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Comment by exabrial | Hacker News Reader

Real Engineering did a video about this and committed the same fallacy. Engineers nearly always overlook practicality and chase perfection.

Heres the thing: It's not about efficiency, it's about convenience. Transferring 2700 megajoules of energy to an f150 via gasoline in a few minutes is very convenient, something that would take a Tesla a few hours. If consumers were concerned with efficiency the same way engineers were, we'd all be driving electric hummers and cybertrucks.

Hydrogen isn't aiming to be as efficient as batteries. It's assuming to be as convenient as gasoline, but with little environmental impact.

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Except that as we keep trying to point out, 90% of EV charging occurs overnight at home, or at work during the day. Yes, that does not cover all cases for all people, but it covers a large part and the scenario people keep bringing up is the exception to the rule that would only take place if people were on road trips or there was no charging at their residence or work.

Obsessively talking about charging times is a frame of reference influenced by decades of driving ICE vehicles. And frankly the hydrogen vehicle thing also seems like it is heavily influenced by this mindset as well.

I can't make or fill gasoline (or hydrogen) at home. After years of "refueling" my Volt this way, I'd have a hard time giving up my "gas butler" that gives me a full "tank" every time I leave my house, and having to return to going to gas stations sounds highly unpleasant and very inconvenient.

> Except that as we keep trying to point out, 90% of EV charging occurs overnight at home, or at work during the day.

This isn't a good comparison at all. You're looking at the set of people who looked at the operational requirements for EVs and said "yes, this works for my needs" and then looking at how those needs are met. What you would really want to do is compare the operational requirements for EVs and the general usage of motor vehicles to see what proportion of the general usage of motor vehicles can be replaced by EVs and their operational requirements.

EDIT: Even further, you would really want to know about the value of different modes of usage as well. So, for example, it is possible that users value edge case usage (such as very long trips) much, much higher than they do day-to-day usage and so still you could meet 90% of general motor vehicle usage with EVs at the same convenience but if the remaining 10% was far more valuable to end users and the inconvenience too high, it might still not be reasonable.

> What you would really want to do is compare the operational requirements for EVs and the general usage of motor vehicles to see what proportion of the general usage of motor vehicles can be replaced by EVs and their operational requirements.

Okay, has this been done by anyone? Something that shows current limitations of the infrastructure and projected mitigation of those?

A quick Google search doesn’t find anything official from NREL or similar DoE labs, but I’m mobile so my search is quick and not comprehensive.

The average American round trip commute is under 40 miles. Longer commutes can be accommodated with financial incentives and legal requirements for employers to provider EV chargers on prem (with pass through billing for the power, or providing it for free). Anything beyond that (high daily mileage outliers) are served by long range EVs and Fast DC charge networks.

I think the point made here is that those very requirements are tailored around a ICE world. If, say, your city bus network is designed so that each driver can make a 5 minute stop at terminus and fill up when required, of course pushing an electric bus into that will create 1-2h gaps in service and be "not fit to operational requirements". But it's a simple exercise to shift things around so that all recharging is done in low demand periods and all your fleet is online during rush hour.

The bottom line: electrics are quickly overcoming the 1000Km/charge barrier, in the next 10 years it will probably become the norm. That's a charge level that can last you a full day in almost any conceivable usage mode, so it can cover 99% of real world tasks.

Sure, there will still be very specialized tasks where 2 hours of downtime per day is unacceptable, or some fresh produce delivery route that requires 36 hours non stop driving by a shift of truckers. But that would be negligible in the grand scheme of things.

>36 hours non stop driving by a shift of truckers. But that would be negligible in the grand scheme of things.

Can you elaborate on why you’d consider trucking to be a negligible edge case? What I could find online shows it’s over 40% of commercial miles and over 60% of transport for delivered goods.

You left out this important qualifier in your quote: "[...] some fresh produce delivery route that requires 36 hours [...]". yholio was talking about a particular niche case, not about trucking in general.

Ahh, ok, I read it as two separate cases (produce delivery and long haul trucking). Thank you for clarifying

Trucking is 40% of commercial miles. Most trucks are parked for hours/ day so the driver can sleep. It'll be interesting seeing how this changes as autonomous driving becomes more common.

Some trucking companies are using a “local” model where a driver will drive 4 hours one way, drop off the trailer to another driver for the next leg, and pick up a trailer to drive back home to be more efficient

The other possible option to work around range issues with electric vehicles is to electrify our major highways so that battery capacity is no longer a concern. That would require expensive infrastructure upgrades and new standards for how to charge a moving vehicle, but it would mean vehicles could be substantially lighter and less expensive.

