cat botherer posted:

I doubt they treat irrigation water with anything, but yeah, irrigation runoff is really bad. Things like no-till farming, and substituting manure for phosphates and nitrate fertilizers can help a lot in reducing water pollution, and help avoid water wastage.

TheMuffinMan posted:

have you guys heard of cold fusion

TheMuffinMan posted:

regarding nuclear fusion power out vs power in (the Qext represents that ratio below)

"The record for Qext was held by JT-60, with Qext = 1.25, slightly besting JET's earlier Qext = 1.14. In December 2022, the National Ignition Facility reached Q = 1.54 with a 3.15 MJ output from a 2.05 MJ laser heating, which remains the record as of 2023"

M_Gargantua posted:

Raenir Salazar posted:

IIRC the NIF is also using really old lasers and the facility as a whole is more about weapons related research than about working on a civilian/commercial reactor. It'd be interesting to see how far they could push the envelop using modern technology and engineering based on everything learned with much more efficient lasers and so on. Maybe if that room temp superconductor works out maybe that can help.

TheMuffinMan posted:

"Over their 50-year history, lasers have gone from producing powers of a few hundred watts to greater than a petawatt, or a quadrillion watts. Several key technological jumps have allowed researchers to compress laser beams into infinitesimally short pulses, which amplifies their peak power"

one petawatt has 1,024 terawatts

Raenir Salazar posted:

I don't think you're responding to what I'm saying; you post indicates indicates that lasers for sure have gotten more powerful which isn't what I'm talking about?

TheMuffinMan posted:

what

Raenir Salazar posted:

I'm not sure I understand where the confusion is coming from, perhaps can you explain with some of your own commentary or provide the argument that the quote you posted is meant to support? Maybe we're talking past each other here.

Infinite Karma posted:

There are a few, off the top of my head. Fresh water is still a limited resource. Technology to store H2 long-term isn't great - the molecule is so small that it's very hard to contain without substantial leaks. Pure H2 and pure O2 are very valuable for non-energy generation uses, so burning them to create energy isn't economically smart.

TheMuffinMan posted:

what is pure H2 and O2 needed for besides energy production

TheMuffinMan posted:

i saw a video over 10 years ago about how orange country in California recycled their water. I think it was greywater.

one of the last steps was blasting the water with UV Radiation to help kill the bad stuff. they said the final result was drinkable water.

TheMuffinMan posted:

what is pure H2 and O2 needed for besides energy production

DTurtle posted:

Pure H2 is expected to replace coal in steel production.

TheMuffinMan posted:

one petawatt has 1,024 terawatts

Kalman posted:

It’s not a loving SSD, it uses the correct units.

1 petawatt is 1000 terawatts.

TheMuffinMan posted:

regarding nuclear fusion power out vs power in (the Qext represents that ratio below)

"The record for Qext was held by JT-60, with Qext = 1.25, slightly besting JET's earlier Qext = 1.14. In December 2022, the National Ignition Facility reached Q = 1.54 with a 3.15 MJ output from a 2.05 MJ laser heating,

quote:

which remains the record as of 2023"

TheMuffinMan posted:

gently caress.

Kalman posted:

It’s not a loving SSD, it uses the correct units.

1 petawatt is 1000 terawatts.

mobby_6kl posted:

Storage is measured in base-10 units!


The fixed statement would actually be
one pebiwatt has 1,024 tebiwatts

TheMuffinMan posted:

omg

DTurtle posted:

Why?
Currently CO2 is the byproduct. In the future it will be H2O.

TheMuffinMan posted:

uhmmm

DTurtle posted:

If you write complete sentences, it might actually be possible to have a conversation .

TheMuffinMan posted:

yeah well if you don't project random poo poo my way, it might be possible to have a conversation

cat botherer posted:

https://www.mining-technology.com/news/green-steel-hydrogen/

There’s H2 steel plants already under construction. It’s a thing.

