The "nearly 100%" is in comparison to regular electrolysis.

From the abstract of the paper:

>[...]and similar performance to a typical PEM electrolyser operating in high-purity water.

The BS claim in the article is being used to push this research on social media. I don't know how many times I've come across this "news" in the last few weeks.

It's misleading. The "100%" being pushed here are in regards to regular electrolysis. They have basically come up with a less efficient way to split water.

Claims being made in the article are misleading and the research itself - which is actively being pushed on mutliple social media channels in a way that borders on the absurd - is massively overstated.

>“We have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency

No, that's a BS claim. The process is not "nearly 100%" efficient. What they have actually done is that they achieved nearly the same efficiency as with conventional electrolysis using standard catalysts and pure water.

As per the abstract from the actual paper: >[...]and similar performance to a typical PEM electrolyser operating in high-purity water.

This whole thing - i.e. "we need to solve seawater electrolysis to make the hydrogen economy happen" is absolute BS, for the simple reason that the problem doesn't actually exist, because conventional electrolysis coupled with reverse osmosis (SWRO) is basically as efficient as it gets:

>Our analysis reveals there are limited economic and environmental incentives of pursuing R&D on today's nascent direct seawater electrolysis technology. As commercial water electrolysis requires a significant amount of energy compared to SWRO, the capital and operating costs of SWRO are found to be negligible. This leads to an insignificant increase in levelized cost of H2 (<0.1 $ per kg H2) and CO2 emissions (<0.1%) from a SWRO-PEM coupled process.

>https://pubs.rsc.org/en/content/articlelanding/2021/ee/d1ee00870f

"Direct electrolysis" results in insignificant gains. Purifying seawater is not what makes the process inefficient and not having to purify the water doesn't make it markedly more efficient let alone cost saving.

What's "preventing the hydrogen economy from happening" is not that we have to deal with seawater - it's that electrolysis itself takes massive amounts of energy and isn't efficient. You don't improve the underlying economic obstacles by slashing less then 10 cents from the price of a kg of hydrogen.

The "obstalce" is not seawater, it's the inefficiency of electrolysis. And the people pushing this research just told you that somebody has come with a way that's less efficient than regular electrolysis.

>Recent studies show that a global transition to 100% renewable energy across all sectors – power, heat, transport and desalination well before 2050 is feasible.[5][6][7][8] According to a review of the 181 peer-reviewed papers on 100% renewable energy that were published until 2018, "[t]he great majority of all publications highlights the technical feasibility and economic viability of 100% RE systems."[9] A review of 97 papers published since 2004 and focusing on islands concluded that across the studies 100% renewable energy was found to be "technically feasible and economically viable."[12] A 2022 review found that the main conclusion of most of the literature in the field is that 100% renewables is feasible worldwide at low cost.[13]

>Existing technologies, including storage, are capable of generating a secure energy supply at every hour throughout the year. The sustainable energy system is more efficient and cost effective than the existing system.[14] The United Nations Intergovernmental Panel on Climate Change (IPCC) stated in their 2011 report that there is little that limits integrating renewable technologies for satisfying the total global energy demand.

https://en.wikipedia.org/wiki/100%25_renewable_energy

In all seriousness though, maybe it's time to accept expert oppinion on that matter.

Expert opinion being that nuclear is too slow, too costly and simply not scalable enough, while going 100% renewable is not only feasible but likely also cheaper.

https://phys.org/news/2011-05-nuclear-power-world-energy.html

https://www.reuters.com/article/us-energy-nuclearpower-idUSKBN1W909J

https://spectator.clingendael.org/en/publication/nuclear-energy-too-costly-and-too-late

By all means, keep regurgitating misinfo pushed by conservative think tanks to funnel even more subsidies into nuclear and fossil fuels.

>We could have been 100% nuclear decades ago but it was the greens who shut down building of all new nuclear plants.

