Abstract
IQ loss, Solar power, and misconceptions
and an egg?!?
"Ladies and gentlemen of the class of 2012, wear sunscreen... "
Well, again it's been quite a while since last I wrote something. Mostly the reason is I was in Louisville KY visiting my daughter's great-grandma which is incidentally indeed great, and I enjoy calling her "Savta" (which is Hebrew for grandma and implies her actually being MY grandma), partly because the position was unmanned, i.e. I have no grandparents of my own, but also partly due to said greatness...
During that visit the internet connection was tenuous at best, and so I wasted away my time (and energy and brains) by zombiing-out in front of a relatively old computer game - Elder-scrolls IV: Oblivion, which is basically a fantasy game that does exactly that - throws your real life into oblivion.
The main straightforward result of this is ,basically now I am in search of an additional ~40-50 IQ points to compensate for my lost mind (I seem to recall a song about that... hmmm....).
Additionally someone told me it must not be as bad as I think and that I'm pretty smart as it is. enter this vain attempt at a blog as a failing effort to prove myself wrong and them right :)
So anyway, one of the courses I'm supposed to be taking this semester is a course about environmental physics, which for this course is really a misnomer. it should have been called plain "Mental Physics" since the person giving the lectures is a bit of a cognitive dissonance. the guy has credentials as long as the great wall of china, and obviously the guy's bright as all hell, but he has some kind of an issue that prevents him from writing anything on the whiteboard, so the whole course is conducted without writing down a single physical formula.
I don't mean to be disrespectful, mind you, I'm just ranting a bit about the fact that I'm having difficulty following his train of thought. oh by the way, at this point in time another student and myself comprise the totality of the survivor list, that started some 15-strong.
Anyway, so in an effort to basically teach myself the whole (nonexistent) syllabus I am writing this post that will have to do with environmental physics and ultimately some of the lies people tell you about green-energy.
How much energy does it take to live anyway?
Well, the above subtitle or subsection or dissection or C-section or whatever, is actually the first and foremost question we have to answer upon entering this game of energy production vs. consumption, which is really what's it all about anyway, right?
by the way, I am going to be EXTREMELY optimistic this whole analysis just to underscore the seriousness of the situation we're in and the blatancy of the lies all of us are being told...
So let's approach this question by breaking it down to small bits:
1. how much energy is spent by simply surviving? (on average! on average! sheesh... don't kill me YET)
2. how much energy is spent on living i.e. driving to work and back, computers, home appliances etc..
So in order to answer the first question, let's take the average age across the world's population, find out what the average calorie intake at that age and that will be our rule of thumb, assuming basically what goes in goes out in terms of energy.
So for some cold hard data:
- Median age of the population is 28.4 years overall, and since roughly 70% of the people in the world age anywhere between 14 to 65 we can't be too off the mark by saying the average age is probably somewhere between 23-33 years.
- Now the average male weight around the world ranges from 65-87 kg.
- the same for women ranges 56-75 kg.
Now as I said before I'm going to be EXTREMELY optimistic so I'll take the lower entries, make the assumption that women and men distribute roughly 50-50 of the worlds population.
The calorie intake of an average man at 65kg, no physical exercise, at age 23 where metabolism hadn't yet gone too far down, comes out about 1550 Kcal/day.
For women it turns out to be about 1350 Kcal/day.
Now if you happen to be a large person, reading this, DON'T BE ALARMED, again, I am optimistic to a fault here, and I couldn't survive on 1500 Kcal/day even if I wanted to...
Well, let's average this out to about 1450 Kcal/day and find out that:
\[1 cal \approx 4.1 J\\ 1450 Kcal = 1450\times 10^3\times4.1\\ P= 5945000 \text{ Joul per day} \Rightarrow P_{\text{average person}}\approx 70 W
\]
Ok, so this answers part 1 of our question but what about part 2? well this could get messy now, cause navigating the sea of data on average gas consumption, power consumption per capita etc. is all but impossible,so I'll do what most physicists do, either ignore the problem or invent some lame excuse why it's insignificant...
for myself I think the honest thing to do here is say that I just don't know, and am to lazy to calculate it right now so let's just go with surviving for now...
So indeed the good news is that if we were all blown back into the stone-age, lived life simple and basic, human population will never exceed the ability of the sun to supply energy, mainly in the form of food and warmth...
if we choose to be egomaniacs (as a race, which we probably are), and annihilate every other non-beneficial life form on this planet, and limit ourselves to living off sugarcane (8% efficiency), wheat, and stuff like that we could very well multiply earth's population by a couple orders of magnitude and still be OK.
but wait a minute! that doesn't get me where I intended to go, so again like every physicist does every once in a while... remember that pesky thing I was too lazy to evaluate? namely the energy cost of living (as opposed to survival)? well the data doesn't support the intended conclusion so let's get different data!!!
I'm largely joking around, but I shit you not, this sort of thing happens all the time in hard science, and don't even get me started on "soft science" as they call it (no offense but really to me these are better named "non-science", and I might write a post about that at some point when I feel sufficiently antagonistic).
