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MindMover

(5,016 posts)
65. Finally talking some sense about climate change....but then you digress
Mon Aug 12, 2013, 08:08 PM
Aug 2013

to making a patently false statement about retrievable energy in sun and wind....

"If you took the amount of sunlight that hits the Earth in one second and converted it into matter, how much would it weigh? How much energy is this in practical terms?
This is an excellent question, which puts the energy balance on Earth into perspective. Let me answer this question in two steps, and then let me compare the amount of energy from the Sun to the amount humankind is using right now.

The energy per time put out by the Sun is its luminosity, 3.8 x 1026 Joules per second (or Watts). Using Einstein's renowned formula that describes how much mass is transformed into energy, when energy is being produced, E = M * c2 (or: Energy = Mass * (Speed of Light)2), as 1 Joule = 1 kg m2/s2 and c = 300,000,000 m/s, the mass the Sun burns into energy every second is:


Mass/Time = 3.8 x 1026/(3 x 108)2 kg/s = 4.4 x 109 kg/s

or roughly 4 million tons per second.
At its distance of 1 Astronomical Unit (150 million km), the Earth is hit by the Sun's energy flux F = 1400 Joules/s/m2. We call this quantity the "solar constant", as this value averaged over each year is constant within better than 1% over time. With an Earth radius of approx 6400 km, the area, which is (pi * Earth's radius)2, with which the Earth intercepts sunlight is (pi * Earth's radius)2 = 1.3 x 1014 m2 making the amount of energy captured by the Earth each second:


F * (pi * Earth's radius)2 = 1.8 x 1017 Joules/s
According to the same procedure as above this makes the mass to produce this amount of energy per second:


Mass captured as sunlight per second = 1.8 x 1017 / (3 x 108)2 kg/s = 2 kg/s

This is about 4.5 lbs/s or close to 5 lbs/s.

To put these numbers into a perspective with highly practical relevance, on average, humankind is only using about 1/10,000 of that amount for its total energy consumption. In other words, sunlight seems to be a viable option for our energy needs, at least from the perspective of the total amount needed. Or from the point of view of mass, we are transforming about 20 kg of mass per day into energy for our energy consumption.

If we were to use much more energy, say a sizeable fraction of the amount that the Earth gets from the Sun, the Earth would have to heat up considerably in order to get rid of the waste heat. Every power plant needs a cooler to get rid of its heat; the Earth as a whole can only do this by getting hotter."

Dr. Eberhard Moebius
(January 2005)

