Wind and Solar vs Coal, Gasoline, Nuclear

Easier to see chart of predicted energy by source for the different Shared Socio-Economic Pathways that the scientists are now using for the updated climate change models. Is there really that much recoverable oil left? 120 million barrels a day for the next 80 years and beyond? We are already fracking the source rock and drilling in the deep ocean. After this there is nothing left.
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They are more optimistic than the UN (predicts 10.5 billion peak) on controlling the peak population. Our current debt/ growth/ inequality based economic system requires constant 3% growth of GPD in order to create "jobs" for full employment. This results in a doubling of GDP every 25 years and would result in nearly the level which is shown in SSP5. Is it really possible to see the size of the human endeavor as 8 times bigger than today in 75 years given the constraints of raw material throughput and declining resource grades?
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https://www.carbonbrief.org/explainer-how-shared-socioeconomic-pathways-explore-future-climate-change?fbclid=IwAR3-CPW2sRe0Ov6HSW5IHgRrEWy0Gb1Vex4LtUR3e6mGSlCGuCzMyA2UygQ
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space privateers coming online with an eye towards mining asteroids & other planetary bodies i've previously suggested an alternative.
worst case there's always the dyson sphere.

but for some reason in almost 200 pages there's zero acknowledgement of full-time uninterrupted orbital solar power which completely torpedoes the renewable naysayers main gripe of low duty factor.
last i heard in an interview with an engineer working on this he claimed money was the only hurdle & that the chinese government backing him had green lit the project.
that wuz just before the 2008 world financial collapse so i'm guessing that shelved it but haven't heard anything since so don't really know for sure.
 
"Various SBSP proposals have been researched since the early 1970s,[1][2] but none are economically viable with present-day space launch infrastructure. Some technologists speculate that this may change in the distant future if an off-world industrial base were to be developed that could manufacture solar power satellites out of asteroids or lunar material, or if radical new space launch technologies other than rocketry should become available in the future.

Besides the cost of implementing such a system, SBSP also introduces several technological hurdles, including the problem of transmitting energy from orbit to Earth's surface for use. Since wires extending from Earth's surface to an orbiting satellite are neither practical nor feasible with current technology, SBSP designs generally include the use of some manner of wireless power transmission with its concomitant conversion inefficiencies, as well as land use concerns for the necessary antenna stations to receive the energy at Earth's surface. The collecting satellite would convert solar energy into electrical energy on board, powering a microwave transmitter or laser emitter, and transmit this energy to a collector (or microwave rectenna) on Earth's surface. Contrary to appearances of SBSP in popular novels and video games, most designs propose beam energy densities that are not harmful if human beings were to be inadvertently exposed, such as if a transmitting satellite's beam were to wander off-course. But the vast size of the receiving antennas that would be necessary would still require large blocks of land near the end users to be procured and dedicated to this purpose. The service life of space-based collectors in the face of challenges from long-term exposure to the space environment, including degradation from radiation and micrometeoroid damage, could also become a concern for SBSP."
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https://en.wikipedia.org/wiki/Space-based_solar_power
 
sendler2112 said:
80 years and beyond? We are already fracking the source rock and drilling in the deep ocean. After this there is nothing left.
There will always be some left. It will just be so expensive that it won't be worth extracting it. And that will happen gradually, not all at once.

100 years from now, if we are lucky, most of our energy will come from non-fossil-fuel sources, and the remaining oil will be used as feedstock for the various industrial processes that need them.
 
billvon said:
100 years from now, if we are lucky, most of our energy will come from non-fossil-fuel sources, and the remaining oil will be used as feedstock for the various industrial processes that need them.
It just strikes me as improbable (delusional) the way that all of these SSP predictions that will now be used as the forcing scenarios (except SSP1 which implies some proactive social adaptation and world cooperation) show oil consumption increasing to 100+ million barrels/ day and staying there through the end of the century and off the end of the timeline with no reduction in sight.
 
sendler2112 said:
It just strikes me as improbable (delusional) the way that all of these SSP predictions that will now be used as the forcing scenarios (except SSP1 which implies some proactive social adaptation and world cooperation) show oil consumption increasing to 100+ million barrels/ day and staying there through the end of the century and off the end of the timeline with no reduction in sight.
Well, oil usage is going to be reduced one way or another. Our best outcomes will occur if that's at a time of our choosing.
 
