News
Welcome to the News community!
Rules:
1. Be civil
Attack the argument, not the person. No racism/sexism/bigotry. Good faith argumentation only. This includes accusing another user of being a bot or paid actor. Trolling is uncivil and is grounds for removal and/or a community ban. Do not respond to rule-breaking content; report it and move on.
2. All posts should contain a source (url) that is as reliable and unbiased as possible and must only contain one link.
Obvious right or left wing sources will be removed at the mods discretion. We have an actively updated blocklist, which you can see here: https://lemmy.world/post/2246130 if you feel like any website is missing, contact the mods. Supporting links can be added in comments or posted seperately but not to the post body.
3. No bots, spam or self-promotion.
Only approved bots, which follow the guidelines for bots set by the instance, are allowed.
4. Post titles should be the same as the article used as source.
Posts which titles don’t match the source won’t be removed, but the autoMod will notify you, and if your title misrepresents the original article, the post will be deleted. If the site changed their headline, the bot might still contact you, just ignore it, we won’t delete your post.
5. Only recent news is allowed.
Posts must be news from the most recent 30 days.
6. All posts must be news articles.
No opinion pieces, Listicles, editorials or celebrity gossip is allowed. All posts will be judged on a case-by-case basis.
7. No duplicate posts.
If a source you used was already posted by someone else, the autoMod will leave a message. Please remove your post if the autoMod is correct. If the post that matches your post is very old, we refer you to rule 5.
8. Misinformation is prohibited.
Misinformation / propaganda is strictly prohibited. Any comment or post containing or linking to misinformation will be removed. If you feel that your post has been removed in error, credible sources must be provided.
9. No link shorteners.
The auto mod will contact you if a link shortener is detected, please delete your post if they are right.
10. Don't copy entire article in your post body
For copyright reasons, you are not allowed to copy an entire article into your post body. This is an instance wide rule, that is strictly enforced in this community.
view the rest of the comments
You don't recall correctly: The efficiency of Hydrogen, from solar cell to the wheels is 26%. Electrolysis is highly inefficient and compression and chilling of hydrogen is very energy intensive. Meanwhile, EVs are at 70%.
You are right that batteries kinda suck due to their energy density. However with EVs you can buy today you can still commute every day without noticing any major difference to an ICE car. You can also do long road trips, even in a small car, albeit slower. (Source: did both)
I see I get to have this conversation several times.
I looked it up, hydrogen fuel cells can attain about 60% efficiency from the energy potential in hydrogen, when converting to electricity. So I'm not wrong, we're talking about different numbers.
You're referring to the efficiency of the whole system from generation (via solar panels) to conversion to hydrogen (I assume by electrolysis?) to conversion back to electricity by fuel cell (~50-60% efficiency), then any losses getting the electricity to the wheels. That's a very different number than what I was saying.
AFAIK, no real progress has gone into electrolysis for decades. But we can usually also do natural gas reclamation, which is the process of removing the carbon from CH4, and producing pure hydrogen, which, I believe is a much more energy efficient process.
It becomes an entire discussion to figure out how you're producing hydrogen for the system, which is not an easy topic to tackle in a limited written medium like this one. I decided to forego that and focus on the efficiency of the hydrogen fuel cell vs the energy potential in hydrogen directly. I was still off, I'll give you that, but not so far off to make ICE look like a good option compared to FCVs.
BEVs are great short trip vehicles, daily commuters and all around daily driver vehicles. Even with current battery technology, I'm not disputing that. The fact is that the batteries will cause the cars life to end long before anything else wears out that could potentially cause the car to get scrapped. It's cycle life which is the primary issue, but if we get super long cycle life at the cost of energy density, we generally won't switch (see LiFePO4). If the c rate is too low (significantly lower than current tech), then acceleration and charging time will suffer, and we will equally reject the technology as viable for the purpose. So it needs to beat out lithium/cobalt on cycle life, but come close to, or do the same or better than lithium/cobalt in terms of C rate and energy density.
