Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline • Hacker News Board

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#561

Post by seppel » Tue, May 07, 2019, 7:42 PM UTC

CryptoPunk wrote: post #395

seppel wrote: post #383

Earlier quoted context omitted.

My personal pet theory is that the energy consumption is more or less equivalent to the price. So as long as the solar panel is not economically viable, it does not provide an energy surplus. 20MWh is not much, it's $500-$3000 worth of energy, depending on taxes and stuff. Can you buy, install, connect, maintain, clean a 300W solar panel for 20 years for this price? Edit: Also, 20MWh is quite high. That's 9h of perfe…

If that were true, the cost of the energy consumed would be equivalent to GDP, and that is not the case.

That a good point. But a huge part of the GDP increase is an increase in efficiency, i.e., you can do more with less energy. A 2019 computer would cost a totally different price in 2009, and would be infeasible expensive in 1999.

But if you compare technologies within one year, the price tag gives you a very good idea how much energy was used for producing each one. Of course, there are scale effects at play, so an R&D cost (energy) might only occur once, but is then distributed within all units produced. This will very well be reflected in the price, once something enter mass market.

The same will happen with photovoltaic cells: They will continue to get cheaper (and more efficient) and at one point it will make economic sense to put them everywhere. And at this point it is clear that they are net energy producers, where currently it is still debatable, at least in more northern regions.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#562

Post by mazlix » Tue, May 07, 2019, 8:05 PM UTC

_Nat_ wrote: post #320

Why open-air capture? I mean, it's typically much cheaper to capture CO2 from concentrated streams, such as the flue gases from coal-fired power plants. So why accomplish the same CO2 mitigation at higher cost by getting it from open-air capture?

I don't see how that will economically make sense long term. Burn coal to yield co2 + water + electricity, then use electricity to convert the co2 + water into oil? I assume it's more efficient to directly convert coil to oil: https://en.wikipedia.org/wiki/Coal_liquefaction

What they're doing makes more sense to my intuition. "Mine" (excess) co2 from the atmosphere, using a cleaner source of electricity.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#563

Post by _Nat_ » Tue, May 07, 2019, 9:05 PM UTC

mazlix wrote: post #562

_Nat_ wrote: post #320

Why open-air capture? I mean, it's typically much cheaper to capture CO2 from concentrated streams, such as the flue gases from coal-fired power plants. So why accomplish the same CO2 mitigation at higher cost by getting it from open-air capture?

I don't see how that will economically make sense long term. Burn coal to yield co2 + water + electricity, then use electricity to convert the co2 + water into oil? I assume it's more efficient to directly convert coil to oil: https://en.wikipedia.org/wiki/Coal_liquefaction What they're doing makes more sense to my intuition. "Mine" (excess) co2 from the atmosphere, using a cleaner source of electricity.

That's what makes this so interesting!

I mean, if open-air capture is used, it's mostly just a higher cost -- switching to capture from point-sources should make it more efficient. But then it seems to demolish folks' evaluation of the proposal itself.

I suspect that it's that "mining CO2 from the atmosphere" concept that, when we talk about open-air capture, makes it feel like a closed-loop process. But when we talk about capture from point-sources, it seems to feel less like a closed-loop process, leading to a loss of that intuitive feeling you'd mentioned above.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#564

Post by pfdietz » Tue, May 07, 2019, 9:59 PM UTC

seppel wrote: post #560

pfdietz wrote: post #495

Earlier quoted context omitted.

"My personal pet theory is that the energy consumption is more or less equivalent to the price." This implies that energy is the only input to making PV, which is clearly wrong. Or maybe you're saying that if we trace back costs into the economy, from the workers, to the grocery stores where they buy their food, to the farmers, etc. etc., it all eventually comes back to energy. In that case the energy return on inves…

> Or maybe you're saying that if we trace back costs into the economy, from the workers, to the grocery stores where they buy their food, to the farmers, etc. etc., it all eventually comes back to energy. Yes. Of course, this is greatly simplified and I'm not entirely sure where to put capital costs in my theory. But I think I'm not too far off. And of course I'm purely talking about energy, not whether it is environ…

It means that if you trace economic activity back to the point that it involves energy, ALL economic energy eventually traces back to energy. The EROEI becomes 1, by definition.

Of course this is ludicrous. If you double the energy efficiency of all activities, and cut the energy used in the economy by half, these long chains get longer, but they still end at the energy production, so that '1' doesn't change. What this kind of evaluation misses is the massive multiple counting going on: that displaced energy use is producing value all along the chains, and the longer the chains, the more value each unit of energy produces.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#565

Post by danieltillett » Tue, May 07, 2019, 11:34 PM UTC

mrob wrote: post #503

danieltillett wrote: post #492

Earlier quoted context omitted.

No. I think you really need to understand Jevon's paradox. I highly encourage you to do so - once I learned about it so much of the world became clearer.

The price does not need to be below the marginal cost of production of fossil fuel. It only needs to be below the cost of production + the cost of taxes on fossil fuel. I suggest that a taxation level that allows Jevons paradox to occur is too low.

Taxes on fossil fuels just raise the marginal cost of production. They are a totally separate issue from the effect of introducing a new fuel into the market.

