First! Fusion Net Energy Gain

[Roger Wilco]

Interesting if used to progress humanity towards becoming a spacefaring species.

But on Earth? It just sounds dumb at the moment with energy more easily available from the Earth's molten core. Is anyone working on extracting that and putting it to good use?

Geothermal has massive potential, possibly much more than wind or solar.

We don’t need to get anywhere near the core to tap into it.

 

[igor_kavinski]

fusion is probably better.

Except when they start electrolyzing the fresh water sources to produce hydrogen as fuel for the fusion reactions. That extra oxygen will go into the atmosphere and make us all age faster!

(Don't ask me to back that up with science!)

 

[K1052]

Could also pull so much energy out of the core we cause many other issues. Yeah, it'd take a long time, but fusion is probably better.

I'm not opposed to fusion research at all but for now there is a giant ball of fusion energy in the sky we can access with cost effective technology.

 

[Zorba]

Except when they start electrolyzing the fresh water sources to produce hydrogen as fuel for the fusion reactions. That extra oxygen will go into the atmosphere and make us all age faster!

(Don't ask me to back that up with science!)

It'll make up for all the oxygen we've permanently bonded to hydrogen by burning hydrocarbons.

 

[Zorba]

I'm not opposed to fusion research at all but for now there is a giant ball of fusion energy in the sky we can access with cost effective technology.

Completely agree. In general, though, I think energy production and energy efficiency research is probably some of the best bang for the buck we can get. So I'm all for more research into fusion and solar.

 

[igor_kavinski]

solar.

That's a solved problem, isn't it? Just need to get NASA to opensource the schematics they use for their spacecraft and then mass-produce those. Once land is at least 85% covered with solar panels, the energy crisis will become extinct, almost like the steam engine car.

 

[Paratus]

Could also pull so much energy out of the core we cause many other issues. Yeah, it'd take a long time, but fusion is probably better.

A rough estimate puts the energy down there at around 6x10^30 joules. We use about 6x10^20 joules / year so one years worldwide supply is 1 /10 billionth of that energy.

 

[Paratus]

That's a solved problem, isn't it? Just need to get NASA to opensource the schematics they use for their spacecraft and then mass-produce those. Once land is at least 85% covered with solar panels, the energy crisis will become extinct, almost like the steam engine car.

NASA solar arrays are meant to be lightweight and fold up. Ground based arrays don’t need that extra expense.

Second the earth receives in 1 hour of sun light enough energy to power our entire society for a year. So we only need 0.02-0.04% of the earths surface covered in solar arrays - not 85%.

 

[Ajay]

So, as per usual, I put in my plug for building a bunch of Advanced Nuclear Reactors (aka Gen IV). 200-300 MW range to allow faster builds and thus faster ROI. But, instead, ~100B US are being invested in fusion research projects and one power plant scale system. SMH.

 

[skyking]

NASA solar arrays are meant to be lightweight and fold up. Ground based arrays don’t need that extra expense.

Second the earth receives in 1 hour of sun light enough energy to power our entire society for a year. So we only need 0.02-0.04% of the earths surface covered in solar arrays - not 85%.

I don't bother with that meathead.
Solar PV is at about 23% at best.
It is so inexpensive these days, but I will spend an extra 10K on the house build to go after Solar thermal. I can store our own heat and not add to the grid tie mess any more than needed. The vaccuum tube collectors are closer to 60% efficiency, but $$$.
I sure don't want a big bank of batteries in my home to catch fire.

 

[Ajay]

I don't bother with that meathead.
Solar PV is at about 23% at best.
It is so inexpensive these days, but I will spend an extra 10K on the house build to go after Solar thermal. I can store our own heat and not add to the grid tie mess any more than needed. The vaccuum tube collectors are closer to 60% efficiency, but $$$.
I sure don't want a big bank of batteries in my home to catch fire.

Well, commercial scale collector arrays have a lower cost/m^2 than home systems. Semiconductor based solar cells can be a b*tch when it comes to efficiency at a reasonable cost, but considerable work is being done to improve efficiency and and eliminate the immediate efficiency drop off that occurs when solar cells are exposed to sunlight (which is kind of funny in a way).

 

[Lost_in_the_HTTP]

So, y'all have never seen 'A Crack In The World'?

Crack in the World - Wikipedia

en.wikipedia.org

 

[Zorba]

A rough estimate puts the energy down there at around 6x10^30 joules. We use about 6x10^20 joules / year so one years worldwide supply is 1 /10 billionth of that energy.

But how much do you have to pull out before tectonic plates slow down or we affect the magnetic field?

