3 ms·

It has much better energy density than batteries, which is useful when mass is at a premium (in specific circumstances because it also requires heavy apparatus)

It has much better energy density than batteries, which is useful when mass is at a premium (in specific circumstances because it also requires heavy apparatus), or when you need some backup power supply to supplement a worst case scenario that would require a prohibitively large battery to handle.

kjksf 5y ago
I'm pretty sure it's not true when you account for the wight of the hydrogen tank (as opposed to just looking at hydrogen). Toyota Mirai is heavier, more expensive, has less range and cargo space than Tesla Model 3. So it's definitely not true when we're talking about batteries vs hydrogen for passenger cars. Maybe when you scale the tank to the size of a semi it might edge out batteries, but at the moment there's no data to support this. Hydrogen is worse than gasoline / diesel. The hydrogen that is only slightly more expensive than diesel is just as much (if not more) damaging to environment. That's the hydrogen made from natural gas. The "clean" hydrogen i.e. the one made by electrolysis, is way more expensive than gasoline which is why it's almost non-existent, commercially speaking. Not to mention all the "but electric cars are not clean because coal plants!" arguments apply 3x as much to hydrogen, because due to losses you need 3x time electricity (and therefore cost) for hydrogen compared to just putting it in a battery.
- coderenegade 5y ago
  A Mirai is much bigger car than a Model 3. The better comparison would be the Model S, which has almost identical dimensions to the Mirai; when you do that comparison, the Mirai is around 300kg lighter and goes further. It doesn't matter which way you cut it, even with all of its disadvantages, hydrogen with a tank still has 3-5 times the energy density of lithium ion, and it scales better with larger vehicles. This is also the reason why industrial drones are moving to hydrogen. They've been using batteries for more than a decade now, and it's been the big limitation holding back a number of applications. Hydrogen gets you double-to-triple the endurance, even at relatively low pressurizations, which makes things like surveying easier, and delivery services possible. Military-grade platforms are supposedly already looking into using liquid hydrogen, with a number of platforms having already been converted over the past decade.

kjksf 5y ago

I'm pretty sure it's not true when you account for the wight of the hydrogen tank (as opposed to just looking at hydrogen). Toyota Mirai is heavier, more expensive, has less range and cargo space than Tesla Model 3. So it's definitely not true when we're talking about batteries vs hydrogen for passenger cars. Maybe when you scale the tank to the size of a semi it might edge out batteries, but at the moment there's no data to support this. Hydrogen is worse than gasoline / diesel. The hydrogen that is only slightly more expensive than diesel is just as much (if not more) damaging to environment. That's the hydrogen made from natural gas. The "clean" hydrogen i.e. the one made by electrolysis, is way more expensive than gasoline which is why it's almost non-existent, commercially speaking. Not to mention all the "but electric cars are not clean because coal plants!" arguments apply 3x as much to hydrogen, because due to losses you need 3x time electricity (and therefore cost) for hydrogen compared to just putting it in a battery.

coderenegade 5y ago
A Mirai is much bigger car than a Model 3. The better comparison would be the Model S, which has almost identical dimensions to the Mirai; when you do that comparison, the Mirai is around 300kg lighter and goes further. It doesn't matter which way you cut it, even with all of its disadvantages, hydrogen with a tank still has 3-5 times the energy density of lithium ion, and it scales better with larger vehicles. This is also the reason why industrial drones are moving to hydrogen. They've been using batteries for more than a decade now, and it's been the big limitation holding back a number of applications. Hydrogen gets you double-to-triple the endurance, even at relatively low pressurizations, which makes things like surveying easier, and delivery services possible. Military-grade platforms are supposedly already looking into using liquid hydrogen, with a number of platforms having already been converted over the past decade.