60 points | by geox1 day ago
Boats consume way more fuel than a layman may think. I’ve been on a ~80m / 20people crew coast guard ship for 6 weeks and did a napkin math onboard based on tank levels and refueling date. It was +1000l/person/day of diesel (can’t remember precise numbers). We were moving ~50% or the time. In addition of the motors there were many BIG generators to make everything work: heating, sewage, hot water, AC, pumps, motors for cranes, anchor raising… you also need your motors running at least in low speed even when still to control your position and direction.
I’m sure boats acting like platforms and with less crew to accommodate does consume less, however it’s still nothing comparable to an onshore plant.
It work "economically" because you often manage to refuel in an port with low fuel price.
I read a proposal for an air extraction system that fit in a container, so that you could stack a few on a container ship and they would process air as they went from port to port. Typically power challenged though (you want some clean energy powering them). Nuclear powered container ships would be good for this.
> Captura’s Port of Los Angeles pilot can remove about 100 tonnes of CO2 per year from seawater. The company’s new plant under construction in Hawaii will capture 10 times that amount—a measurement the company can definitively quantify.
So 1,000 tonnes of CO2 / year?
https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-t...
Meh, words. /s
It's like the butterfly effect applied to complex systems, if you do something big enough for causing a change it will probably affect a lot of things, most that will be obvious only on hindsight, and by Murphy it will end being something essential. Like what happened with the mandate of reducing the sulphur content in ship's fuel oil.
> If you want to strip out 1 gigatonne of CO2 from the ocean, you probably have to put the upper few meters of the Atlantic through your machines every year
That sounds…drastic! And this seems quite hand-wavy about the risks:
> a lot of environmental monitoring needs to be done to prove that marine carbon-removal strategies aren’t harming aquatic life
This skips a lot of important steps that likely cannot fit on one ship, but I love the idea of it.
But you're right: Just put a off-the-shelf modular reactor on the ship, then use that power to synthesize payload fuel from CO2, and the gold, uranium, etc are just helpful extras.
https://www.lesswrong.com/posts/rHBdcHGLJ7KvLJQPk/the-logica...
Irrigation has destroyed entire seas, crop pests have been near exterminated only to learn those pests were eating far more dangerous pests - resulting in mass starvation, and so on endlessly.
This entire idea really seems like the sort of action we're really not thinking through. Even the article points this out... "What’s not easy to quantify is what happens after the CO2-depleted effluent is returned to the sea. Theoretically, if.." To say nothing of the million other possible issues mostly just handwaved away.
And interesting website in general, thanks for sharing!
There's hard sci-fi, for starters. Even outside that realm, nothing wrong with using them as cautionary tales. Asimov's tales excel at this, even if they're not "physically accurate"; who tf cares about that, honestly.
No one in their right mind would treat this literature as if they were textbooks.
There has to be some other, unannounced benefit to funding these things like contributing research insights to naval warfare problems.
We also probably benefit from geoengineering regardless of what happens to CO2 production (depending on whether we think the weather was better a few decades ago or not).
Artificial weathering is the only approach that I’ve ever read anything remotely convincing about.
But say we did manage to get massive amounts of organic matter into the deep ocean, we could feasibly end up creating a so-called "dead zone" that is depleted in oxygen like we see elsewhere in the ocean, which would be detrimental to deep sea life.
Processing millions upon millions of cubic kilometres (top 5m of the sea is a bit under 2 million) through machinery just screams science fiction or greenwashing to me, simply based on "you want how many pipes?!". Current human water use is 4000km^3/yr: so it's 500 times more than that to cycle the water once.
If we could build that much processing infrastructure, we could just build decarbonised generation capacity in the first place. IEA estimates that 150ish GW of nuclear power would displace 1Gt, or maybe 600GW of solar. That's way less than pumps and handling plants for 100 Lake Baikals per year. China installed a third of that in just solar this year.
https://www.iea.org/data-and-statistics/charts/annual-direct...
That said, I doubt any of this will be stopped in time. Our governments (state and federal) aren’t even quick enough to understand the impact of offshore wind farms on marine life. These geoengineering projects are far more complex and have less data available. So I think the default is that they’ll continue.
So long as money keeps flowing into this ridiculous industry and politicians keep using FUD to drive their voter-base, the flow of nonsensical non-solution will not stop.
It is inevitable that, at some point in the future, people will finally understand reality for what it is.
