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Hydrogen fuel cell cars (2020)

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Re: Hydrogen fuel cell cars (2020)

#161

Post by GordonS »

theluketaylor wrote: post #89
jackthezipper wrote: post #79

Earlier quoted context omitted.

While inefficiency is indeed a problem, I feel like a lot of people overlook the one huge pro hydrogen has over batteries, namely charging time. Of course this might not be important for the daily commute, or 99% of the vehicles' use. But for that remaining 1% it _is_ a huge deal. And most people buy cars to fulfill a 100% of their needs, not 99%. Now I should say, I know basically nothing about battery tech. But unl…

For passenger vehicle road trips charging time is already into "doesn't matter" territory for a number of models. I have taken a 1000 km+ trip in a BEV that I used to take in gas vehicles. We didn't have to stop more often or stay any longer than we would have with gasoline. Really think about the time you spend stationary when stopping for fuel on a road trip. It's not just pumping fuel, you also go to the bathroom,…

> We didn't have to stop more often or stay any longer than we would have with gasoline.

A serious question from someone who knows little about electric cars, and who still thought it would take anywhere between 30-240 minutes to charge, depending on charger type - can electric cars really now charge faster than the If so, I think the industry needs to make more noise about this, to make it more know.

Re: Hydrogen fuel cell cars (2020)

#162

Post by jackthezipper »

nickik wrote: post #151
jackthezipper wrote: post #148

Earlier quoted context omitted.

>that is only three 18-minute breaks Those are three _mandatory_ breaks, that add up to almost an hour, in ideal circumstances. To answer your question, not a whole lot, but in that 1% 6 hour drives aren't uncommon at all.

You are the outlier of the outlier. And if you plan it well, EV charge actually faster in the lower 50%. So if you really want to optimize you can actually do it with shorter 10 min stops. Check out Kyle from inside EV. And until you can seriously deploy Hydrogen vehicles, it would be a few years down the road. Until then the next generation of battery an charging will be significantly faster already. Practically spe…

>You are the outlier of the outlier.

I don't think I am. Camping vacations in Europe are very common. 1500 km in two days really isn't as uncommon as you might think. For clarity, I'm not saying it can't be done with an EV, I'm just saying the relatively many, long, mandatory breaks aren't nearly as convenient as the relatively few short ones that regular cars, and perhaps in the future, hydrogen cars, offer.

And again, taking a quick break to stretch your legs a bit, is not the same as needing to take a 20 minute break in order to be able to continue your journey. This might seem like a small detail but I really don't think it is.

Re: Hydrogen fuel cell cars (2020)

#163

Post by barrygwn »

boringg wrote: post #130
LeonM wrote: post #55

Earlier quoted context omitted.

You forgot safety. Hydrogen poses some serious dangers as it is odorless and colorless if it leaks. It is very easy to ignite and it is explosive at a wide range of mixtures with oxygen. [0] An hydrogen leak in an underground parking garage will be a very dangerous situation. Obviously any dense concentration of energy will be dangerous. The gasoline in a traditional car is also highly flammable (though less likely t…

Odorless / colorless -- same as natural gas. Just drop in a tracer chemical.

Unfortunately, these tracer chemicals tend to poison the fuel cells in cars. So that is not an option

Re: Hydrogen fuel cell cars (2020)

#164

Post by garyrichardson »

GordonS wrote: post #161
theluketaylor wrote: post #89

Earlier quoted context omitted.

For passenger vehicle road trips charging time is already into "doesn't matter" territory for a number of models. I have taken a 1000 km+ trip in a BEV that I used to take in gas vehicles. We didn't have to stop more often or stay any longer than we would have with gasoline. Really think about the time you spend stationary when stopping for fuel on a road trip. It's not just pumping fuel, you also go to the bathroom,…

> We didn't have to stop more often or stay any longer than we would have with gasoline. A serious question from someone who knows little about electric cars, and who still thought it would take anywhere between 30-240 minutes to charge, depending on charger type - can electric cars really now charge faster than the If so, I think the industry needs to make more noise about this, to make it more know.