If anyone finds something that is identical to lithium/cobalt for energy density, and C rate, and just has an improved cycle life while all other factors are the same.... Then IMO the entire industry would pivot so fast your head will spin.
Cycle life is the core of the battery problem. Other factors are nice, but the cycle life is where we need to improve before we can really get rolling on EVs. If that problem can be solved, I don't think that ICE cars will even be built anymore. It will end the consumer petrol market within a decade of such a breakthrough. Of course, there's more uses for gasoline and diesel than vehicles so there will still be gas stations, but there will be a LOT fewer of them, and many will likely be replaced by EV charging points.
If you are looking at the pure engine efficiency, we are now looking at >97% for most EV motors (class IE4). However, the point of the entire transition away from fossil fuels is preventing or delaying climate collapse. For this purpose lowering emissions and reducing energy use go hand in hand, hence the overall efficiency is critical.
Hydrogen is less strongly bound to Carbon than Oxygen, however in this process we produce more CO2 again.
There is a theoretical upper bound for the efficency of water electrolysis, depending on the temperature. While current electrolyzers can surely be improved, since we are already making electricity, we might as well use it directly. Some applications (aircraft, rockets, ...) need the higher energy density of chemical fuels. But: Working with liquid or gaseous hydrogen is terrible: Cyrogenic liquids are not easy to handle, let alone store. Hydrogen will embrittle any metal exposed to it and when inadvertenly mixed with air forms a highly explosive gas. Even the rocket people try to avoid using hydrogen unless they really need the ISP.
So far we have seen EV batteries not degrade a lot due to good BMS. For most cars the battery will last at least 10 years before performance is seriously impacted and even then the battery can be reused for storage (home or grid scale). Most EVs have >40kWh batteries, homes usually need 5-10kWh storage. So one chewed up EV battery could be reused for multiple stationary battery systems.
I do agree that current battery tech is... not great. Having less spicy cells that are easier to recycle or recondition would be a massive gain and more research needs to be a core focus. However Li-Ion and LiFePo are already good enough to work for most people most of the time. Pair this with a lot of wind and solar energy generation and you have mostly sustainable traffic. This can be done right now and it has to be done right now. I argue a lot against hydrogen because it seems like a technology that is not there yet and allows many old players in the energy market to delay a transition which is not beneficial to them.
The argument for hydrogen generally revolves around the fact that it's only waste product is literally H2O. So by using an FCV, you only really emit water as a byproduct, which in general is not of a global cooling chemical than a global warming chemical; though, I don't mean to suggest, in any way, shape, or form that FCVs have any impact at all in reversing global warming.
I would argue that efficiency isn't necessarily the most critical point in regards to "Green" technology. It's an important factor, true, especially when dealing with portable or vehicular energy, since storing a large amount of fuel/energy/power to do a task is generally considered to be a bad idea, mainly due to the size and weight of such storage. I would argue that the efficiency in a less size/weight constrained system, such as a depot or facility, is less of a problem. For example, let's say we're getting 30+ % efficiency solar panels and generating... say, 10kW from the array on average for 5 hours, a total of 50kWh. There's already losses from the solar, but we'll discount that since there's no competing technology to generate power from sunlight which has anywhere near as much efficiency.
From there, we lose maybe 30% from water electrolysis to generate hydrogen. We will lose an additional 40% when that is converted back to electricity for use in FCVs.
The output power will be ~21 kWh.
This is equivalent to a solar array of ~4.5 kW in the same situation, using BEV.
My argument here, against the efficiency matter is: the BEV array is approximately half as large or using panels that are half as efficient, this is going to be located at a facility or location where the hydrogen is stored, which will likely have room for a larger solar array than 10kW. So the only sacrifice made in the scenario is to allocate a larger space and some additional panels to a static location where the hydrolysis is being performed.... Big deal. It's entirely green energy with immense storage capacity (even just as a pressurized gas), and incredible energy density.
