CapeWearingAeroplane @ CapeWearingAeroplane @sopuli.xyz

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A couple issues have been mentioned, but what hasn't been mentioned is that hydrogen is difficult to store, because the molecules are small enough do migrate through most containers and escape. If your container is made of metal, you also get something called hydrogen embrittlement which breaks your container over time.

The thing with trains is twofold: First of all, it's relatively easy to ensure that a train is more or less always hooked up to the grid (lines over the tracks). That means it can charge almost constantly, and doesn't need a large battery.

The second thing is that the energy required to run a train scales very slowly with mass, because there is almost no rolling resistance (steel wheels on steel tracks have that advantage). That means you can increase the base weight of the train a bit without worrying about increased energy consumption.

Hydrogen can compete in applications where you need large amounts of energy, that needs to be transported, and where you don't have regular access to the grid. Prime examples could be long-distance shipping, flight, and long-distance trucking through areas with little or no electric infrastructure (e.g. rural Australia).

Hydrogen storage is definitely something we need to do more research on. Cooling as well turns out to be quite a bit more complex than for most other fluids because of the quantum effects that become relevant once you close in on the critical temperature (which is very relevant if you want to store liquid hydrogen). It's not only a problem that hydrogen escapes when diffusing through a container, but it usually degrades the material the container is made of in the process, reducing the life time of the containers.

We're currently looking into using various materials that can adsorb and desorb hydrogen in a controlled manner for large scale storage applications, that's one of the possible solutions to the fact that hydrogen can diffuse through pretty much anything.

Let's not be one-sided here: Guns Germs and Steel, like most other works, has shortcomings, but I think it is more fair to say that it has caused a lot of discussion. A long list of experts, as late as this year, back up the book to varying degrees.

Even if you choose to discredit the book, I'm making the argument that Japan had a lot of resources that made hunter-gatherer societies viable enough that they actually formed year-round settlements. That's a claim I have yet to see someone dispute, as there is a bunch of archeological evidence backing it up.

I've found ChatGPT is good for small tasks that require me to code in languages I don't use often and don't know well. My prime examples are writing CMakeLists.txt files, and generating regex patterns.

Also, if I want to write a quick little bash script to do something, it's much better at remembering syntax and string handling tricks than me.

It's very common to have limitations to freedom of speech. The most common ones I can think of right now are

• Threats of violence
• Other serious threats
• Inciting rebellion
• Inciting terrorism
• "Hate speech" (usually via one of the above)
• Sharing classified information

At what point do people start rising up against these cartels? I've seen a video of some guys being scared shitless when they were stopped by armed civilians on some rural road in South America, only to be told that they were locals who were out to stop the cartels from robbing people on the road. I wonder when it gets to the point where that is a common occurrence?

In a lot of parliamentary systems still have very effective splitting into three branches. Thats because when you have an effective multi-party system, the government often consists of the "largest minority" coalition in the parliament. For example: After an election, the parliament consists of

• 10 % A
• 25 % B
• 25 % C
• 15 % D
• 20 % E
• 5 % F

They get together and discuss who will form a government. A, B, and F agree on enough topics to form a government together, but only have 40 % of the votes. Unless some other coalition, with a larger number of votes, forms, the government will consist of A, B, and F.

Now comes the fun part: A, B and F are at the mercy of the parliament. If they pull some stuff that makes parliament mad enough, C, D and E might put aside their differences, vote out the government and form a new government, so the government has to compromise with e.g. D, to get enough votes to stay in power. This can give small parties a large amount of swing power.

Also: Once A, B and F are in government together, they agree on a platform. That means that even though B is the largest party in government, they have to give in to some requirements from F. This effectively means that the government functions as its own body, enacting the agreed upon political platform of A, B and F.

Because they have pre-agreed-upon compromises, A, B, and F effectively enhance their power in parliament. Even if a representative from A disagrees with some policy the government is trying to pass, they will likely vote for it, because they know that at a later stage, B and F will vote for some policy that they propose. However, if the government goes too far, a party in parliament might decide to pull support, and leave the government they are a part of, effecting a change of government.