I own the 400km range model 3. I can tell you that you’re comparing apples and oranges.

Over the course of the 50 weeks of a year that I don’t take it on long trips I spend 0 seconds waiting for a charge. I plug it in at night and it’s always full in the morning. A typical errand running day for me is 200+ km and I have more than enough range for that.

The one or two times I take it on a road trip I usually time it with pee breaks and filling my self with coffee.

Net/net I spend less time over all waiting to refuel my car.

Yes, of course this depends on me having a place to plug it in at night.

Re: Hydrogen fuel cell cars (2020)

#165

Post by boringg »

reportingsjr wrote: post #141
boringg wrote: post #134

Earlier quoted context omitted.

Red Herring in that --> Green hydrogen + Solar + Wind + Energy Storage are all important components of the future energy portfolio as we deleverage traditional O&G. They serve different functions and should all be targeted aggressively. I agree a Hydrogen car is a long way away though. Many more viable options in the near term. And electrolysis and plasma based hydrogen from renewable natural gas coupled with renewab…

"green" hydrogen is a greenwashing term being pushed heavily by oil and gas to make people think that hydrogen is currently low pollution, sustainable material/energy storage device. Effectively all hydrogen currently produced, and this will be true for decades, is from splitting methane.

No that is factually untrue.

Green hydrogen is electrolysis based hydrogen that uses renewable electricity OR plasma based hydrogen that uses Renewable Natural Gas with or without renewable electricity.

Anything that is made from Natural Gas is by its very nature grey or blue (per ridiculous color definitions).

The better approach is to use Carbon Intensity values but that is too difficult for the general public (and most professionals) to understand the nuances.

What you are referring to is if it is possible to roll out electrolysis quickly enough using renewable electricity to ensure that our hydrogen portfolio is net zero or at least significantly better than oil and gas as current stands.

Re: Hydrogen fuel cell cars (2020)

#166

Post by Robotbeat »

nickik wrote: post #156
_fizz_buzz_ wrote: post #118

Earlier quoted context omitted.

No way, not even close. Maybe for single seat or double seaters, but not for commercial airliners with 50 or so seats.

We already have the first 8 seater that can go around 400 miles in testing. And that is using pretty conservative battery tech. And there is a significant amount of potential optimization left. Using the batteries as load structures is just one of them, that significantly changes the simplified calculation people do on density. There are many other ideas. The problem is a lot of investment and engineering is needed a…

Yeah, it is possible to do long haul (5000km or more) electric aircraft. Difficult, but possible. 500 miles wouldn’t even be a big challenge. And “number of passengers” doesn’t even appear on the Breguet Range Equation (modified for electric flight).

Re: Hydrogen fuel cell cars (2020)

#167

Post by Robotbeat »

nickik wrote: post #152
Robotbeat wrote: post #110

Earlier quoted context omitted.

Yeah, I think seasonal storage with hydrogen makes more sense than hydrogen trucks. People often underestimate just how heavy hydrogen fuel tanks are and the required cells and especially the huge radiator you need to get rid of all the heat. I once heard that the prototype for a Nikola hydrogen truck had a heat rejection system that required just as much power as a Nissan Leaf.

Seasonal storage is a total fantasy that has no practical application in the real world if you do the math on it. Building gigantic storage with 1 year cycle is a gigantic waste of resources and even if you assume electricity to be totally free to make it pay for itself the invest most per storage would have to be like 100x cheaper then current grid storage. Hydrogen in no shape or form will every be used as seasonal…

Nah, that’s not true if you use a container with cheap enough cost per storage-kWh, for instance salt caverns. In fact we ALREADY use them for seasonal natural gas storage. The references to this toy model show how to get extremely low cost per storage-kWh, as cheap as 0.7 € per kWh. (So amortized over 20 years, that’s a pretty small addition to the energy cost). https://model.energy Details on the salt cavern hydrogen storage: https://doi.org/10.1016/j.energy.2018.05.059

Or think in context of this liquid air (or compressed air) battery.