Given the amount of down voting I have received basic economics is not popular on HC. Increasing the supply of gasoline will reduce its price which will cause increased demand greater than the original supply. The original example used by Jevon was coal consumption which rose 10 fold as the price halved. If Promethus succeeds they will cause an increase in consumption of fossil fuels (assuming no other changed) as they will lower the price of gasoline increasing its consumption.

The only way that such an approach can work is if they can get the price of gasoline below the cost of production from fossil fuels. While this may be possible, on thermodynamic grounds it is hard to compete with all the stored sunlight in fossil fuels, let alone the sunk costs in the fossil fuel infrastructure.

I am very much in favour of doing something about us burning fossil fuel, but I want us to concentrate on those things that make economic sense. In respect to gasoline that would be electrification of the transport system and better electric storage.

The one thing that would potentially be worth pursuing is not the production of gasoline, but avgas (diesel) as there really is no viable alternative to these for air and sea transport.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#566

Post by stephen_g » Wed, May 08, 2019, 1:43 AM UTC

salv0 wrote: post #500

brilee wrote: post #428

A few questions from a chemistry major 1. why extract from the air when you can just put a device on the smokestack of an existing coal or natural gas plant? The higher CO2 density of the effluent will make things more efficient. 2. Your key innovation isn't the part where you pull CO2 out of the air; it's the nanotube-based reverse osmosis process for separating ethanol from water. This process could just as easily…

But then, why to use solar energy to convert CO2 into fuel when you can convert the solar energy into electricity directly and remove the need for the fossil fuel based power plants?

This question is probably answered literally more than a hundred times in this comments section!

We have a huge fleet of cars, trucks, planes and ships that are all very carbon-positive. We also have a huge amount of existing infrastructure for delivering fuel to these things.

Sure, cars and trucks could go electric, but large airliners probably never can, and it's difficult for ships. But even for cars it will take decades to fully transition to electric. An economically viable, carbon neutral fuel that could be brought to market and scaled up quickly would be a huge win for the transition. Especially if it's cleaner burning (no/very low sulfur, aromatics etc.).

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#567

Post by acidburnNSA » Wed, May 08, 2019, 3:34 AM UTC

pfdietz wrote: post #493

acidburnNSA wrote: post #442

Earlier quoted context omitted.

Hook to nuclear and hydro electricity and you can get your uptime much higher while remaining carbon free. That should give you a good 2x boost on capex at least.

Building nuclear plants to save on electrolyzer capital cost is not a good idea at all. Penny wise, pound foolish.

Hook to existing plants to help them load follow where intermittent renewables are at high capacity.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#568

Post by sova » Wed, May 08, 2019, 5:24 AM UTC

simonh wrote: post #553

rmcginnis wrote: post #547

Earlier quoted context omitted.

Yes, we're actually agnostic on CO2 source. To get to scale we'll need to use CO2 from direct air capture, but we could by the collection from someone else.

I can completely see the logic. If this only works for point sources it may not scale sufficiently to be viable long term. So that capability needs to be proved out early in order to demonstrate it's long term value to investors.

how many point sources do you need to make atmospheric extraction viable? i'm thinking it's like a million

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#569

Post by mrob » Wed, May 08, 2019, 6:58 AM UTC

danieltillett wrote: post #565

mrob wrote: post #503

Earlier quoted context omitted.

The price does not need to be below the marginal cost of production of fossil fuel. It only needs to be below the cost of production + the cost of taxes on fossil fuel. I suggest that a taxation level that allows Jevons paradox to occur is too low.

Taxes on fossil fuels just raise the marginal cost of production. They are a totally separate issue from the effect of introducing a new fuel into the market. Given the amount of down voting I have received basic economics is not popular on HC. Increasing the supply of gasoline will reduce its price which will cause increased demand greater than the original supply. The original example used by Jevon was coal consump…

>Increasing the supply of gasoline will reduce its price

This is not an inevitability. The state can and does tax things, and I am suggesting that they should tax fossil fuels sufficiently to prevent Jevon's paradox from happening. The correct taxation to prevent the market failure of externalities is not any percentage of the production cost, it's the cost of the harm done. If Jevon's paradox would increase the harm done then tax should increase to prevent this.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#570

Post by danieltillett » Wed, May 08, 2019, 9:11 AM UTC

mrob wrote: post #569

danieltillett wrote: post #565

Earlier quoted context omitted.

Taxes on fossil fuels just raise the marginal cost of production. They are a totally separate issue from the effect of introducing a new fuel into the market. Given the amount of down voting I have received basic economics is not popular on HC. Increasing the supply of gasoline will reduce its price which will cause increased demand greater than the original supply. The original example used by Jevon was coal consump…

>Increasing the supply of gasoline will reduce its price This is not an inevitability. The state can and does tax things, and I am suggesting that they should tax fossil fuels sufficiently to prevent Jevon's paradox from happening. The correct taxation to prevent the market failure of externalities is not any percentage of the production cost, it's the cost of the harm done. If Jevon's paradox would increase the harm…

There is no need to have some alternative gasoline in order to implement a tax to decrease consumption of gasoline. Just a straight carbon tax would do this. The problem of course has been getting these implemented.

We really should keep the topic of what Prometheus wants to do seperate from other things like carbon taxes.

I think the best bang for our buck would be to just buy the oil before it is pumped out of the ground and leave it there. The producers would stop fighting us doing something about climate change and the increase in gasoline prices would drive the adoption of carbon neutral energy sources.