Crust level geothermal is great, core level makes me a bit nervous we'd fuck something up, because that is what we tend to do.

 

[igor_kavinski]

We are living on a giant onion made of rocky layers. It's a miracle we've made it this far.

 

[Moonbeam]

NASA solar arrays are meant to be lightweight and fold up. Ground based arrays don’t need that extra expense.

Second the earth receives in 1 hour of sun light enough energy to power our entire society for a year. So we only need 0.02-0.04% of the earths surface covered in solar arrays - not 85%.

I've read a square ten miles on edge to power the world. Naturally distributed rather all in one place would be best. Energy storage is also becoming better and better and cheaper and cheaper. Solar electricity is already cheaper that petroleum generated. California just went past a record 30 days only on renewables. Cheap electricity also makes possible the ending of water shortages. The surface of the earth is 70% water. Rich countries can already afford desalinization plants that can produce water at reasonable costs. And where I live the air is full of moisture and easy to extract with enough money.

 

[[DHT]Osiris]

I've read a square ten miles on edge to power the world. Naturally distributed rather all in one place would be best. Energy storage is also becoming better and better and cheaper and cheaper. Solar electricity is already cheaper that petroleum generated. California just went past a record 30 days only on renewables. Cheap electricity also makes possible the ending of water shortages. The surface of the earth is 70% water. Rich countries can already afford desalinization plants that can produce water at reasonable costs. And where I live the air is full of moisture and easy to extract with enough money.

Partially true, generation distribution is mandatory, since we don't have lossless power distribution. Desalination can definitely provide the fresh water required, but requires phenomenal amounts of power and very large systems if you really need to provide water to lots of citizens. That can obviously be powered with renewables but you're chasing more and more power that way.

 

[Paratus]

I've read a square ten miles on edge to power the world. Naturally distributed rather all in one place would be best. Energy storage is also becoming better and better and cheaper and cheaper. Solar electricity is already cheaper that petroleum generated. California just went past a record 30 days only on renewables. Cheap electricity also makes possible the ending of water shortages. The surface of the earth is 70% water. Rich countries can already afford desalinization plants that can produce water at reasonable costs. And where I live the air is full of moisture and easy to extract with enough money.

It should be more than 10miles on a side - probably more like 100-200 miles, but still a manageable amount especially when it makes up roof tops or providing shade where needed.

 

[Moonbeam]

It should be more than 10miles on a side - probably more like 100-200 miles, but still a manageable amount especially when it makes up roof tops or providing shade where needed.

Are you sure it’s not 100 Square Miles. Wait, maybe it’s 10 by 10 just for the US.

Speaking of shade where needed, solar can be produced with translucent greenhouse glass offering a twofer.

 

[IronWing]

It should be more than 10miles on a side - probably more like 100-200 miles, but still a manageable amount especially when it makes up roof tops or providing shade where needed.

Using the U.S. peak power demand from 2023, I come up with a 89 x 89 mile block of solar arrays required to meet peak demand. That assumes ~150kW/acre solar production which is the rate for one of the newer solar arrays in southern Arizona. The 89 x 89 mile block includes the service roads between the rows of panels.

 

[Paratus]

Using the U.S. peak power demand from 2023, I come up with a 89 x 89 mile block of solar arrays required to meet peak demand. That assumes ~150kW/acre solar production which is the rate for one of the newer solar arrays in southern Arizona. The 89 x 89 mile block includes the service roads between the rows of panels.

I think I did a back of the envelope calc for powering the entire world via solar assuming 7B people, some efficiency gains and using 40% efficient dual axis tracking arrays in good areas for solar like the US southwest and ended up with a square ~ 220Km x220Km on a side. So roughly the same ball park as you.

 

[hal2kilo]

Well, commercial scale collector arrays have a lower cost/m^2 than home systems. Semiconductor based solar cells can be a b*tch when it comes to efficiency at a reasonable cost, but considerable work is being done to improve efficiency and and eliminate the immediate efficiency drop off that occurs when solar cells are exposed to sunlight (which is kind of funny in a way).

Efficiency isn't so critical when the energy source is FREE.

 

[Ajay]

Efficiency isn't so critical when the energy source is FREE.

Yes, but solar panels are not free. Nor is the infrastures, of various sorts, required to collect, maintain and distribute that power.
I think we should rely heavily on renewables for the future, but I also think we have opportunities with modern fission reactors to provide the baseload power we need to install over the next 50 years. Battery storage (and other types) are important to overcoming the supply side variability of solar and wind. It's a combined attack approach.