If you can get liquid air or compressed air batteries to cost $300/kWh or so, hydrogen in the same container compressed to the same degree can store about 100 times the energy (especially if sub-cooled). So the storage cost (if dominated by the container structure) drops by a factor of ~100. That’s $3/kWh for storage, if you don’t use salt caverns. Not great if only amortized over 20 years (plus the bad round-trip efficiency), but also not terrible if it’s only used for like 5% of the electricity needs.

And that’s the real issue with seasonal storage: no one needs it really until you get to 95-100% decarbonization of the grid. Otherwise, best to use like a few gas turbines or something as backup/seasonal power. So investing a bunch of storage when you haven’t even built out a bunch of solar or wind, yet, is kind of suboptimal. Good to do demo plants, though, so you can get ready with the tech for when you DO need to decarbonize that last 5% or so.

Re: Hydrogen fuel cell cars (2020)

#168

Post by theluketaylor »

jackthezipper wrote: post #162
nickik wrote: post #151

Earlier quoted context omitted.

You are the outlier of the outlier. And if you plan it well, EV charge actually faster in the lower 50%. So if you really want to optimize you can actually do it with shorter 10 min stops. Check out Kyle from inside EV. And until you can seriously deploy Hydrogen vehicles, it would be a few years down the road. Until then the next generation of battery an charging will be significantly faster already. Practically spe…

>You are the outlier of the outlier. I don't think I am. Camping vacations in Europe are very common. 1500 km in two days really isn't as uncommon as you might think. For clarity, I'm not saying it can't be done with an EV, I'm just saying the relatively many, long, mandatory breaks aren't nearly as convenient as the relatively few short ones that regular cars, and perhaps in the future, hydrogen cars, offer. And aga…

If you're taking a family camping vacation every time you stop the car it's going to be a 15-20 minute minimum stop by the time everyone climbs out, goes to the bathroom, and gets loaded back in. I don't believe you can transport 3 or more people without needing to stop at least once every 3-4 hours.

Here in Canada things are way, way further apart than Europe and car travel to vacation is often many hours or days apart. I have taken a number of EV road trips and I have not had to stop more often or stay longer than I would have in a gas car. Charging speeds and range are only getting better, but they are already well into low/no impact territory.

Re: Hydrogen fuel cell cars (2020)

#169

Post by theluketaylor »

GordonS wrote: post #161
theluketaylor wrote: post #89

Earlier quoted context omitted.

For passenger vehicle road trips charging time is already into "doesn't matter" territory for a number of models. I have taken a 1000 km+ trip in a BEV that I used to take in gas vehicles. We didn't have to stop more often or stay any longer than we would have with gasoline. Really think about the time you spend stationary when stopping for fuel on a road trip. It's not just pumping fuel, you also go to the bathroom,…

> We didn't have to stop more often or stay any longer than we would have with gasoline. A serious question from someone who knows little about electric cars, and who still thought it would take anywhere between 30-240 minutes to charge, depending on charger type - can electric cars really now charge faster than the If so, I think the industry needs to make more noise about this, to make it more know.

I'm talking about total stop time. Pumping gas is an active task you have to be present for whereas charging isn't.

I roll into a charger and plug in, then immediately head to the bathroom. Grab food if it's a lunch or snack break. Walk around to stretch my legs. By the time I'm ready to go so is the car.

When pumping gas I can't leave the pump unattended, so bathroom time gets added on top of refuel time. With charging the car is adding range no matter what task I happen to be doing while the car is stationary.

The other charge need is daily use. Charging at home is a game changer that absolutely beats gas pumps. It takes me 10 seconds to plug in as I leave the garage. I wake up to a full "tank" every single morning. Daily errands cannot possibly use up my 400 km range, so I never have to think about charge unless I'm on a road trip.

Re: Hydrogen fuel cell cars (2020)

#170

Post by boringg »

barrygwn wrote: post #163
boringg wrote: post #130

Earlier quoted context omitted.

Odorless / colorless -- same as natural gas. Just drop in a tracer chemical.

Unfortunately, these tracer chemicals tend to poison the fuel cells in cars. So that is not an option

Surely there is a tracer chemical that could work.
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