Punx0r said:
As it currently stands orbital solar isn't feasible but it could be in ~20 years.

20 is still better than 80 to 100.
there always been a lot of optimistic claims made when it comes to renewables because they're largely fueled by snake oil.
but push come to shove back to the wall orbital solar would get figured out right quick overlooking a few fried raptors no worries.
 
Toorbough ULL-Zeveigh said:
20 is still better than 80 to 100.
there always been a lot of optimistic claims made when it comes to renewables because they're largely fueled by snake oil.
but push come to shove back to the wall orbital solar would get figured out right quick overlooking a few fried raptors no worries.

What about the slight question marks of lifting all of that mass into orbit? World solar averaged 52 GW production last year. We would need 100 times the current world build out. In orbit. Just for the panels. To make it to the 8 TW that it will take to supply all energy. With a simultaneous complete conversion of all built out machines, processes, buildings, to electric. And then there is the issue of sending and receiving 8 TW wirelessly from orbit.
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"For example, the 1978 NASA study of solar power satellites required a 1-kilometre-diameter (0.62 mi) transmitting antenna and a 10-kilometre-diameter (6.2 mi) receiving rectenna for a microwave beam at 2.45 GHz.[71] These sizes can be somewhat decreased by using shorter wavelengths, although short wavelengths may have difficulties with atmospheric absorption and beam blockage by rain or water droplets. Because of the "thinned-array curse", it is not possible to make a narrower beam by combining the beams of several smaller satellites."
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"a large-area 10 km diameter receiving array allows large total power levels to be used while operating at the low power density suggested for human electromagnetic exposure safety. A human safe power density of 1 mW/cm2 distributed across a 10 km diameter area corresponds to 750 megawatts total power level. This is the power level found in many modern electric power plants. For comparison, a solar PV farm of similar size might easily exceed 10,000 megawatts (rounded) at best conditions during daytime."
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https://en.wikipedia.org/wiki/Wireless_power_transfer#Microwaves
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10,000 1km antennas in orbit. And 10,000 10km rectennas on the ground. For 8 TW average. Less than half of what we are using now which might suffice with a perfect electrification of everything.
 
How Tesla's SolarCity factory in Buffalo is affecting the community
[youtube]Bx0bBTyRIKo[/youtube]
^CNBC discusses Tesla and the Vanity Fair article.
https://www.vanityfair.com/news/2019/08/how-elon-musk-gambled-tesla-to-save-solarcity
 
sendler2112 said:
using shorter wavelengths, although short wavelengths may have difficulties with atmospheric absorption and beam blockage by rain or water droplets.
going from memory (forgot the engineers name who was working with the chinese gov so can't search for it effectively) but he proposed wide area, distributed low amplitude infrared laser transmission with receiving stations located in desert areas to minimize scattering, but as you know IR also penetrates cloud cover better.
spread over a square mile iirc his calculation wuz it would raise the surface temp of anything passing thru the beam by a fraction of a degreeC, "like having your skin kissed by the sun on a warm day".
or so he sez; proof is in the eating.