That's pure misinformation.

https://phys.org/news/2011-05-nuclear-power-world-energy.html

Nuclear basically isn't scalable beyond 1 TW globally. Geothermal energy alone has twice that potential. Nuclear is pretty much a dead end as far terrestial utility-scale use is concerned.

Blaming "[political group you don't like]" for the issues inherent to the technology isn't going to solve anything.

>You basically need to invent a global conspiracy for that to make sense.

The consensus in those circles seems to be that environmental groups/"the greens"/[party or group of choice you don't like] where all funded by the fossil fuel industry and the Soviet Union Russia to make nuclear look bad. I shit you not that what's I've seen people arguing on this subreddit.

no bro nuclear would totally be economic and viable if we would just poured more funds into it. Trust me bro, the key to making nuclear finally work is to build smaller and less efficient plants.

Like, have you actually looked at the subsidies nuclear has received? Granted this is nearly a decade old, but it's not like the situation has changed all that much:

https://www.ucsusa.org/resources/nuclear-power-still-not-viable-without-subsidies#ucs-report-downloads

It's not like we haven't already established that 100% renewables is viable:

>Recent studies show that a global transition to 100% renewable energy across all sectors – power, heat, transport and desalination well before 2050 is feasible. According to a review of the 181 peer-reviewed papers on 100% renewable energy that were published until 2018, "[t]he great majority of all publications highlights the technical feasibility and economic viability of 100% RE systems." A review of 97 papers published since 2004 and focusing on islands concluded that across the studies 100% renewable energy was found to be "technically feasible and economically viable." A 2022 review found that the main conclusion of most of the literature in the field is that 100% renewables is feasible worldwide at low cost.

>Existing technologies, including storage, are capable of generating a secure energy supply at every hour throughout the year. The sustainable energy system is more efficient and cost effective than the existing system. The United Nations Intergovernmental Panel on Climate Change (IPCC) stated in their 2011 report that there is little that limits integrating renewable technologies for satisfying the total global energy demand.

https://en.wikipedia.org/wiki/100%25_renewable_energy

The IPCC pointed this out over a decade ago.

The concept of "space fighters" makes little to no actual sense:

http://projectrho.com/public_html/rocket/fighter.php

https://futurewarstories.blogspot.com/2012/05/fws-topics-hard-science-space-fighters.html

Ah yes. Like with the space shuttle which famously lacked any kind of control surfaces.

The benefits from this are neglegible small. The problem is not purefication of seawater, the problem is the staggering amount of energy needed for electrolysis. Seawater reverse osmosis (SWRO) takes basically no energy compared to splitting water into hydrogen and oxygen.

>As commercial water electrolysis requires a significant amount of energy compared to SWRO, the capital and operating costs of SWRO are found to be negligible. This leads to an insignificant increase in levelized cost of H2 (<0.1 $ per kg H2) and CO2 emissions (<0.1%) from a SWRO-PEM coupled process.

https://pubs.rsc.org/en/content/articlelanding/2021/ee/d1ee00870f

How does this relate to "futurology"? This is basically a veiled ad for a producer of storage tanks, nothing more.

>Rather than disposing of batteries after two or three years

Interesting to frame it this way, given that most phones nowadays don't even feature easily replaceable batteries.

People don't "dispose of batteries". If anything they dispose entire phones. Not to mention that most "phone batteries" I have come across actually last a lot longer than two or three years to begin with.

>Only 10% of used handheld batteries, including for mobile phones, are collected for recycling in Australia, which is low by international standards. The remaining 90% of batteries go to landfill or are disposed of incorrectly, which causes considerable damage to the environment.

>The high cost of recycling lithium and other materials from batteries is a major barrier to these items being reused, but the team’s innovation could help to address this challenge.

They don't actually adress the issue they are complaining about here, which is "handheld batteries" not being collected for recycling. How is introducing yet another "revolutionary" battery technology going to prevent phones ending up in landfills becasue people dispose of them incorrectly?

Answer: It won't.

What a strange article.

Unless you want to build an actual death ray, the footprint of the receiving array on he ground is comparable to simply building a terrestial solar array.

