What is actually the simplest answer why hydrogen is not feasible yet for a replacement of our usual ways to heat buildings or drive cars. I heard that Hydrogen makes sense for larger vehicles that have to drive for a lot of miles but smaller ones are not really in development outside of toyota’s experiments. Is there already a way to when it could get feasible?
In: 475
Hydrogen explodes. Like big. People are justifiably hesitant to put a giant hydrogen bomb into every vehicle on the road and into every home.
hydrogen is explosive in almsot any concentration with air, hydrogen is very hard to store because it leaks out of most things, hydrogen takes up a huge amount of space because you either; need to make it liquid which only happens if you cool it to -253°C, or store it as gas at extreme pressures, which need massively strong tanks
Today there is no large scale carbon-emission free production of hydrogen. So called “green hydrogen”..
There is just “blue hydrogen” which comes ultimately from oil and needs to be coupled with undeveloped or unproven carbon capture methods to be environmentally friendly.
This explains the lack of interest in going down that path from everyone except oil companies.And if they were serious, and not just using the prospect to confuse people, they would do it.
In some places like the Netherlands, to a limited degree it’s already a reality and automotor companies have H2 engine prototypes, but they won’t roll them out until monitoring and safety capabilities are improved.
It’s just not demonstrated to be as economically or ecologically better than your good ol’ fossil engines.
It’s also a chicken vs. egg thing. There isn’t much infrastructure for delivering hydrogen, and no one wants to invest in a delivery method because there’s little hydrogen, because there’s little infrastructure, because there’s little hydrogen and round and round.
Hydrogen has to be produced, unlike raw oil, which just sits there waiting to be extracted. So even if the other issues of it were solved, the extreme volatility (hard to contain it) and explosiveness (using just a lighter, you will not be able to ignite diesel), there is still the issue of how to get it.
ELI5 attempt: A long time ago, humanity found a warehouse full of charged batteries. And used them, for all kinds of toys. Once a battery is depleted, it turned into a nasty fart and was gone. When the warehouse was slowly depleting humanity looked around some more, and found more warehouses of charged batteries an emptied those, too. They had to travel further and further to find them, eventually even into deserts and in the oceans, hard to get to places, but it was worth it.
Humanity however realized that there are two issues, one is that it is harder an harder to find those warehouses, and the other is that really nasty smell of farts started to build up, and it is getting really bad. People started getting sick.
Some smart guy looked down at some point, and realized that there are actually empty batteries in every lake, ocean and even puddle, everywhere, and suggested testing those. And would you know it, once charged, those batteries would work mostly fine, not emit smell, and can be used again and again. Making them work like the other batteries is just a matter of testing and some fiddeling, that they can figure out, the bigger issues it that so far, the only way to charge them was to discharge one of the old smell batteries, so nothing was really gained there. Sure, you can charge one, and show it around and everybody will say “boy this is nice, and it doesnt smell like a fart” but since there is still the issue of clean charging, there is no real benefit. Now if we had some way to create electricity in some other way, and charge those water-batteries without the fart-batteries, the problem would be solved. So some humans said “what about solar, and wind, and all those unreliable energy sources, where people said they are bad because they are not always available? Why not charge the water batteries when we have more energy that we can use to watch TV and warm our houses?” And the rest of the people said “yeah, kinda, I get the idea, but it sounds like a lot of work, and effort, and those wind turbines dont look nice. I also invested into the fart battery company and another one making gas masks. I would rather just ignore the issue, but you keep on telling people we solved it, so they tolerate the smell a bit longer and stop asking questions”.
[removed]
There’s no good large scale production method that’s environmentally friendly and it’s also hard to store and transport. Also it’s highly flammable and volatile.
Right now the main method of producing hydrogen gas is as a byproduct from natural gas, and other fossil fuel, refining. There are some other methods to produce it but none are implemented large scale due to immense power requirements, which without a reliable and powerful supply of clean energy makes the whole point of using hydrogen as an alternative energy source pointless. Once you do have hydrogen however there’s the issue that it’s very hard to contain and inevitably leaks to a much greater degree than other gases or evaporated liquid fuels do, and it’s also much more flammable, which is a dangerous combination.
Hydrogen needs to be produced using highly energy-intensive methods. In order for this to be a ‘green’ technology, that electricity will have to come from a renewable source and there isn’t enough capacity to fulfil the demand for regular electrical usage, let alone spare to harvest hydrogen. Also, at the moment it is simpler to put that energy directly into a battery using the existing electrical grid and direct home solar etc. Hydrogen will need big infrastructure changes.
Batteries are becoming more and more energy dense, meaning more car range for the same sized/weight battery. This means electric cars will shortly have ranges of 500+ miles. A hydrogen fuel cell has a range of about 400 miles. The hydrogen has already been compressed into a liquid. The laws of physics dictate that you cannot compress the liquid and make it any more dense. The only way to increase range will be to add bigger and therefore stronger and heavier tanks to cars. This in turn makes the car heavier and less efficient.
While the lithium batteries regularly used in electric cars can suffer from fires, it is nothing compared to the explosive nature of hydrogen. If you want more hydrogen onboard, you will need to figure out ways to reinforce and make safe the fuel held. Unfortunately containing a explosion usually makes it more dangerous – see a firework with gunpowder in a tight cardboard tube vs. a line of gunpowder ignited in your favourite pirate movie. This doesn’t bode well for a crashed/crashing.
In a nutshell, hydrogen has quite a few more hoops to jump through before it becomes viable, whereas the battery electric car tech already exists and improvements will be made from there.
When people talk about using hydrogen as a fuel, what they mean is hydrogen molecules (H2). There are very few of these on earth. There are very many hydrogen atoms, but almost all of these are locked up in other molecules such as water.
There are three main sources of hydrogen. The main one used at the moment is… fossil fuels. There are various methods that can be used to get hydrogen out of natural gas, oil, or coal. These are about as environmentally friendly as simply burning the fossil fuels, so it would be pretty pointless to use this to heat homes or power vehicles. Another possibility is to get hydrogen out of biomass (e.g. wood or animal waste). But this requires a sustainable source of biomass and comes with all kinds of complications depending on what substance is being used. The final source is elelctrolysis of water. This requires a huge amount of electricity – in fact, slightly more than you get by burning the hydrogen.
One possibility that does seem feasible is that hydrogen could be produced from excess electricity from renewable energy sources, at times of the day when demand is low or in places that have loads of wind/sun/flowing water but few people. However, the infrastructure for this is not in place yet, and will not be for a long time.
Latest Answers