So you want to build a carbon capture company • Hacker News Board

Re: So you want to build a carbon capture company

#121

Post by cogman10 » Tue, May 04, 2021, 1:45 PM UTC

jrnvs wrote: post #112

Burn biomass (plants) in a power plant to generate electricity, then store the carbon dioxide in empty gas fields. This is called BECCS, Bioenergy with carbon capture and storage [0]. Unfortunately, carbon capture and storage is not economical (yet). Let's hope it will be soon, with EU CO2 prices already reaching 50 euros / ton this week [1]. If I understand this International Energy Agency report[2] correctly, many…

Alternative, make charcoal, bury the charcoal, extract whatever useful thing you can from the not-charcol that comes from that process.

Charcoal is pretty much pure carbon and that's what we should be putting into the ground. Putting CO2 into the ground runs into problems because you have to deal with the fact that you are burying a gas (gasses don't like to be contained).

So skip that, and instead focus on burying pure carbon.

Re: So you want to build a carbon capture company

#122

Post by enriquto » Tue, May 04, 2021, 1:47 PM UTC

Beltiras wrote: post #110

mikro2nd wrote: post #94

Earlier quoted context omitted.

OTOH, growing plants, turning them into charcoal and sequestering that can be carbon-negative.

It's carbon-negative even if you don't count the buried carbon due to it being a powerful fertilizing agent.

I don't understand your remark. The plants that you are going to fertilize are part of a carbon neutral cycle anyway. It doesn't really matter if there is a big or small amount of them. The buried stuff is going to rot after a few years and release the carbon back.

I think the idea is to bury it to "geological" depths, forever isolated to the biosphere.

In the last century, we have burned millions of years worth of plant-based carbon sequestration. This was carbon that had been out of the biosphere for millions of years. Now our goal is to remove this carbon out of the biosphere again. I'm skeptical that this can be at all achieved by purely biological means. But burying dead plants a few meters deep, readily accessible to rot, is not likely to make any difference. Otherwise, we are going back to pre-cambrian CO2 levels, which were much higher than today.

Re: So you want to build a carbon capture company

#123

Post by vlovich123 » Tue, May 04, 2021, 1:53 PM UTC

wodenokoto wrote: post #85

Aerroon wrote: post #67

Earlier quoted context omitted.

The ecosystem is more or less in a balance. Forests that are cut down will become forests again. Plants already grow pretty much everywhere where they can grow. It's still not enough. We've spent over 200 years pumping carbon into the atmosphere from a source we can't return it to. No amount of growing forests is going to fix this issue without being able to turn those forests into carbon that's in the ground. We nee…

You’re so close to saying the solution without getting there. Fast growing plants are probably the most effective carbon extraction we have. Problem is when they die they turn back into CO2. So we should bury those plants before they rot. Our excess CO2 stems mostly from dead plants and animals that have been buried. Seems sensible to put some of our excess back into the ground.

Which requires digging. Which requires machinery at an industrial scale. Which requires large amounts of energy. Which makes it really hard for this to not be in the perpetual motion set of solutions.

You’d have to be extracting more carbon than your diggers consume (since even today I don’t think this has electrified and capable of running on solar). Your diggers are consuming concentrated carbon compressed from plant and animal biomass under high pressure and energy over millions of years. It seems highly unlikely just growing and burying biomass is sufficient. Additionally, I’m pretty sure the CO2 is just going to leak out in large quantities since, unlike the naturally sequestered CO2 we extract from the ground, you have bacteria that can break down the biomass and let the CO2 escape as a gas. Which means we have serious additional efficiency losses.

The only solution that could work for sequestration as far as I can tell seems like an industrial process powered by nuclear because it breaks the energy cycle completely to accomplish the task. Solar is popular but I’m skeptical that renewables are up to the task that’s required to undo several hundred years of fossil fuels being the engine of the world’s industrial progress.

Re: So you want to build a carbon capture company

#124

Post by pjc50 » Tue, May 04, 2021, 1:55 PM UTC

f00zz wrote: post #120

pjc50 wrote: post #41

Earlier quoted context omitted.

Given the astronomical amount of energy required for launch, this will almost certainly never even break even on energy.

The idea in those 1970s proposals was to build power satellites with materials mined on the Moon. I guess this sounded more realistic back when the Apollo landings were still within living memory.

OK, so add the cost of building a lunar factory and the breakeven gets worse, not better.

(Most of the 1970s proposals are basically pleas for funding with cool Syd Mead concept art attached, they were never mathematically feasible even in their own era without some other breakthroughs)

Re: So you want to build a carbon capture company

#125

Post by gonzo41 » Tue, May 04, 2021, 1:55 PM UTC

cogman10 wrote: post #121

jrnvs wrote: post #112

Burn biomass (plants) in a power plant to generate electricity, then store the carbon dioxide in empty gas fields. This is called BECCS, Bioenergy with carbon capture and storage [0]. Unfortunately, carbon capture and storage is not economical (yet). Let's hope it will be soon, with EU CO2 prices already reaching 50 euros / ton this week [1]. If I understand this International Energy Agency report[2] correctly, many…

Alternative, make charcoal, bury the charcoal, extract whatever useful thing you can from the not-charcol that comes from that process. Charcoal is pretty much pure carbon and that's what we should be putting into the ground. Putting CO2 into the ground runs into problems because you have to deal with the fact that you are burying a gas (gasses don't like to be contained). So skip that, and instead focus on burying p…

This is a good idea, But getting the biomass will be difficult. I dream about large lakes of algae that can be skimmed and then sundried, and cooked in solar ovens to create essentially a solar powered only capture process.