Could you power equipment this way? Sure. Does it make any actual sense, given the inherent downsides and massive additional costs?

No.

I pointed this out when the first "stories" about White paper (get it?) were linked to in this sub. This is really more of a mathematical artifact than anything else. But people on this sub were adamant that this was, in fact, a demonstration of actual warp effects.

Despite the fact that nothing physical was even demonstrated.

None of these address the inherent problems the technology has and which the aricle brings up, and it also directly contradicts the claim that you "could built them out much larger". You still need receiving arrays on the ground which have to be of comparable size to the solar parks you're aiming to replace.

Arguing generation efficiency is pointless, as the ratio is pretty much fixed and improving efficiency further will impact both space and terrestial arrays. The point is transmission and conversion efficiency, which is where the technology fails, because of the massive losses.

"Networking plants in orbit" will only exacerbate transmission losses and does not change the inherent limitations placed upon receiving arrays.

I don't even know what the last point is supposed to mean. Are you under the impression that we currently share power the same way we "share" internet connections? That Africa's powergrid is connected to the Americas'?

You can not feasibly eliminate any existing infrastructure with this. Ground based grids will always be more efficient than "beaming" anything. Geostationary orbit is 35000 km up.

Putting things "in space" doesn't magically solve problems, regardless of how cool it sounds. In this case it has more downsides and creates more problems than it actually "solves", not to mention making critical infrastructure exemely hard to maintain or replace. If anything it might make more sense to simply reflect sunlight. That way you at least don't end up with a completly useless groundstation if something on your space array breaks down.

>It'll take time for the tech to become viable of course, but as costs for getting material into space continue to become cheaper and cheaper over time, I see no reason that this couldn't become real one day.

Plenty of reasons, basic physics for one. Nor will launch costs continue to drop to a level to make this viable, at least not with chemical rocket technology alone (and no, "spin launch" isn't what I am referring to).

>It's very cool and has such a sci-fi vibe to it.

Which the only reason this crops up again every few decades. This is not about "the tech becoming viable". Unless you want to sent a literal death ray into orbit the math simply doesn't add up (on the other, the math does add up for the involved companies as far as money is concerned).

Seeing how these are basically the saim claims regarding solar power as in the other recently posted articles...

>The concept of harvesting solar energy in space is not a new one, but until now, high launch costs and limited technology have hampered progress

High launch costs still hamper the idea. NASA concluded in a 1999 study that to even be competetive launch costs would have to come down to $200-$300/kg to GEO. That is not going to happen for a very long time, and probably not with purely chemical launch systems either. The "limited technology" argument applies to both space and terrestial arrays - only that gains in efficiency and manufdacturing capacity benefit terrestial arrays more, if anything, especially as far as decentralised power generation and storage is concerned.

>a cost modelling analysis by consultancy Frazer-Nash shows that the LCOE (levelised cost of electricity), used to compare different methods of electricity generation on a consistent basis, falls between £37 and £74/MWh, which is competitive with terrestrial renewable technologies, the organisation said.

No it is not. Even assuming the best case here this is still outperformed by utility-scale solar installations. Even wind power can outperform this. I highly doubt that this is competetive on any level if taking into account the difficulty of maintenance alone.

>[...]and with much lower land usage than conventional renewables, is helping the idea gain traction.

Also a false claim. Unless you want to sent a literal death ray in to orbit you still need about as much space on the ground for the receiving array as you would with regular solar installations - only with all the added downsides of doing things "in space":

https://dothemath.ucsd.edu/2012/03/space-based-solar-power/

>A space-based solar power system might sound very cool and futuristic, and it may seem at first blush an obvious answer to intermittency, but this comes at a big cost. Among the possibly unanticipated challenges:

>* The gain over the a good location on the ground is only a factor of 3 (2.4× in summer, 4.2× in winter at 35° latitude).