Discendo Vox posted:

My understanding is that concrete production also has a terrible emissions profile. Is there similar development in that direction?

mediaphage posted:

yeah cement is like two and a half percent of co2 production. i’m no expert but aiui there’s nothing currently to be done as part of the process involves using heat to convert CaCO3 to CaO and CO2. site you could use a fossil-free heat source but you’re still stuck with that conversion issue

i’m sure there are people working on carbonate alternatives or perhaps another means of conversion by which the co2 is captured within the final prodiuct but i dunno how that would affect strength. additionally since this is done in giant kilns perhaps ultimately this is a situation where carbon capture might actually work but i guess i’m not holding my breath on that

mobby_6kl posted:

There's definitely been some noise about carbon-neutral concrete production:

https://www.popularmechanics.com/science/green-tech/a40785162/microalgae-carbon-neutral-cement/

I don't know enough about this stuff to pretend like I'm an expert but seems like there are some possibilities there.

quote:

David Roberts

I want to get a sense of scale before we move on from the process. Sort of if I'm producing concrete and I'm using your process to inject CO2, say I do both of the available options and I get CO2 injected into my wastewater and I get CO2 injected into my mixer, is the end product of that carbon negative or how close is it to carbon negative? Give a sense of scale, like how much of the carbon in the process is being offset by this?

Robert Niven

Yeah, it's one piece of the pie. To get to carbon negative or neutral concrete is we're going to need some substantial changes on the cement side as well. And there are some fellow companies within our investors portfolio. A great example would be like a Brimstone who are working on the cement side. We're working with whatever cement is coming down the line and we're adding if you sort of combine the reclaimed water and ready mix, you're getting another 10% to 15%. But that's 10% to 15% off of a global commodity with a huge volume and we can do it today with very little CapEx and it's permanent.

So if you think about a marginal abatement cost curve, it's like this is the furthest left on that curve. This is the thing that is easy to implement at scale. It has a significant percentage reduction, but off of a huge number, the volume of concrete is enormous. There's about 40 billion tons of concrete produced or 4.2 billion tons of cement.

David Roberts

And what's the number? I think it's 8% of global emissions, something like that.

Robert Niven

We use the word the number 7% and most of that's cement. And the reason it's so big is because so much concrete is being used, it's second only to drinking water in production. Yeah.

David Roberts

So you can take 10% to 15% of the CO2 basically out of the final product, but more than that is going to require deeper changes in the process.

Robert Niven

And that doesn't include our aggregate technology. So that will layer in a lot more. But we need to work together all the way along the value chain. The traditional cement sector are doing things like they're using supplementary cementitious materials instead of cement and that means using things like fly ash and slag. The problem is those materials are declining in availability, they're doing things like fuel switching, so using waste materials, energy efficiency, all those traditional things should be done. But then there's also some real deep tech stuff going on right now about fundamentally changing the cement process or chemistry.

But that's going to take a lot of money and we still have a lot of time ahead of us. So we need to get going today on those immediately deployable solutions.

mediaphage posted:

like i said i’m sure people are working on it. but also: i’m curious to know how they define that cement process as carbon neutral. like ok you’ve managed to grow your corals. that’s still CaCO3 and not CaO isn’t it?

so maybe it’s a better source of the underlying calcium carbonate (we’ll ignore the carbon emitted during the implementation of this process as a one-time sink, say) and once we get our two million acres of ponds rolling we can use this biogenic limestone in the process. but on the whole it seems like a long way from being carbon neutral and i don’t know where the article is pulling the rest of the information from that you’d need to make that claim

Electric Wrigglies posted:

I think that rather than digging up fresh CaCO3 and liberating new CO2 to the atmosphere, Their theory is that you instead grow your CaCO3 and hence have a cycle of carbon going from air, to water, to limestone (grown via algae) to CO2 (via calcination, the created CaO going on to become cement) in the air again. It could be negative if it does not recovery all the CaCO3 grown in the cycle (which would be expected not many processes have 100% recovery).

I guess it assumes that plenty of Ca is available in the water and I hope they mean in seawater.

E) and further, I think processes that recovery carbon from the atmosphere (or via seawater) for industrial use would be excellent shortcut to sequestration. For example, if plastics and fuel are produced with atmospheric carbon, nearly always a portion will be converted to a solid (soot, buried plastic waste, etc) and consequently removed from the atmosphere on a longer timeframe, even it is only 100 years it will be of benefit now.