What about the slight question marks of lifting all of that mass into orbit?
on this point i'll offer my own wag speculation as to what i think the real reason the project was axed & progress is being stalled generally .
most people on this sphere & elsewhere are blissfully unaware that the era of Si based semi's is over
& done for, having gone as far as it can go (a 'sea-change').
it's a walking dead, just as what the EV is doing to ICE right now, only hanging on until the guys with all the money (the 'beancounters' ) can divest themselves of the old tech.
when the new tech comes online, obviously it will make a lot of the components smaller, lighter, more efficient & should be cheaper (tho not necessarily at first).
who knows what the characteristics of a Ge (or whatever) based PV system will look like but for certain it can only be overall better.

it makes (some) sense why there's no appetite to invest heavily in orbital solar now, a wait & see what develops attitude.
if we really needed to tho i think it can & will be quickly dusted off the shelf with all the attendent problems attacked manhatten project style.
there's nothing insurmountable here is my point, no breakthrough required.
this is why the gloom & doom chicken-littles out there prognosticating we're headed back to horse & buggy or the stone age have no concept of the vast amount of existing hi-tech sitting on corporate shelves.
 
Toorbough ULL-Zeveigh said:
there's nothing insurmountable here is my point, no breakthrough required.
this is why the gloom & doom chicken-littles out there prognosticating we're headed back to horse & buggy or the stone age have no concept of the vast amount of existing hi-tech sitting on corporate shelves.
What is the area density of the power tranceiving you are quoting? Show me the math. Microwaves require 10km diameter, which is 78 square km, for 750 MW. Might just as well pick out a sunny spot that big on Earth and fill it with panels for a small fraction of the price and get many times more capacity right here.
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That is the problem with most of these Star Trek future solutions. They sound really cool. And might make for a fun toy to have a few dozen 1 MW stations to play with. But when you understand scale and do the math, you will see how impractical they are on lift mass and hardware area even if they are not technically impossible.
 
sendler2112 said:
What is the area density of the power tranceiving you are quoting? Show me the math. Microwaves require 10km diameter, which is 78 square km, for 750 MW. Might just as well pick out a sunny spot that big on Earth and fill it with panels for a small fraction of the price and get many times more capacity right here.
That would work for daytime power. For the lower energy requirements at night, beamed power may play a role.

Existing designs come in at about 20 kilograms/kw. It is likely that can be brought to 5kg/kw. Satellite costs themselves will run about $2/watt. That's $10B launch cost and $2 billion for a 1GW solar plant, launched on Falcon Heavys. If Starship meets its price targets, that's $250 million in launch costs, so total just over $2 billion. Compare that to $9 billion for a new 2-4GW nuclear plant.
 
sendler2112 said:
Can orbital lasers illuminate standard solar farm's panels safely?
An excellent, and difficult to answer, question.

Per OSHA standards, a laser that results in 1000 watts per square meter over a large area is far, far beyond the safety threshold for any open-air laser intended for use where people might look into the beam (i.e. class 1-3.) But that's the same intensity as the sun, and we have a few million years of experience managing to not go blind by looking at it. It leads to the odd result that an orbital parabolic mirror to focus sunlight on the array would probably pass safety testing but the same intensity laser would not.

One of the pluses of using a laser is that you can perfectly match the wavelength to the receiving PV's bandgap. Silicon PV cells have a bandgap energy of ~1.11 eV, which corresponds to a wavelength of about 1100nm (near IR.) That would result in a receive efficiency of close to 70% with "standard" PV. That's a problem for eye safety, because that wavelength still focuses on your retina but doesn't cause the blink reflex (which protects your eyes from a source like the sun.) You could get around that by using 800nm lasers (red light) which would still cause a blink reflex but be more efficient than sunlight.

That leads to the possibility of using far lower intensity IR or red light to get the same power out of a receiving PV array - and have it still be useful for daytime usage in regular sun. Could you lower the intensity enough to get enough power out of it to make it useful, while placating the people who think that deadly space lasers will kill them and/or render them sterile from radiation? Doubtful. You'd likely need to have a keep-out area of miles with armed sentries, barbed wire fences etc to "protect" the public from red light, all of which would make the project far more costly.

But in theory it would work well.
 