Obviously there are still risks with it being literally an explosive, though it can be argued that gasoline also carries that risk and it's literally everywhere. Albeit not as extreme of a risk, but bluntly, gasoline sticks around. Hydrogen generally screws off. Once it's released into atmosphere, yes it's incredibly dangerous and explosive in the presence of oxygen, but it will quickly rise and clear out from ground level where all the spark hazards are... While gasoline releases vapor continually and any ignition of the vaporized gasoline will likely find it's way back to the source of those vapors and ignite them. Hydrogen is a flash and it's gone. It's a trade off of risks either way.
I hear what you're saying, I just don't necessarily agree that it's as bad as it would initially seem.
In the other hand, I've seen the dumb shit people do with anything flammable or explosive and I'd rather not put something so energetic into the hands of the general public. So there's that as well.
I also want to address the matter of urgency. It's not critical that we convert all of the cars to EVs. Personally owned vehicle emissions are not the greenhouse gasses that cause the most significant problem. What most graphs show are intra-country emissions, which either lump all "transportation" emissions into one category, or categorize mostly land-based transport methods. In more global charts they generalize "transportation" as one thing, not defining what each transportation type is contributing. There's a few graphs that are out there, if you dig for them, which show that global transportation is ~75% of emissions, but break it down by purpose/type of transit, and if you really dig into the data, personally owned vehicles are something less than 10% of overall emissions. The rest goes to shipping, like boats, transport planes, trucks etc. large tank liners or cargo vessels are a huge portion of the emissions. There has been zero push to have those converted to electrical options. Whether fuel cell or battery, it's not something that's even discussed. The fact is, those boats are running basically 24/7, consuming more fuel daily than even a mid-sized town of consumer vehicles, and homes combined. And that's just one ship. There are hundreds of them on the water. So having the public convert to EVs, is a literal drop in the bucket of CO2 emissions.
So the question is, why aren't we talking about it? I think the answer is clear. Ships are the bread and butter for oil conglomerates. They need fuel, usually diesel, to get anything anywhere. The global demand for energy to simply move shit around is massive. Nobody wants you looking at it and complaining. Even if the consumer vehicles were all converted to some form of EV overnight, oil companies would still make money hand over fist.
None of this should be taken as "fuck it, let's just keep going with ICE cars". Absofuckinglutely not. Consumers still need to convert to EVs. There is no "but what about" going on here. But having perspective on the issue is essential. We all need to do our part. Right now, everyone seems happy to stay focused on consumer vehicles and the drive towards personal responsibility of carbon emissions, but that's only focusing on consumer emissions. Industrial emissions from shipping and energy production, even just getting the energy products to where they need to go, should also be something that is a part of the discussion because they are far and above more egregious in their carbon footprint than the consumers are. IMO, they've set the pubic against itself to distract from the fact that we're not the biggest problem. There's now a war of sorts happening between "tree hugging" EV advocates and "dinosaur burning" ICE enthusiasts. It's worked and we need to realise that we are all on the same side, and we need to recognize that the real problem isn't us, it's the companies who would rather ruin the planet than ruin their bottom line. Yes, that includes oil companies, but also shipping companies. Other industries are also guilty of massive ecological destruction too.
IMO, this is yet another example of the "elite" driving a narrative that benefits them. That somehow because reasons we should all feel bad about driving our cars to the places we need to go, burning mere gallons of fuel daily for everything we do, while they burn barrels of fuel hourly so they can line their pockets with our money.
Personally, I don't think we should give up on fuel cells or green hydrogen, because there's literal acres of land that can be used for solar to generate the power to produce hydrogen, and use that hydrogen to power fuel cell based electric vessels for transport. They have a virtually inexhaustible supply of water right next to where these docks exist, and plenty of land for solar which can be used for the process. It makes sense; and with a fuel cell vessel the hydrogen can be stored in large pressurized containers that are regularly tested and validated to be safe, with extended safety mechanisms in place that we basically can't do with consumer goods. Weight is also less of a concern, and they already allocate a nontrivial amount of space on the ship to storing fuel for the journey. It would make such a significant impact to overall emissions that the consumer EV thing would be little more than a footnote, rather than the headline news it is right now.
But I don't see anyone even remotely discussing it. Maybe they should.