161–170 of 271 posts
Earlier quoted context omitted.
Energy density of hydrogen per litre is few orders of magnitude lower than that of petrol. Really the only saving grace of hydrogen vs batteries is the speed of refueling.
If someone invented a cheap round trip processing method CO2 -> petrol then EV's would have a hard time I suspect
Earlier quoted context omitted.
I still think there is a limit in chemical density that cannot be overcome without significantly changing technological principles of current batteries. Maybe hydrogen fuel cells would be a better solution after all if we can find an efficient way to contain it. Easier said than done...
Energy density of hydrogen per litre is few orders of magnitude lower than that of petrol. Really the only saving grace of hydrogen vs batteries is the speed of refueling.
Earlier quoted context omitted.
If someone invented a cheap round trip processing method CO2 -> petrol then EV's would have a hard time I suspect
But we would still need batteries to store regenerative braking energy (i.e. it would be a hybrid).
https://newatlas.com/nawa-technologies-carbon-ultra-capacito...
https://newatlas.com/nawa-nanotube-ultracapacitor-production...
Formula E would be a good proving ground for them.
Earlier quoted context omitted.
bicycles / scooters have a limited application though - families with young kids, long trips, older people, people with injuries, its raining, are just some of the groups / times these are excluded. Cars still are superior general purpose solution for travel.
You'd be surprised how much a simple bicycle or scooter cab can accomplish in solving this objection. These are very popular in Asia. The main limit is carrying capacity - maximum power - and you really do not need that much stuff. This works long range too, and could work even longer range should there be proper cargo trains for bikes. But there aren't. The trip time is typically needed to be less than 10h or you ne…
Earlier quoted context omitted.
Energy density of hydrogen per litre is few orders of magnitude lower than that of petrol. Really the only saving grace of hydrogen vs batteries is the speed of refueling.
Still better than current batteries. You could pump that up if you store it in a liquid state to a level above common fossil fuels. Not saying you don't open a can of worms for implementing it...
Earlier quoted context omitted.
I still think there is a limit in chemical density that cannot be overcome without significantly changing technological principles of current batteries. Maybe hydrogen fuel cells would be a better solution after all if we can find an efficient way to contain it. Easier said than done...
Energy density of hydrogen per litre is few orders of magnitude lower than that of petrol. Really the only saving grace of hydrogen vs batteries is the speed of refueling.
Earlier quoted context omitted.
Still better than current batteries. You could pump that up if you store it in a liquid state to a level above common fossil fuels. Not saying you don't open a can of worms for implementing it...
Hydrogen in liquid state leaks out of any container that you put it in. 70kg lead bottle stores only 1L of hydrogen and all of it evaporates naturally in 1-2 months through the metal. So no, storage of liquid hydrogen is a terrible idea.
Earlier quoted context omitted.
bicycles / scooters have a limited application though - families with young kids, long trips, older people, people with injuries, its raining, are just some of the groups / times these are excluded. Cars still are superior general purpose solution for travel.
Young kids: Cargo bike. Long trips: Car or public transit is better for most people. Older people: Tricycle/electrical assist bike People with injuries: Tricycle, recumbent bike, hand pedals, electric assist etc Rain: rain coat.
And even if not, what would you gain with these weird single purpose vehicles that can't be used while remaining in comfort and need to be replaced every winter over a multi-purpose super-comfortable shared microcar? It's not even economical or ecological, ordinary bikes/scooters + microcars + public transport is the ecological/economical solution.
Earlier quoted context omitted.
It's perhaps a more limiting factor now than then. As the article notes most EVs at the turn of the century had a range of 40-70 miles. The model T of around 1910, ten years later, had a range of about 90. Earlier ICE cars were down nearer EVs. A century ago battery and ICE technology were not that far apart. i.e. both fairly primitive. If electrics had been chosen and had 100 years of continual minor incremental imp…
we're also omitting the steam car. Where the maintenance and dirtiness were their major detractors, refined fuels and new burners solve these. Steam engines can and could have been refilled at any gas station, could run on any multi fuel including biodiesel. They theoretically require less maintenance, no oil changes, no cooling system. They'd also have had greater range and greater top speed (though less acceleratio…
How can this be true?
Earlier quoted context omitted.
Energy density of hydrogen per litre is few orders of magnitude lower than that of petrol. Really the only saving grace of hydrogen vs batteries is the speed of refueling.
Am I misreading the gp's cited chart? According to that, it seems like hydrogen is only a factor of around 4x worse in terms of volumetric energy density, and is better than petrol in weight density.