As an example, it has taken around twenty years for people to finally start understanding the scale of the energy problem we have in order to support full electrification of ground transportation. And now, with AI data centers likely doubling that requirement, this is finally leading to the --surprise!-- conclusion that nuclear power is a necessary solution. I have been brutalized here on HN in the past for daring to (years ago) bring-up the simple math related to the EV problem. Today we are at a point where the issue is starting to float to the surface. That took about twenty years. The math was the same back then. It's just that people refuse to think past what is being shoved into their heads from every angle.
The next bridge to cross is the carbon removal scam. It will take time. I get it. People will eventually understand. I just hope we don't do irreparable damage to entire ecosystems between now and then.
A) It’s easy for a typical US family of four to net produce electricity with about 800-1000 sq ft of solar panels, assuming all electric appliances and vehicles (with reasonable commutes). The EV’s are basically rolling powerwalls, so this solves the storage problem.
B) Some of the direct air capture systems rely solely on industrial processes that we know how to scale. They target ~$1-2 to remediate a gallon of burnt gas. (They haven’t scaled quickly yet because no one with enough money has placed a big bet on them.)
I also think we should invest heavily in nuclear, and think most of the current carbon removal schemes are frauds, fwiw.
Not really. Our solar array is almost 900 square feet (4 x 20 meters). However, most people, even those with solar, have a misconception about the realities of solar power. This, because most people don't have technical backgrounds and never really look at their systems analytically. And, BTW, most arrays are significantly smaller than this one.
For example, this is what the array can look like on a good day:
https://i.imgur.com/aNnbmDp.png
This is what it can look like during a cloudy day:
https://i.imgur.com/breTHQd.png
Yes! Those are white puffy clouds in sunny southern California!
I have posted the math here on HN in detail in the past. The idea of using your EV as a battery simply will not work on multiple fronts. One of the most basic problems is that you'd age your battery prematurely by adding charge/discharge cycles. Need to travel somewhere? Too bad, your battery is down to 25% because it was powering your home. The reality of the situation is that you need many times the storage that an EV is able to provide in order to deal with the unreliability of solar production.
If I remember correctly, when I did the math for our system, the conclusion was that we would have to triple the size of the array and have over 400 kWh of storage in place.
The effects of unpredictable weather events and just plain clouds during otherwise beautiful sunny days makes this problematic. We had a particularly rough set of days in January of 2023 (and other times, I just have screen grabs for that period):
https://i.imgur.com/bo0s7b0.png
It is quite sobering to do the math for what it would take to mitigate this. Adding EV's to charge at home to this equation makes it even worse.
> Some of the direct air capture systems rely solely on industrial processes that we know how to scale.
When you add-up the realities of manufacturing (which in some cases might include mining), transportation, construction, deployment, operations and maintenance, not one system has yet surfaced that can conclusively operate beyond the lab or, at best, a small test area (like a small farm patch). It is quite a different matter to operate at a the scale of a city, province/state, country and globally. I'd love for it to work, but, so far, everything is in the category of a fantasy.
We should focus on cleaning-up our act. Nature will take care of the planet over time. I think I can say that hurricanes and large storms are probably the largest carbon capture mechanism. This is how the planet handles the problem. So, yeah, places like Florida might need to adapt to more intense weather for the next few hundred years. That's just an unavoidable fact as far as I am concerned and until proven otherwise.
There are realities that are inconvenient and nobody wants to discuss. Current example: The effect of the fires in Australia.
https://apnews.com/article/wild-fires-australia-victoria-d3f...
So far, 55K hectares burned and no stop in sight. At 130 tons of CO2 per hectare, that's over seven million tons. Passenger cars in the entire US produce approximately 370 million tons PER YEAR. In other words, in just a few days, a single fire in Australia generated approximately 2% of the CO2 produced by vehicles in the US during an entire year. There are thousands of massive fires around the world, including mine fires that have been burning for hundreds of years. Which means that this idea of achieving net zero or capturing enough CO2 from the atmosphere through technical means is, well, simply not reasonable. As I like to put it, even if all of humanity left this planet it would still take 50K to 100K years for a 100 ppm drop in CO2...because this isn't a lab experiment, it's a planet-scale problem.
We’re probably going to have to do it anyway as a Hail Mary, since we’re now seeing clouds disappear due to warming. But it’s an emergency measure and not a solution. https://www.science.org/content/article/earth-s-clouds-are-s...
The difference between the two is negligible compared to the difference between either of them and what we currently have, which is "unprecedented" on human timescales and euphemistically "radical" on evolutionary ones.
You might as well say "look I just don't understand why people say we need to stop the car, obviously slowing down to walking speed would be enough" while the car continues to accelerate at full throttle towards a cliff edge.
That's what is meant by "stable". It doesn't mean static.