This sort of operation would need a stable cap and trade or carbon tax system to be profitable.

I should also add, I think China or somewhere in the hot parts of Africa would be a a good place for this as it would be a large area operation. Sadly as an Australian we suffer from regulatory capture and a carbon tax won't be back on the cards for some time.

Re: So you want to build a carbon capture company

#126

Post by wildmanx » Tue, May 04, 2021, 1:57 PM UTC

WhompingWindows wrote: post #117

Why not use reduced space-flight costs to lift giant solar reflectors to prevent our poles and ice-caps from being melted? It wouldn't affect insolation at agricultural centers and it would slow warming enough for us to get carbon capture cheaper.

Global climate is more than just average temperature. Or even "prevent ice caps from melting". It's an insanely complex system that we have only started to understand. There are currents in the oceans and the air, they have complex interdependencies, even with vegetation.

If you change this, you may end up screwing up the climate even more.

Re: So you want to build a carbon capture company

#127

Post by barathr » Tue, May 04, 2021, 1:57 PM UTC

If a machine were invented that scrubbed carbon from the atmosphere and turned it into useful food, construction materials, animal feedstocks, and fibers, all while rebuilding topsoil, it would be on the cover of every tech magazine in the world and its inventor would be a celebrity millionaire. Yet I’ve never seen a tree on the cover of Wired.

https://hipcrime.blogspot.com/2012/06/vertical-farms-and-lab...

Sometimes we overlook the simplest approaches. We should plant trees. Lots of them. It's not a perfect solution, but it's the simplest, can be adapted to every environment, has costs that are relative to local economies, doesn't depend upon global supply chains, doesn't require human maintenance after initial planting, etc.

Re: So you want to build a carbon capture company

#128

Post by SyzygistSix » Tue, May 04, 2021, 2:03 PM UTC

chr1 wrote: post #82

Aerroon wrote: post #67

Earlier quoted context omitted.

The ecosystem is more or less in a balance. Forests that are cut down will become forests again. Plants already grow pretty much everywhere where they can grow. It's still not enough. We've spent over 200 years pumping carbon into the atmosphere from a source we can't return it to. No amount of growing forests is going to fix this issue without being able to turn those forests into carbon that's in the ground. We nee…

Not only forests, but converting a desert, like Sahara, into agricultural land will help too. Same is true for ocean deserts, places where there is no upwards flow bringing nutrients from ocean floor to the surface, which is the majority of the ocean.

I think the math has been done for this and the CO2 captured by planting the Sahara would be offset by the increased warming due to the reduction of albedo effect. Which is crazy to think about.

Re: So you want to build a carbon capture company

#129

Post by DennisP » Tue, May 04, 2021, 2:10 PM UTC

cagenut wrote: post #101

senko wrote: post #95

Armchair strategizing on the topic I know nothing about (but it's fun to think about!): Constraints: - C removal requires lots of energy (can't avoid thermodynamics) - electricity on that scale is either expensive, dirty, or both Additional concerns: - cheap/clean energy is intermittent (and still a small percentage) - excessive electricity is as bad as not enough electricity Solution: - build lots of new (safe and c…

I really like your idea on a personal 'neat' would-be-nice level, but it makes one of the most common mistakes in the nuclear climate-change discussion: time. The development of next-gen/thorium/msr/whatever from first-commercial-success to repeatable-and-therefore-cheaper is, even in a highly optimistic scenario, a 30+ year proposition. I fervently believe we should fund and invest in that r&d, but even if it pans o…

Yes, if we rapidly decarbonize to renewables and figure out the storage issue, we don't need nuclear. And we should certainly attempt that. But if we overshoot, like in that P4 scenario, we're going to need massive carbon capture down the road, and nuclear fits quite well into that scenario.

Also, if storage remains expensive at scale, so that wind/solar gets very expensive past 80% market penetration, nuclear would be a low-carbon way to fill in that last 20%. It doesn't do away with the need to roll out wind/solar as fast as we can, but it helps us with the hard part later.

Nuclear also may be well-suited for industrial applications requiring process heat instead of electricity.

Re: So you want to build a carbon capture company

#130

Post by SyzygistSix » Tue, May 04, 2021, 2:12 PM UTC

wildmanx wrote: post #126

WhompingWindows wrote: post #117

Why not use reduced space-flight costs to lift giant solar reflectors to prevent our poles and ice-caps from being melted? It wouldn't affect insolation at agricultural centers and it would slow warming enough for us to get carbon capture cheaper.

Global climate is more than just average temperature. Or even "prevent ice caps from melting". It's an insanely complex system that we have only started to understand. There are currents in the oceans and the air, they have complex interdependencies, even with vegetation. If you change this, you may end up screwing up the climate even more.

The reduction of the albedo effect from the disappearing ice at the poles is a considerable cause of global warming.