Anyway, so I looked around and found an amazing piece of information. it turns out that the average energy consumption per capita in the world, in 2008 was 21,228kWh, that is, after quick unit conversion:
\[E_{year}=21,228\cdot 10^3 \frac{J}{sec} \cdot hour= 21,228\cdot 10^3\cdot 60\cdot 60\\
\Rightarrow P_{\text{average, 2008}}= \frac{21,228\cdot 10^3}{365\cdot 24}\approx 2400=2.4kW \]
Which is dire news indeed, since the total available solar energy on the planet was about \(10^{18}\,W\) ,
and now the total consumption of the human race turns out to be around \(1.6\cdot 10^{13} W\).
or in other words, each person, on average needs 2 square meters of land to his name in order to sustain a mostly modern way of life.
And again, after checking my math, again and again, I am shocked with the fact that presumably if the United States so wished it could have easily supplied the whole world with enough power 5 times over, by simply transforming Arizona into a huge mirror-field!! this is how:
\[A_{AZ}\approx 3\cdot 10^{11}m^2\\
\frac{A_{AZ}}{(2m^2)\cdot(Population)}\approx \frac{3\cdot 10^{11}}{15\cdot 10^9}=20\]
Enter the current efficiency of Solar power plants at about 44% cutting edge, but let's be cynical and take what's out there on the market right now at about 25% efficiency and still we get that the US could have easily supplied the world with it's power needs about 5 times over.
Damn it! did I just convert -myself- to the dark side?.... ummm light side? err.. sunny-side-up? whatever... I think I might join solar research.
\]
Ok, so this answers part 1 of our question but what about part 2? well this could get messy now, cause navigating the sea of data on average gas consumption, power consumption per capita etc. is all but impossible,so I'll do what most physicists do, either ignore the problem or invent some lame excuse why it's insignificant...
for myself I think the honest thing to do here is say that I just don't know, and am to lazy to calculate it right now so let's just go with surviving for now...
Solar energy - not quite what it's cracked up to be
One not so sunny day at my campus, a clean energy activist came up to me and asked if I could sign a petition to support green energy, mainly raising 2-3 more solar farms in our sun-scorched state, and erecting wind-turbine fields in the Negev etc.
I said I was willing to sign it, but first I would like to hear some facts and data about the cost-effectiveness of such endeavor, and if he could please tell me what are some of the adverse affects, and what is intended by way of offsetting those.
I don't quite remember if I ended up signing it or not, but that's beside the point. the point being we rarely, if ever, get educated about the downside of so called green energy, and for the most part most of us buy into the idea of traceless energy production hook, line and sinker.
In a previous post I mentioned the amount of solar radiation the earth's surface experiences, is given by \(S_{\oplus}\approx1360\, \frac{J}{sec\cdot m^2} \).
so the good news are there's enough solar energy to go around for all of us to survive, as one might suspect... after all indirectly that's what's happening anyway...
But here's the shocker:
\[\text{Earth's surface} \equiv A_{\oplus}=4\pi r_{\oplus}^2 = 4\pi \times 6400,000^2\approx 5\cdot 10^{14}\, m^2 \\
\text{Total solar energy on earth, per second} \equiv E_{\oplus}=A_{\oplus}\times S_{\oplus}\approx 7\cdot 10^{17} W\\
\text{Total Energy used (surviving mode)}=E_{humen\, race}=7\cdot 10^9\cdot 70 \approx 5\cdot 10^{11} W \]
and even if we only use Earth's available land, forget about covering the sea with mirrors we get about \( 0.29 \times E_{\oplus}\approx 2 \cdot10^{17} W \) .
so the good news are there's enough solar energy to go around for all of us to survive, as one might suspect... after all indirectly that's what's happening anyway...
But here's the shocker:
\[\text{Earth's surface} \equiv A_{\oplus}=4\pi r_{\oplus}^2 = 4\pi \times 6400,000^2\approx 5\cdot 10^{14}\, m^2 \\
\text{Total solar energy on earth, per second} \equiv E_{\oplus}=A_{\oplus}\times S_{\oplus}\approx 7\cdot 10^{17} W\\
\text{Total Energy used (surviving mode)}=E_{humen\, race}=7\cdot 10^9\cdot 70 \approx 5\cdot 10^{11} W \]
and even if we only use Earth's available land, forget about covering the sea with mirrors we get about \( 0.29 \times E_{\oplus}\approx 2 \cdot10^{17} W \) .
So indeed the good news is that if we were all blown back into the stone-age, lived life simple and basic, human population will never exceed the ability of the sun to supply energy, mainly in the form of food and warmth...
if we choose to be egomaniacs (as a race, which we probably are), and annihilate every other non-beneficial life form on this planet, and limit ourselves to living off sugarcane (8% efficiency), wheat, and stuff like that we could very well multiply earth's population by a couple orders of magnitude and still be OK.
but wait a minute! that doesn't get me where I intended to go, so again like every physicist does every once in a while... remember that pesky thing I was too lazy to evaluate? namely the energy cost of living (as opposed to survival)? well the data doesn't support the intended conclusion so let's get different data!!!