Australia's governmental review into nuclear power has effectively dismissed large scale nuclear as 4-5 times more expensive than renewables. Small modular reactors are expected to be 50%more costly than large nuclear. Build times are in the 15-20year time frame. I'm sure that for the 10s of billions for just one nuke (and 15yrs) we can come up with something more environmentally friendly. Given that humans are willing to spend trillions blowing each other up or posturing to do so every few years...cost in my mind is never an argument...what price do we want to put on the habiltability our planet.
 
Some considerations for the laser. 1050 nm wavelength is common and would be perfect for the panels to convert. Standard 4mm commercial lasers offer 5 mrad divergence. A low Earth orbit at 500 km would result in a 3km beam width on the ground. Probably have to spec something an order of magnitude better. 3 orders of magnitude better for GEO including atmospheric diffraction. The steering accuracy required just from LEO is stated as 1 mrad. Which results in +- 300 meters accuracy on the ground. Steering for any envisioned GEO location would have to be 2 orders of magnitude better than that and require effective divergence of .001 mrad. It's too heavy to lift millions of 1kW lasers to GEO anyway. Prices are currently more like $10,000/ kg to GEO including transfer hardware and fuel.
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https://www.spacex.com/about/capabilities
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What is the best service life that could be designed? 100,000 hours/ 10 years for the lasers. How long do panels last in space?
 
sendler2112 said:
Some considerations for the laser. 1050 nm wavelength is common and would be perfect for the panels to convert.
Yes, except for the eye safety part. I've seen designs that couple a low-power, easily visible laser (i.e. 600nm) with a higher power IR laser - but there's a lot of testing to be done there.
Standard 4mm commercial lasers offer 5 mrad divergence. A low Earth orbit at 500 km would result in a 3km beam width on the ground. Probably have to spec something an order of magnitude better. 3 orders of magnitude better for GEO including atmospheric diffraction.
Agreed, except an SPS will likely be in an intermediate orbit to reduce launch energy required and focusing requirements. The goal is to keep the satellite in sun 75-80% of the time while allowing a line-of-sight to darkside stations (i.e. station elevation >30 degrees) with a minimal constellation.
What is the best service life that could be designed? 100,000 hours/ 10 years for the lasers. How long do panels last in space?
After ~13 years the ISS panels are at about 78% of original power, with most degradation coming from physical damage due to collisions.
 
Curious droid a well established science community youtuber has a few videos on laser space to earth power generation it's a very interesting topic that's been built upon for decades, if we can improve upon lasers divergence we could have a real contender for none stop power generation.
Even if we can't there's work around for a low earth orbit system we have full coverage from gps systems these days so it's just a matter of numbers keeping a satellite in view at all times.

Sounds easy enough but where in the realm of experimental tech when transferring many gigawatts to ground bases the ultimate goal is a star pattern of large solar array with a distant satellite locked in orbit with earth housing a laser supplying the 24/7 generation for 5 or 6 plants globally collecting the power and distributing to country's via a global hvdc grid ready for step down and supply then solar really could supply the world but the video explains many pitfalls and technological advancements needed to challenge such a task but it's by no means impossible.
 
Looks like microwaves rather than lasers are the preferred option. At least that's what the Chinese and Caltech projects are opting for:

https://www.forbes.com/sites/scottsnowden/2019/03/12/solar-power-stations-in-space-could-supply-the-world-with-limitless-energy/amp/
 
The high performance jet fuel JP-10 is now cheaper to produce renewably from plant waste than the traditonal route from coal tar ($5600 Vs. $7000/tonne)

http://english.cas.cn/newsroom/research_news/201907/t20190708_212728.shtml
 
The recent increases in atmospheric methane turn out to be from U.S. and Canadian shale fracking:

www.nationalgeographic.co.uk/environment-and-conservation/2019/08/fracking-boom-tied-methane-spike-earths-atmosphere/amp
 
A further bullet to the head for the "more CO2 will boost plant growth" argument:

https://advances.sciencemag.org/content/5/8/eaax1396

Climate change is increasing the water vapour pressure deficit in the atmosphere which is outweighing increased CO2 fertilisation and reducing plant growth.
 
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