• It’s almost as hard to get energy back to the ground as it is to get the equipment into space in the first place.
• The microwave link faces problems with transmission through the atmosphere, and also flirts with roasting ducks on the wing.
• Diffraction of the downlink beam, together with energy density limits, means that very large areas of the ground still need to be dedicated to energy collection.

>Traditional solar photovoltaics in good locations can accomplish much the same for much reduced cost, and with only a few times more land than the microwave link approach would demand. The installations will be serviceable and will last longer. Batteries seem an easier way to cover storage shortcomings than launching stuff to space. I did not even address solar thermal schemes in this post, which competes well with photovoltaics and can very naturally build in storage capability.

>I am left puzzled as to why we would want to take a harder, more expensive road to solar power. I think it is just not intuitive to most how difficult and expensive space is. **And perhaps they think it’s very futuristic and cool to push our power generation out to space: it fits the preferred narrative about where we’re going. I don’t know—I’m just guessing.

>Astronomers frequently face this issue: should we build a telescope/observatory on the ground, or launch something into space? The prevailing wisdom is that if the science can be accomplished on the ground, then by golly you’d best do it that way. You’ll have the result sooner, at less expense, and with a greater chance of success.

I am not certain this would even have realistic use cases for military applications, outside of actual space-based weapon systems (the afromentioned death ray).

The math simply doesn't add up, even if you assume unrealistic optimal conditions. Looking at the involved companies it's quite clear that these are bascially hand-outs to the industry. "Space base dsolar power" isn't any more "feasible" than it has been in the decades since the idea was first envisioned, simply because the underlaying physics don't change. Either you build a death-ray in orbit or it's more attractive and straight-forward to simply build collecting arrays on earth.

>that it's not that much of an issue anymore.

It actually still is a big issue though. And solar panels getting cheaper favors decentralised installation on the ground, if anything.

Unless you want to sent a literal death ray in to orbit you still need about as much space on the ground for the receiving array as you would with regular solar installations - only with all the added downsides of doing things "in space":

https://dothemath.ucsd.edu/2012/03/space-based-solar-power/

>A space-based solar power system might sound very cool and futuristic, and it may seem at first blush an obvious answer to intermittency, but this comes at a big cost. Among the possibly unanticipated challenges:

>* The gain over the a good location on the ground is only a factor of 3 (2.4× in summer, 4.2× in winter at 35° latitude).

• It’s almost as hard to get energy back to the ground as it is to get the equipment into space in the first place.
• The microwave link faces problems with transmission through the atmosphere, and also flirts with roasting ducks on the wing.
• Diffraction of the downlink beam, together with energy density limits, means that very large areas of the ground still need to be dedicated to energy collection.

>Traditional solar photovoltaics in good locations can accomplish much the same for much reduced cost, and with only a few times more land than the microwave link approach would demand. The installations will be serviceable and will last longer. Batteries seem an easier way to cover storage shortcomings than launching stuff to space. I did not even address solar thermal schemes in this post, which competes well with photovoltaics and can very naturally build in storage capability.

>I am left puzzled as to why we would want to take a harder, more expensive road to solar power. I think it is just not intuitive to most how difficult and expensive space is. And perhaps they think it’s very futuristic and cool to push our power generation out to space: it fits the preferred narrative about where we’re going. I don’t know—I’m just guessing.

>Astronomers frequently face this issue: should we build a telescope/observatory on the ground, or launch something into space? The prevailing wisdom is that if the science can be accomplished on the ground, then by golly you’d best do it that way. You’ll have the result sooner, at less expense, and with a greater chance of success.

I am not certain this would even have realistic use cases for military applications, outside of actual space-based weapon systems (the afromentioned death ray).

The math simply doesn't add up, even if you assume unrealistic optimal conditions. Looking at the involved companies it's quite clear that these are bascially hand-outs to the industry.

Ariane worked just fine for James Web, BepiColombo and Rosetta, and Ariane 6 is already slated for multiple interplanetary missions. Reusability lowers launch capacity, it doesn't increase it.

ULA managed to sent two rovers to Mars using Atlas V, and Ariane 6 can carry 3 tons more into GTO than Atlas.