The situation seem s all but hopeless Generic Other Aug 2013 #1
Ah, so you're an apologist for coal/gas/fracking. wtmusic Aug 2013 #2
Renewables have had nowhere near the financial support / subsidies that coal/gas/fracking have... Flaxbee Aug 2013 #3
That excuse has been around for forty years wtmusic Aug 2013 #4
You are correct with current technologies about renewables ... however MindMover Aug 2013 #13
Right now, can they do the job? NutmegYankee Aug 2013 #14
Yes current renewable technology CAN do the job. kristopher Aug 2013 #21
OK. Just what are you declaring independence from? wtmusic Aug 2013 #25
From being sucked dry by the leeches and vampires known as ... MindMover Aug 2013 #47
You do understand the difference between energy companies wtmusic Aug 2013 #48
Yes, and you will now state that utilities have nothing to do with MindMover Aug 2013 #49
Utilties are permitted to charge 10% more than their costs. wtmusic Aug 2013 #50
Expanding the rate base drives unneeded generation and wasteful spending on facilities kristopher Aug 2013 #52
Been there done that and very proud to say it ... in Northern California MindMover Aug 2013 #53
For how long, 6 hours? wtmusic Aug 2013 #54
Wow, you really are a nonbeliever.... MindMover Aug 2013 #55
Let's put it this way wtmusic Aug 2013 #56
Coming to a town and city near you .... Soon MindMover Aug 2013 #57
That's the Church of Renewables mantra: "coming soon". wtmusic Aug 2013 #58
Not really that big a deal since it is currently known technology applied MindMover Aug 2013 #59
There is not even close to enough retrievable energy in sun/wind to meet 21st century needs. wtmusic Aug 2013 #61
Finally talking some sense about climate change....but then you digress MindMover Aug 2013 #65
Don't you recognize the strategy of accusing others of your own weakness when you see it? kristopher Aug 2013 #51
One minor point. Stonepounder Aug 2013 #16
The leftovers of coal kill about 15,000 Americans every year wtmusic Aug 2013 #24
So, all the stuff that is flowing into the ocean from Fukishima is just a Coke can's worth? n/t Stonepounder Aug 2013 #27
Hype that keeps the public buying newspapers. wtmusic Aug 2013 #29
Much less in fact. FBaggins Aug 2013 #33
In your zeal to promote nuclear you simply refuse to be bound by the truth kristopher Aug 2013 #19
My Norwegian neighbor carla Aug 2013 #5
I hope he doesn't have anything in that fridge/freezer that can spoil wtmusic Aug 2013 #6
You may have noticed that your landline phone doesn't go out when we lose power. That's because jtuck004 Aug 2013 #17
A refrigerator uses 120x the energy of a landline phone wtmusic Aug 2013 #18
You can define parameters so they suit your outcome, which doesn't add anything but more weasel jtuck004 Aug 2013 #26
"Greedy and clasping hands"? That's a laugh. wtmusic Aug 2013 #28
Enron. n/t jtuck004 Aug 2013 #30
Not only was Enron not a utility wtmusic Aug 2013 #36
You want to have it both ways. Not hardly worth talking to at this point. jtuck004 Aug 2013 #38
I have no earthly idea what you want wtmusic Aug 2013 #39
If you're really concerned about that you can get a tank of LP, and a dual fuel fridge AtheistCrusader Aug 2013 #34
Solar in Norway? Helen Borg Aug 2013 #44
You're right. kristopher Aug 2013 #20
Not on nuke power Generic Other Aug 2013 #7
Wind/solar = renewables, and Hanford didn't have anything to do with power generation, did it? wtmusic Aug 2013 #9
Hanford does have one commercial reactor these days Generic Other Aug 2013 #10
So they do, I didn't know that. wtmusic Aug 2013 #11
My city burns garbage in an incinerator Generic Other Aug 2013 #15
The problem is not a shortage of clean energy at all wtmusic Aug 2013 #22
But you are never going to convince most of us that this is true Generic Other Aug 2013 #31
I'm fortunate in that I've actually been able to change quite a few minds wtmusic Aug 2013 #37
There are no logical arguments for using nuclear technology Generic Other Aug 2013 #60
Then you are for coal/gas/fracking. You support climate change. wtmusic Aug 2013 #63
That's ridiculous Generic Other Aug 2013 #64
Burning garbage creates the most deadly waste of all NickB79 Aug 2013 #43
The industry does say they burn clean and gov. regs are strict Generic Other Aug 2013 #62
Columbia Generating Station cranks out 10% of the state's power. AtheistCrusader Aug 2013 #35
I have been cutting energy use my whole life Generic Other Aug 2013 #66
Tidal power is loathsome. hunter Aug 2013 #68
I read that there are only 20 viable sites in the world for tidal? Generic Other Aug 2013 #69
I have many stories about the old days of the anti-nuclear movement... hunter Aug 2013 #71
Global energy consumption: Nuclear 2.7%; Renewables 16.7% kristopher Aug 2013 #23
Encouraging news Generic Other Aug 2013 #32
and this surprises them why? hollysmom Aug 2013 #8
I don't get why they would be surprised sakabatou Aug 2013 #12
It doesn't surprise them Generic Other Aug 2013 #67
This may not fly, but here goes. ConcernedCanuk Aug 2013 #40
Yeah but we won in 2013. wtmusic Aug 2013 #41
Only took ya 300 years! ConcernedCanuk Aug 2013 #42
We obviously need to go to war over this. L0oniX Aug 2013 #45
again? ConcernedCanuk Aug 2013 #46
Notice they never mention what else they find. Octafish Aug 2013 #70
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