This system also incentivises wide compromises and stability. If, after some later election, the government consists of A, D and E, they are unlikely to undo a lot of the work by the previous government, because A will oppose that.

Definitely! We have to do pretty much everything we can to prevent the world from burning and drowning simultaneously.

On that note - I should probably get back to work ;)

I see your points, and largely agree with them. I don't think we're going to convince each other here, and thats because we put very different weight on the question

"What if we end up needing it, but haven't built it?"

To me, that is the deciding question, which makes me argue that we should invest in it, while for you it seems the answer is that we should invest in such a way that we minimise the probability of needing it in the first place, which I think is a fair answer.

I can't include emissions for building infrastructure or natural gas leaks, but I think it's a fair assumption that those costs are the same order of magnitude whether you use the gas directly or convert it to hydrogen + CO2, and then use the hydrogen. I mention transportation a bit further down.

Someone do the math on the net CO2 impact between jet fuel and natural gas reforming

Ask and thou shalt receive.

When we burn hydrocarbons, the overall reaction going on (neglecting byproducts) is

2 C_nH_{2n + 2} + (3n + 1) O₂ => 2nCO₂ + (2n + 2)H₂O

When we steam-reform hydrocarbons, we use the reaction

4n H₂O + 2 C_nH_2n+2 => 2 nCO₂ + 2 (3n + 1)H₂

Such that the CO₂ emissions from the consumption of the hydrocarbons is exactly equal. Now, the question is about efficiency. Steam reforming has an efficiency of about 65-75 %, which means we need (very roughly) 253 kJ of energy as input per mol steam-reformed hydrocarbon (assuming 65 % efficiency).

The (ideal) energy output from the corresponding consumption of 4 moles of hydrogen is approximately 1140 kJ. Hydrogen fuel cells typically have an efficiency of about 40-60%, so the true output is about 456 kJ (assuming efficiency of 40 %). This gives a net energy output of 203 kJ per mole gas consumed by steam reforming, and consecutive hydrogen consumption.

For comparison: Internal combustion engines typically have efficiencies around 20-35%. If the same gas is consumed in a gas turbine, we thus get an energy output of about 280 kJ (assuming efficiency of 35%).

The comparison in total:

• Assuming lower end efficiencies for steam reforming + fuel cell: 203 kJ / mol gas
• Assuming higher end efficiencies for steam reforming + fuel cell: 464 kJ / mol gas
• Assuming lower end efficiency for gas turbine: 160 kJ / mol gas
• Assuming higher end efficiency for gas turbine: 280 kJ / mol gas

So, the only case in which the gas turbine beats steam reforming + hydrogen on efficiency is when we assume higher-end efficiency for gas turbines, and lower-end efficiencies for steam reforming and fuel cells.

It should also be added that combustion engines have a theoretical maximum efficiency of about 58 %, while hydrogen fuel cells have a theoretical maximum close to 100 %. In addition, combustion engines have a huge head start on fuel cells regarding development. We can expect steam-reforming + fuel cells to improve a lot in efficiency the coming years, the same is not the case for combustion.

I have also not mentioned yet that hydrogen has a higher energy density (by mass) than gas, making the transportation cost and emissions (per joule transported fuel) lower.

Shortly speaking: The numbers say that steam-reforming + fuel cells is already a competitive option when looking at energy waste and emissions per joule produced. It can be expected to get even better in coming years.

Now for some more points I haven't mentioned yet:

Using steam-reformed hydrogen makes hydrogen cheap, which helps incentivise building things that use hydrogen, rather than combustion, which further increases demand for hydrogen. This helps lay the ground work for future, green, hydrogen infrastructure.

Maybe most importantly of all: When hydrogen is produced by steam reforming, all the CO₂ is produced in one place, which can make CO₂-capture viable. When the gas is burned as fuel in a bunch of different places, CO₂-capture becomes less viable, as current technology heavily favours large, centralised capture operations.

I definitely think hydrogen and batteries solve different problems, and we're going to need both. Batteries have lower energy waste when recharging, and can handle power fluctuations better, while hydrogen has a far higher energy density, and scales much better to large scale storage. In addition, hydrogen tanks don't wear out the same way as batteries after many empty-full cycles.

