10^8 J =3.5×10^12 m2 of solar panels
That is an area larger than India, or about 1/3 of the USA (or Canada or China)

Bad scenario:
9×10^21 J / 9×10^8 J =1×10^13 m2 of solar panels
10 million km2!!)
This is an area larger than the USA! (or Canada or China for that matter)

So clearly solar panels would need a lot of room.................

Wind:
A big land-based wind-turbine is usually a couple of MW (rated capacity). With rotor diameter of less than 100 meter. Super big wind-turbines installed on sea can be 10MW and have rotor diameters of up to 150 meter. This is with the current tech of course, they could become better/bigger in the future.
The biggest (land) wind-turbine in my country (Netherlands) is a 4.5MW build in the Eemshaven, with axis height of 132 meters (rotor diameter of 136 meter). The wingtip will reach 200 meter heigh. It costs about 4.5 million Euro to build.
A wind-turbine can achieve a conversion factor of 25-30% over a year.

Lets for our calculations take a 5MW (rated windturbine) * 24 * 365.25 * 0.3 (factor) = 13,150 MWh/year (47,340 GJ). I'm going to take some liberty here and round it up to 50 TJ (5×10^13 J)

Real world example:
The Gemini Wind Farm in the North Sea will span an area 68 km2 with an estimated output of 2.5TWh per year (9 PJ , 9×10^15 J)
https://web.archive.org/web/20120614...?key=152g8fffa

The world would need for 11 billion people:
'Good' scenario
9×10^20 J / 5×10^13 J = 18 million big (5MW) windmillsturbines
100,000 x 68 km2 = 6.8 million km2

'Merica like scenario:
32×10^20 J / 5×10^13 J = 64 million windturbines
24 million km2, Area ofUSA+Canada+a little more

Bad scenario:
9×10^21 J / 5×10^13 J =180 million wind-ies
68 million km2
In comparison: Total landmass of earth is 149 million km2. Including the sea 510 million km2

Nuclear
Lets go nuclear then ?

The ~400 operational nuclear power plants produce about 2,500TWh (9,000 PJ , 9×10^18 J)
https://www.iaea.org/PRIS/WorldStati...roduction.aspx

= (~1.6×10^14 J)
http://www.world-nuclear.org/informa...-overview.aspx

'Good' scenario
9×10^20 J / 9×10^18 J = 100 x the current amount of plants (400)
consuming 5,625,000 tonnes of natural uranium

Bad scenario:
9×10^21 J / 9×10^18 J = 1000 x the current amount of plants (400)
consuming 56,250,000 tonnes of natural uranium

I hope I made a lot of mistakes, cause it ain't looking good.......
Unlikely to solve the problem by having made mistakes, the correction of which would uniformly be in our favor.
Your results come to the same conclusion as the free online book by a UK physicist, Sustainable Energy Without the Hot Air, where he sets numbers to many things and concludes nation sized energy appetites require nation-sized renewable energy deployments.

https://withouthotair.com/
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Old 2019-12-22, 10:54   #27
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Humans remain a problem as long as the average person chooses opinions over logic, entertainment over practice, gluttony over frugality, etc.

Last fiddled with by Blackadder on 2019-12-22 at 10:55
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