I think ESA is going to manage just fine.

>I'm not going to engage with this.

Nor are you going to engage your other fallacies I take it? Like the actual costs? Or your inane comparison of space exploration with naval travel? Or how Moore's laws is supposed to factor into this at all?

You're simply salty because I'm calling you out on your nonsensical claims.

>that SpaceX/Elon Musk is lying and that the whole industry is out to grift us

How is any of this up to debate, given their claims regarding Starship, Mars colonies, Starlink paying for all of this? "The whole industry" you are imagining here doesn't exist as far "Space [Tourism/Mining/Manufacturing]" is concerned, and those CGI space hotels have been debunked numerous times as attempts to defraud investors becasue they are not feasible on basically every level. This is hardly the first time this has been pointed out on this subreddit.

My man, if you can't back up your claims you have no arguments.

>This figure is wrong. It's closed to 22 tons expended.

I didn't give data for expended, and not expended is 16.7 t to LEO:

https://en.wikipedia.org/wiki/Falcon_9

FT: 22.8 t (50,000 lb)[1] Expended
16.7 t (37,000 lb)[6] when landing on ASDS

Note also that the "price" given on the SpaceX PR material is for non-expended launches, while the "performance" to LEO/GTO is for expendable launches. The $67 million are for 17.6 t to LEO / 5.5 to GTO. What are you criticizing here? BTW, let me know if you have an actual valid source for prices for FT launches, I was unable to find any.

>Further, you're basing your figures on the list price in an industry with little competition. SpaceX doesn't need to cut prices as much as they can because no one can compete on price anyway.

Yet you're basing your claims on an article that only argues based on (inaccurate) prices given by SpaceX. If you have valid sources regarding the actual production, support and launch costs, by all means let's hear them.

>We know roughly how much the stages of the rocket cost, and the cost of refurbishment. If anything, my numbers are conservative.

"Roughly", the same way the article makes inaccurate and false claims based on "rough calculations" and aspirational launch costs?

I honestly doubt that you have any knowledge regarding the actual costs, apart from speculations based on twitter posts and PR-BS. Remind me again when Starship was supposed to be launching people to that CGI Mars colony. Again, if you have actual valid sources, by all means let's hear them.

>That's the spirit! If we followed that logic, The United States wouldn't exist.

Lol, faulty logic. Maybe look up who founded Columbus' ships&trips and for what reason. I don't know why people are still so delusional to compare spaceflight to naval exploration. As far as I can tell it has been pointed out to oblivion why that is gigantic fallacy based on ignorance with a nice sprinkling of dunning-kruger.

There is no reason and no feasible way - and there won't be using purely chemical rockets - to build up a "space mining industry or a space manufacturing industry". Because it's order of magnitudes more costly to do any of this in space than to do it on earth.

Neither is any form of actual "space tourism" realistic apart from ferrying obscenly rich people to small existing stations. The whole notion of "space hotels" is so utterly stupid that I'm have trouble comprehending that people would actually fall for these grifters, apart from a basic lack of knowledge regarding the compelxity of orbital operations. Space tourism isn't simply "like cruise ships, but in space".

You can't just add "space" to stuff and pretend that that's going to be the next big thing because "Space" and Daddy Elon whispering sweets nothings into your ear. If you actually do the math and look at the feasibility you'll notice that not only do none of these space mining and tourism visions to defraud investors add up. You'll also note that instead of funding those Mars colonies, Starlink is literally burning money and desperate for investors.

And again, what does Moore's law have to do with any of this?

>The cost per kilogram to orbit has fallen from about $10,000 in 2000, to roughly $2000 today

Highly misleading, you might want to check the actual launch costs, not the aspirational future costs that the article false claims as fact.

See for example

https://www.cnbc.com/2022/03/23/spacex-raises-prices-for-launches-and-starlink-due-to-inflation.html

A Falcon 9 launch costs ~$67 million and can carry ~17 tons to orbit when the rocket is not expended.