I'm largely joking around, but I shit you not, this sort of thing happens all the time in hard science, and don't even get me started on "soft science" as they call it (no offense but really to me these are better named "non-science", and I might write a post about that at some point when I feel sufficiently antagonistic).
Anyway, so I looked around and found an amazing piece of information. it turns out that the average energy consumption per capita in the world, in 2008 was 21,228kWh, that is, after quick unit conversion:
\[E_{year}=21,228\cdot 10^3 \frac{J}{sec} \cdot hour= 21,228\cdot 10^3\cdot 60\cdot 60\\
\Rightarrow P_{\text{average, 2008}}= \frac{21,228\cdot 10^3}{365\cdot 24}\approx 2400=2.4kW \]
Which is dire news indeed, since the total available solar energy on the planet was about \(10^{18}\,W\) ,
and now the total consumption of the human race turns out to be around \(1.6\cdot 10^{13} W\).
or in other words, each person, on average needs 2 square meters of land to his name in order to sustain a mostly modern way of life.
And again, after checking my math, again and again, I am shocked with the fact that presumably if the United States so wished it could have easily supplied the whole world with enough power 5 times over, by simply transforming Arizona into a huge mirror-field!! this is how:
\[A_{AZ}\approx 3\cdot 10^{11}m^2\\
\frac{A_{AZ}}{(2m^2)\cdot(Population)}\approx \frac{3\cdot 10^{11}}{15\cdot 10^9}=20\]
Enter the current efficiency of Solar power plants at about 44% cutting edge, but let's be cynical and take what's out there on the market right now at about 25% efficiency and still we get that the US could have easily supplied the world with it's power needs about 5 times over.
Damn it! did I just convert -myself- to the dark side?.... ummm light side? err.. sunny-side-up? whatever... I think I might join solar research.
|
|
Wow, hold yer horses boys, and let's get \(\mathcal{R}\)eal. it seems that we have some more calculation to make.
First off, the earth's solar constant, as it happens, relates to the solar radiation the earth experiences as a black body meaning that up in the upper atmosphere, beyond the clouds and ozone, when facing the sun directly we get \(1360\,\frac{W}{m^2}\). So we have to average it over night and day, plus we took the whole surface of the earth when really, we should have taken incident area meaning:
\[A_I=\text{Incident area}=\pi r_\oplus^2\]
So, we have to take what we got and divide it by 4, average it over a cosine squared function (dividing it in 2 again), AND to top it all off we have to account for cloud cover, so let's divide it by another 2. thus we get:
\[E_\oplus\approx 4\cdot 10^{16}\]
Now apparently, when using mirror collectors, we need to cool them down, so the total available area drops down to about a fifth, let's factor in the 25% efficiency factor we talked about earlier and get to about 5% of the available energy, that gets us to
\[E_\oplus\approx 2\cdot 10^{15}\]
Multiply that by the percentage of available land i.e. 29% to get:
\[E_\oplus\approx 6\cdot 10^{14}\]
So we get to the conclusion that we need about \(\frac{1}{40}\) of our land in order to account for the global power demand. Mind you, that all of these calculation were done disregarding prevalent trends, meaning the average person in the US uses about 5.5 times the average power consumption, and the current trend is towards that way of life. so with significant technological progress things are bound to get worse in that respect.
As it is forget about using Arizona as a giant solar farm, try Greenland and India combined.
And I didn't even get started! I mean, try factoring in dust!
as it so happens, the mirrors need to be constantly cleaned, as dust quickly builds up, and when it does, efficiency goes WAY down - try 1% percent efficiency instead of 20%.
You know what? I promised to be optimistic though,so let's take cutting edge solar technology at about 44% efficiency, meaning we narrowed it down from India and Greenland to oh, let's say JUST Greenland. Let's just say I doubt the good people of Greenland are that accommodating, and I don't think you'll get a better response from the people of India.
Of course that's a fallacy right there, as it is not required for all collectors to be at the same place but in terms of land per capita it means that each person has to own about 267 square meters, which is quite a lot, it's actually about 50'X50' area.
So unless we act and make Lennon's vision of no countries real, it's a bit of a toughie.
Hey - what was that about traceless energy production?
All we've done as of now is just talk physics, but what about environmental impact?
The common (mis)conception is that solar energy, being renewable (which it is) also has little to no impact on the environment.
that's only partly true, what's true is there's no airborne pollution, no solid waste, trash etc. BUT what's there is oh, I don't know, thermal pollution? light pollution? displacement of wild-life, and the possible destruction of unique species. and that's just off the top of my head and remember I'm NOT an environment scientist/wild-life expert/forester or any other kind of nature geek.
Now I'm all for green and clean energy, and it's a noble calling to further develop solar energy production, hey, I might even go into solar energy research myself.
YES IT'S THAT IMPORTANT (that I might actually dedicate my life to this).
but, do not ever fall for something that sounds too good to be true, it usually just ain't.
and green energy,if not carefully and thoughtfully developed might be almost or as bad as
conventional energy.
Again I'm no expert in ecology, so take what I say with a grain of salt as far as natural ramifications, but trust me, on the sunscreen... err physics.
Next time: Wind energy or Wormholes