People don't know what they want. The fact is, the infrastructure for renting gas vehicles for long drives is already in place, and 99% of driving is short and local.

Thinking about "how much users value x" based on the CURRENT PARADIGM is a constraint to progress, and doesn't help predict very much at all. Consumer habits change.

> The fact is, the infrastructure for renting gas vehicles for long drives is already in place, and 99% of driving is short and local.

Exactly.

If you are going on a long trip, renting or renting plus flying is likely best. If you are traveling 1200 miles, do you really want to drive for 20 hours solid? I've done it and it mostly sucks.

Except now your back to using fossil fuels again.

This is the big problem pro-BEV people are missing. If your goal is to reach 100% green transportation, batteries will never get you there.

Nobody seriously expects to get to 100% green anything. Getting to 95% provides all the benefit anyone rationally hopes for. Squeezing out the remaining few percent is not worth the extra cost, much as getting the last bit of toothpaste out of the tube is not worth the bother (unless you are indulging obsessiveness).

People seriously expect fuel cell cars to allow for 100% green transport. Only from a BEV context do you talk about figuring out the last 10% or whatever.

Are pro-BEV people actually missing this? At least for now, the goal is only to remove some of the more significant sources of pollution. Vehicles for personal transport are a reasonable place to start. Obsessing about perfection is only going to hold us back.

I’m significantly more interested in saving the planet for my child than I am in driving a car with a specific powertrain. I’m pro-BEV because it seems to be a good way to move in the right direction. I drive an ICE VW but will move as soon as it makes sense to.

When I need a 4x4, I rent one.

> If your goal is to reach 100% green transportation, batteries will never get you there.

When you pose every problem as an absolute, it's impossible to come up with a solution for anything.

I'm not one to make perfect be the enemy of good. If 99% of driving is EV and 1% is ICE then we have a much smaller problem to deal with.

Not long ago, people predicted EVs would never get to the point they are now. The picture will be entirely different in 10 more years. By the time we've replaced the first 90% of ICE vehicles, the solutions to the last 10% will become more obvious than they are now.

The problem is that fuel cell cars really can take you to 100% green transportation. This is a problem that can be avoided entirely.

> This isn't a good comparison at all. You're looking at the set of people who looked at the operational requirements for EVs and said "yes, this works for my needs" and then looking at how those needs are met. What you would really want to do is compare the operational requirements for EVs and the general usage of motor vehicles to see what proportion of the general usage of motor vehicles can be replaced by EVs and their operational requirements.

The vast majority of journeys and days overnight charging of a tesla style car is fine. The average driver

1) Spends 55 minutes a day behind the wheel

2) Drives 29 miles a day

https://solarjourneyusa.com/EVdistanceAnalysis7.php

"93% of all vehicle-days show a total distance below 100 miles. It is important to note that only vehicle-days are included where the cars were used that day"

A car with a 300 mile range covers almost all drivers for almost all uses.

So you're down to whether the downsides of owning and operating a gas-fueled car outweighs the downsides of an electric car (having to hire a gas one for occasional long trips)

As more and more people move to electric, there are fewer and fewer customers for gas stations, reducing the number around, and reducing the utility of a gas car even more. The costs of repair become higher, and the cost of the car in the first place will increase as economies of scale tip the other way.

> A car with a 300 mile range covers almost all drivers for almost all uses.

Depends on charging options. If you can charge overnight at home or at the office, then yes. If your only option is spending a long time at a charging station away from home / office, an EV suddenly requires planning.

Thankfully there's more and more public chargers in or near residential areas around here.

> So, for example, it is possible that users value edge case usage (such as very long trips) much, much higher than they do day-to-day usage and so still you could meet 90% of general motor vehicle usage with EVs at the same convenience but if the remaining 10% was far more valuable to end users and the inconvenience too high, it might still not be reasonable.

How much do you weigh the inconvenience of being 10 minutes late for an appointment because you had to make an unplanned fuel stop?

How much do you value 100s of unneeded fuel stops interrupting your life?

Fortunately, it's not necessarily an either/ or. You can buy an EV for 99% of driving and just rent an ICE car when you need to road-trip.

Totally. I’m not taking a side here. I think it’s a really complicated issue. I’m excited for EVs and optimistic about their future but we have to be real about trade offs when considering other possibilities.

Problem 1) Many people don't live in houses. Problem 2) Free charging at work or elsewhere ends once a significant share of people utilize it Problem 3) electric grid can't handle the amount of capacity needed, not by a long shot.

If petroleum didn't already exist we'd be trying to create it.