This makes hydrogen very good for large scale applications, where the power requirements don't fluctuate much.

If the large governmental investments go into renewables and storage we have more energy faster.

I'm not actually sure this is true in the long run. Yes, we will have more energy in 10 years, but will we have more in 30, 40, 50 years? When you look at the capacity of reactors built in e.g. France in (I think) the 70's-80's, it's clear that once you have reactor designs up and running, building a lot of capacity both cheaper and quicker. The first reactors are both most expensive, and take the longest to build.

And that's the exact point I'm trying to make: Not that we should only build nuclear, but that if we want to minimise the risk of future energy shortages, we should spread our eggs among as many baskets as possible. We can't just plan for 10-15 years ahead, we have to plan for 40-50 years ahead. On that time-scale, it is hard or impossible to say whether we will need nuclear. Therefore, it would be foolish to not invest in building and maintaining the institutional knowledge that comes with building reactors.

Even 20 years from now it is hard to say what our needs will be. Building reactors now ensures that we have some massive energy sources coming online in 20 years, if we in 15 years see that we have enough, we can scale down on other sources, but I think that is highly unlikely: We will always find a way to use excess energy for something useful.

Something something pls give upvotes

Yes and no: the resources that made Japan very viable for hunter-gatherer societies are very different from the resources that make an area viable for agricultural societies.

Whereas agricultural societies value open areas and metal ore a lot, the jomon societies lived primarily off foraging and hunting in wooded areas. With the rise of agriculture, those areas largely disappeared, to the point where Japan was almost deforested.

Seafood is also something Japan had a huge abundance of, but like most of the world, they overfished their stocks.

For the "no" part: Resources like metal ore, coal, oil, waterfalls for hydropower, etc. do not make a hunter-gatherer society less viable, but can serve to make an already highly technologically developed society even more viable. The point being that although Japan had an abundance of resources making hunter-gatherer lifestyles much more viable than in most of the world, they can still lack in resources that are valuable to Iron Age and later societies.

The result is that

1: It took longer for agriculture to become a viable competitor against hunting/gathering in Japan.

2: Once agriculture was adopted, the resources in demand were not in high supply (as they weren't there in there in the first place).

Yes: 300 BC is about 2500 years ago, which is roughly when the Jomon period ended.

My point was that the reason agriculture had not spread to japan yet wasn't because they weren't aware of it, but because Japan was so resource rich that it wasn't able to compete as a lifestyle.

It's well documented that the jomon culture traded with Korean farmers for centuries or even millennia before adopting agriculture themselves. This is an important reason for why they weren't wiped out by disease when they came into contact with agricultural societies. Historical evidence also suggests that they were better fed than their agricultural neighbours in Korea and northern China in that period.

In short: The reason Japan started developing e.g. metalworking much later than their neighbours wasn't a lack of resources, but an abundance of them. Which led them to not adopt agriculture before neighbouring societies had developed it sufficiently far to become competitive. Technology and social stratification typically follow once agriculture is adopted.

Thinking of the same thing, but if I delete my account on an instance, do the comments and posts from that account also get deleted?

Money is a finite resource as of now

Most renewable energy projects are not larger than that private entities can invest and build them, as they are assumed to be profitable. Nuclear requires large, governmental investments. Both can be funded if we push the private sector by squeezing out fossil fuels with regulation and forcing them to invest in renewables.

If (...) we continue to need even more energy we can hopefully start with fusion in 20 years.

The problem with starting with fusion in 20 years is twofold:

1: It assumes we will have viable, large scale fusion reactors developed within 20 years. Thats a big if.

2: If we start in 20 years, we won't have them until 30-40 years from now.

Thats why we have to start planning now for exactly the case you are talking about: A situation 20 years from now when we have transitioned mostly to renewables, but still need more energy. That is a very likely future, which is why we need to build nuclear now, so that we have it in 20 years, when we will need it.

If memory serves me right, I'm talking about the Jomon period, which is the periode from about 10 000 years ago, up until about 2500 years ago, when the Yayoi period started. I believe the start of the Yayoi period is marked (among other things) by the spread of agriculture throughout Japan.

Hello from sopuli.xyz! We are officially interacting:)