That adds up to about $4000 per kg. If you just need to launch small payloads the costs are even higher:

>The company also adjusted its prices for its small satellite rideshare program. Those flights will now start at $1.1 million to fly a payload weighing 200 kilograms to a sun-synchronous orbit, up from a base price of $1 million. SpaceX increased the cost of additional payload mass by 10% as well and will now charge $5,500 per extra kilogram, up from a previous $5,000 per kilogram.

The costs of spaceflight will not continue to fall much further with conventional chemical rockets, regardless of the idiotic numbers that Musk or SpaceX dream up. Reaching tripple or double digit numbers per kg would require straight-up slave labor and free fuel&propellant.

>There is so much potential, from tourism to advertising, to research and development/manufacturing of products that can only be done in micro-gravity, to eventually resource mining...

No, there isn't, for the simple reason that doing any of this in space is going to be more costly and complicated than doing it on earth. But all of these are ways to defraud investors.

How is "space" even remotely comparable to Moore's law or digital computing and why does Moore's law "slowing down" mean anything in this regard? "Moore's law" is just an observation of trends in transistor density.

>As with traditional wind turbines, size is key.

>On the other hand, they don't create the noise

>and Aeromine places a relatively small, cheap internal propeller (perhaps 36 inches/91 cm in diameter) in that tube to run a generator

>So what are the downsides? Well, these things need to be installed in spots where the wind direction is pretty constant, because they don't angle themselves to catch a breeze – and they probably never will, since they're designed to be such a cost-conscious machine.

So instead of low-frequency noise they create high-frequency noise, they are less efficient than traditional ones, and they don't even work when the wind is coming in from the wrong direction. On top of that they look like oversized rooftop AC units.

If I had a dime for every project pushing the "this is going to work so much better than traditional wind turbines"-angle and promising that no, this time it's going to be different, really bro just trust me, all we need to do is complicate a very simply design to make it more affordable and efficient I would have a lot of dimes. Maybe even some dollars.

I mean, solar panel output might vary by daytime and cloudcover, but it usually doesn't change all that much due to the sun unexpectedly rising in the north. Solar panels also don't need as much maintenance, and there's not a whole lot that can break, apart from the panel itself. And I don't think birds and instects tend to nest in or on solar panels all that much. Below, maybe.

>That's exactly how it works. To use the star was just recently consumed. This is our reality and it is 100% true.

No it's not. We know that what we are observing happened hundreds of millions of years ago and not recently. Hence this event did not happen in October 2018 - we know it didn't, because w eknow that the speed of light remains constant over galactic and intergalactic distances. That we are observing the event just now has no bearing over when it originally happened.

>It's not that the black hole isn't aware of you.

I am reasonably certain that a black hole isn't aware of anything, regardless of reference frame, and that both we and the black hole can indeed exist in the same referance frame.

>In October 2018, a small star was ripped to shreds when it wandered too close to a black hole in a galaxy located 665 million light years away from Earth. Though it may sound thrilling, the event did not come as a surprise to astronomers who occasionally witness these violent incidents while scanning the night sky.

No, it wasn't "ripped to shreds in October 2018". That's not how speed of light works. You can not witness something 665 million light years away in the instant it happens.

The "important" part is at the very end:

>As light passes through these windows, the machine processes the colour as data, explains Ostadabbas. Machine learning models then look for patterns in order to better identify the corresponding colours analysed by the device.

>“Instead of breaking it down into its principal red, green and blue components, when a coloured light appears, say, on a detector, instead of just seeking those components, we are using the entire spectral information,” says Kar.

"Ordinary" cameras sensors (CCD/CMOS) use filters (e.g. Bayer, which also aims to account for the human eye's sensitivity to green light) to reconstruct an image made up of the three primary colours (RGB). The camera sensor does not actually detect "millions" of colours - it just detects varying levels of the colours passed through by the filter.

As I understand the article, this is a different approach that does not restrict the recorded spectrum in the same way.