There are quite a few urban areas with single occupant houses but without driveways. Most people wouldn’t want to install a charger out in their parking strip, on general principle - too exposed. Running high current wires out into the front yard and under the sidewalk would also be a mess.

And that’s all ignoring the fact that the city owns the parking strip, not you, and I don’t think they’re going to be interested in having that kind of equipment in their space.

> I don’t think they’re going to be interested in having that kind of equipment in their space.

Aren't some cities (LA comes to mind) installing level 2 chargers along the street?

That's a good point. I think it's qualitatively different for a city to decide to build charging stations on 'their' property versus a private citizen.

There's also no guarantee they'll put it in front of my house. Or if long-term that's what I want (now I get home from work late and some other EV is parked in front of my house? How do I feel about that if I have an early meeting tomorrow?)

> If petroleum didn't already exist we'd be trying to create it.

You are forgetting about the power of NIMBY!

If gasoline weren't already a vital piece of infrastructure, nobody would allow a gas station to be built in their neighborhood. Any time someone tried to build one, the pile of litigation would bury the prospective builder. This is already an issue and our society has largely taken the risks of having (literal) toxic waste at the end of their block.

NIMBY like that is only a problem in a specific environment. My gas station is 5min drive away, which in practice means out of town. Even bigger cities around here have more industrial/commercial areas. It have the gas stations attached to shopping centres. So I don't think NIMBY would affect the introduction of petrol.

Yes, EVs are a great 99% solution. The problem is people aren't willing to own a second car to take care of the other 1%, so they need their car to be a 100% solution. Most of my friends take weekend road trips to camp or visit friends in other cities, and EVs just aren't capable of those use cases yet.

No car ever made is a 100% solution, and many people do own multiple cars already.

Most people with two cars actually drive both cars every weekday. If one of them is gasoline, then you're replacing half of their gasoline consumption instead of all of it.

What those people will not do is buy two electric cars plus a gasoline car for their 1% needs. Many people also would rather not hassle with rentals on a regular basis.

But in fairness, it'd be great progress just to get to the point where most two-car families choose electric for one of them, and by the time that happens, batteries will probably be a lot better anyway.

By your reasoning they only need the rental 1 percent of the time. A lot of people use Uber more than that.

My own car is only a 20 percent solution. The rest is walking, biking, and public transit.

Uber is very convenient. Going down to the Enterprise office and filling out paperwork to take a drive out of state, not so much.

Obviously I'm not actually claiming any particular percentage, since that varies by person.

Yeah, I think EV adoption will stall out for a long time at around 50%. Families will have one EV and one gas vehicle. That covers all their needs; two EVs won't. And the gas-burner will get used just as much, since both parents need a vehicle.

The idea that people will rent vehicles for those longer trips is a bit untethered from reality.

This is 100% false and hasn't been true for a long time.

A Tesla can easily take a road trip the same as any ICE vehicle. I've personally driven one across the country. Supercharging along the way now takes the same amount of time as any normal stop for gas.

EVs are already better than a 100% solution because electricity is far cheaper than gas and you can fill up at home.

I’ve owned three Teslas and I can tell you that road tripping isn’t at all as convenient in a Tesla as an ICE.

I agree, though I'd concede that we enjoy taking the Tesla on road trips because our kids are young. Stopping at the McDonalds next to the supercharger for a restroom break, sometimes lunch, or a romp in the play area for half an hour works really well for us. If our definition of roadtripping was drive-pee-drive-pee-drive-pee-drive with no real rest stops, it would definitely be faster to take our pickup (the only gas vehicle we have left).

I can tell you quite definitively that a tesla with the maximum range possible will still not be able to get you to and from a great deal of small cities and camp grounds in the US, especially if you live outside California.

Maybe a Tesla can make a trip in the same time as an ICE, but only if you normally stop frequently. I'm a "drive straight thru" kind of person, and road trips in my Telsa frustrate me.

A few times a year, I make a ~950mi drive in my 2017 MX 100D (~295mi rated, ~220 maybe at 75 mph). In an ICE car its 13.5 hours of driving, and about 4.5 hours of charging. I frequently find myself wishing I owned an ICE car when I'm on the trip. Especially when the weather is cold, and I'm debating the range impact of turning the heat on vs 12 more hours of not being able to feel my toes. Or when the supercharger is busy and it ends up taking 2x as long to get from 5% to 45% because I'm sharing... or the anxiety of trying to make it one more charger to be able to save time by charging 2% -> 55% rather than 12% -> 65% (to avoid charging past the taper..)

I'm hoping the new models coming with 500 or 600 miles of range improve this. I'd probably only need to charge 3 times.

