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Comment by hannob | Hacker News Reader

This starts to sound right and at the end takes the completely wrong turn when he says: "I especially like the idea of CO2 scrubbing for coal-fired power plants."

I actually believe this is the big risk of all Carbon removal and Carbon Storage technologies, and the one that always needs to be kept in mind: That they're used to justify the continuing use of fossil fuels. (This isn't theoretical. This happened around 10 years in Germany when many new coal plants were built, and when people brought up the climate issue a very common answer was: "Don't worry, we already planned to enhance those plants with Carbon Capture and Storage technology later." Of course the latter never happened. At around the same time Norway had very similar discussions and I'm sure it happened elsewhere, too.)

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Yeah. You need at least as much energy to turn co2 into carbon (and oxygen) as you got from burning it in the first place.

Scrubbing coal powered plants takes away the whole point of the coal plant because you end up with negative energy.

Why would they even need to turn it back? I'm sure some of it might be salvageable but I thought the point was more towards just containing it.

Containing a yearly supply of tens of giggatones of a gas that has very little commercial value seems orders of magnitude less practical than actually avoiding producing that gas in the first place.

That's what geological storage is all about. After all, the carbon came from the ground in the first place.

The coal came from the ground. Not the carbon-dioxide.

Not saying that it's impossible or even impractical to store co2 underground. It just seems like a proposition that has a lot to prove.

People may have different motivations for promoting CCS (carbon capture and storage). However, the underlying motivations for a subgroup of those promoting a technology shouldn't be a reason for dismissing the technology itself.

I agree that CCS shouldn't be used as an excuse to continue fossile fuel use. However, as long as there are fossile power plants in existence (and we are necessarily stuck with those for a very long time), it makes infintely more sense to capture emissions at the source (the power plant) rather than spending energy capturing CO2 out of "thin air" later.

Moreover, there are a host of industries (steel, cement, chemicals) that would continue emitting large amounts of CO2 even if they switched 100% to renewable energy). To cut these emissions, there is no alternative to capturing the CO2 and storing it.

Looking at the figures, I would dare to claim that people against the use of CCS are not really serious about tackling climate change. (And by the way, the reason large-scale CCS has not yet happened in Europe is to a large part public resistance - I would assume that's a big part of the reason for those power plants in Germany too).

I agree with #hannob to a point.

I favor any approach that can be done now to make an improvement. We need to reduce, then eliminate atmospheric CO2 production and then get to reversing - removing it - ASAP.

It's up to us to make sure First Steps aren't seen as Only Steps - but that certainly doesn't mean we shouldn't take them.

Yeah, that 's one of those things in which everyone involved needs to be held to account - if the promise is based on CCS, then the plant must not be allowed to turn on without it.

Generation with CCS is not impossible, it's just .. uncompetitive with renewables.

Is continuing to use fossil fuels a bad thing, if it's in conjunction with sufficient cleanup systems? It sounds like in your example, the problem is the bait-and-switch from "clean CO2-neutral power plants" to "traditional coal power plants".

The question is how you're going to cleanup CO₂, which is almost always energy-negative.

Coal plant emissions contain toxic substances other than CO2. Also consider the fly ash disposal and the environmental disruption of mining.

So, yes, aside from CO2, continued energy production using coal is an unsustainable strategy.

Stopping fossil fuel burning is always preferrable to carbon cleanup technologies. It's simply cheaper and easier.

Also "CO2-neutral coal power plants" is a scam. You'll always have emissions left. Digging up coal causes emissions (the coal is not alone, there's e.g. always methane coming up with it that you can't capture). No Carbon removal tech can remove 100% of Carbon from emissions. (There was actually a lawsuite because Vattenfall called one of their CCS testing plants "carbon free". They lost.)

You need about 1.5-2x the amount of coal to provide the energy for the clean-up systems. So you can expect politicians to "increase efficiency and reduce dependence on foreign coal" by turning them off.

Also, I can't find figures easily but it still wouldn't be as clean as solar, nuclear or wind.

> Is continuing to use fossil fuels a bad thing, if it's in conjunction with sufficient cleanup systems?

You missed the point. The problem in the grandparent post isn't with the first clause, it's not even with the feasibility of the second clause.

It's with the "if". The "if" won't happen in practice. So that makes the answer to your question "no".

Exactly. The tl;dr of the article is: "I agree that carbon scrubbing is used to justify continued emissions, and that's not good, now let me advocate for carbon scrubbing and not talk about what we really need to do."

Let me put it simply: we need to stop burning fossil fuels NOW (move to renewables) and also have less kids (1 or 2 per couple). Anyone with the means should use solar PV, wood heat, electric cars, and reduce air travel to once per year. This means you most likely need to change from what you grew up with and what you know and how you live. We all need to change, our economy needs to change, and we need to acknowledge that as soo as possible; the lives of outer children depend on it.

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