You need to develop a relationship with a car rental agency. And maybe an airline or rail carrier. You are putting a lot of miles on your car, reducing its value unnecessarily.

That seems unlikely to work out in their favor, if for no other reason than that car rentals turn a profit on top of depreciation and a ton of other overhead, and the cheapest rental cars are only a few times less expensive new than their Tesla.

As a ballpark estimate, each such trip would cost at least $50 after taxes and fees for a budget car rental (ignoring gas vs supercharging or any other fees that would be incurred in both situations, assuming there aren't one-way fees, etc). After 100 such trips you'd have paid $50k in rental fees, vs simply having a Tesla with an extra 100k miles. Resale value is a nonlinear function of a lot of variables, but linearizing a few portions of the parameter space for the current market an extra 100k miles would only devalue the car by at most $16k (less if they intended to hold on to it for a few extra years instead of selling it immediately while the mileage depreciation matters the most).

What they said was "a few times a year". Rounding up, that would be 25 years. In a few years, there will be plenty of electric rental cars and charger stations, and the batteries will be much better.

Right now, the most expensive wear in a Tesla is battery cycles.

The point wasn't that it works out in their favor if they make a ton of trips but not if they make a smaller number. Those figures were approximately a best-case cost for the rental and worst-case cost for mileage-induced depreciation at any point in the depreciation parameter space. If they only added 10k miles then they'd incur $5k or more in rental fees and $1.7k or less in mileage-induced depreciation by the above math.

I did misplace a zero though for what it's worth. A budget rental would only cost $500 or so over 10k miles, not $5k, if they're making the entire trip in a single day and returning it to the same place they picked it up. If that's the case the budget rental would probably be worth it financially (unless they were planning to hold the Tesla for awhile so that it hits a more favorable point in the depreciation curve), and if not then the extra rental fees are likely such that especially counting gas vs supercharging it's approximately a wash one way or the other.

If you can afford a Tesla, renting a car for 1 week a year isn't a big burden.

Yet another reason EVs aren't the dominant market yet.

Likely the single biggest reason.

I'd suspect the fact that not everyone has a convenient place to plug in overnight would be a pretty major factor. A good percentage of city dwellers in particular park their cars on the street, away from their home.

I'm surprised nobody does a product that's an EV lease plus some prepaid credit every month for a rental service, so for the one day a month you need a conventional petrol car, it's already budgeted for.

Hell, you could generalize it to small petrol cars too. I suspect most of us "overbuy" larger and more capable vehicles for the one day a month we need something bigger than a Mirage.

>Except that as we keep trying to point out, 90% of EV charging occurs overnight at home

Most people don't buy vehicles for 90% of the use-cases. They buy something that does everything they normally expect a car to do, which includes a long road trip every year or so. Maybe driving to a favorite campground 200 miles away, etc.

The reason people keep bringing these scenarios up is due to the fact that electric cars are terrible for these cases. Nobody is suggesting they can't be used for daily commutes.

Right now electric cars are for people who can afford to also own an ICE or rent an ICE for road trips (or who don't like road trips at all).

Just look at the number of pickup trucks there are, with empty (even pristine) beds. Nobody is hauling stuff most of the time, but they got a vehicle that can.

It's an emotional decision, but even with that - well under 20% of vehicles sold in the US in 2019 are trucks

https://www.goodcarbadcar.net/2019-us-vehicle-sales-figures-...

I think EVs make a great second car. I drive a Tesla, my wife drives a Bolt, and we have an F250 for towing the travel trailer, hauling household stuff around, or going somewhere that charging infrastructure is going to be inadequate (haven't really run into that yet, but the pickup is our catch-all). I can't see going back to ICE cars as daily drivers, but it'll be quite a while before we don't have at least one in our household. Especially as long as we continue to own the RV.

so, to save the environment, everyone get two cars.

Or, rather: a small enthusiast minority gets two cars, generates the critical mass required to build charging infrastructure etc., then everybody can switch directly to an electric when it becomes convenient for them.

I would use a lot more fossil fuel if I used the pickup as a daily driver. Getting an EV as a second car is the sensible choice.

Yep, well, this is why I drive a Volt and not a Tesla. The EV portion of it covers 90% of my use cases, and then I have the ICE to fall back on if I need it, which I do once in a while, mostly for ski or camping trips to places that will probably only ever get charging infrastructure in like... 20 yeras.

Too bad GM killed it from their line-up.

The Honda Clarity plugs the hole left by the Volt pretty nicely. And last I checked it's still eligible for the full federal phev rebate.

But there are a few caveats:

- The power to charge the EV is drawn from the grid

- Batteries are heavy, so you cannot scale up batteries for range

- These batteries require a lot of lithium mining

Given these, I would definitely prefer the hydrogen solution.

There is no fundamental physics reason to use lithium, it's just the current best technological node. There are many technologies that are very promising in the lab, like carbon nanotubes, iron and sodium ion, aluminum-air etc. There is massive research in this area and if none of these technologies turn out to be economically superior to Li-ion in the near future, then they will certainly be available if, for environmental reasons, lithium becomes expensive.

https://www.pocket-lint.com/gadgets/news/130380-future-batte...

It’s times like these that people should realize that fuel cells are a type of battery. You can call them hydrogen-air batteries.

That's not really accurate since the "electrolyte" changes phase requiring external storage (H2O -> gaseous H2) and the re-oxygenation step cannot be performed (yet) in the same device as the electrolysis.

It's not an electrochemical battery but I can agree with seeing it in a general sense as the an energy storage device, in the same way a dam is a "gravitational battery".

You can perform both steps in the same device. It's just more efficiency to have a dedicated electrolyzer doing that elsewhere.

- The grid where I am is 90% non-CO2 emitting; nuclear and hydroelectricity with natural gas supplimenting it. We phased out the last of the coal plants 15 years ago. More places should, the air quality in the whole province improved markedly after.

- I drive a car with a small 14kWh battery, and a backup ICE for when I need it. 90% of my miles are electric. I don't understand why this model isn't more popular. I see no need to drag around a 60kWh battery "just in case" I need that extra range.

- Lithium isn't the huge environment/social problem really. Basically big evaporation ponds in desert areas. There's even some work being done to pull lithium out of abandoned oil wells in some locations. Some of the other components are a problem, such as Cobalt in some formulations. But all these formulations can be played with. And they are one-time for the whole vehicle, rather than requiring continual extraction. And can be recycled. Can't recycle petroleum or hydrogen.

Meanwhile the only practical sources for producing hydrogen require fossil fuels, typically natural gas, and end up emitting CO2. Emitting CO2 is not necessary for EV usage. But most practical sources of hydrogen do. And the efficiency is far lower.

Fast charging is also arguably the least environmentally concious way to charge any electric vehicle.

A) fast charging causes battery degradation at least 3-5x as fast as charging at or below the nominal "C" rating of a given cell or amortized individual cell rating. This means, in the next 10 years, more batteries have to be produced, more lithium has to be mined and more Tesla parts have to be shipped on diesel powered vehicles. [0][1]

B) it uses more power and places more demand on the grid, hence you're burning more coal in order to meet the demand curve and incur a larger transitional period in production which means more fossil fuels burned, more energy lost to conversion and at the end of the day more Co2 in the air. [2]

0 - https://cleantechnica.com/2017/07/09/tesla-limiting-supercha...

1 - https://cleantechnica.com/2020/01/12/is-it-true-that-a-tesla...

2 - https://afdc.energy.gov/files/u/publication/ev_emissions_imp...

I could see an interesting appeal in focusing on getting to a 1-hour or 30-minute charge time. because that allows for some structural changes to an entrenched business model.

The current gas-station/convenience-mart ecosystem is designed around a 5-minute or so petrol fueling cycle. There's nothing they offer that will keep you productively occupied for a hours-long charge cycle.

A 30-minute or hour charge cycle, in contrast, is long enough to perform errands-- I could see a large number of supermarkets, strip malls, big-box shops, and restaurants interested in offering 1-hour charging stations. You can offer cross-promotions (spend $100 in store and your charge is free) and you have captive customers who are likely to wander the aisles a bit longer/order an extra coffee or dessert if they know they need to wait another 10 minutes for their charge to complete. Maybe the no-garage apartment dweller does his charging when he goes for his weekly grocery run.

Love it. The same for motels, roadside attractions etc. Once a sizable fraction of motorists require it, businesses will bend over backwards to provide it subsidized, to acquire customers for their main cash vector.

And electric is intrinsically democratic, if you have civilization you have electric power around. Some upgrades will be required but from a single business' point of view, the investment is much lower than building underground fuel storage tanks, obtaining the necessary environmental and zoning permits etc. Literally anyone can enter the charging market.

> that would take a Tesla a few hours

Even with "version 2" superchargers, this is not true. With 250kW (v3) charging, you can get to a sufficiently high state of charge (>80%) in under 30 minutes. And the thing is, given how efficient an EV is, you don't need 2700 mega-joules (20 gallons of gas or 750 kWh) to go ~500 miles. The Cybertruck will do that range to with ~100-150 kWh of battery and charge up in under an hour. This will probably get faster over the coming year as charging rates go up.

And like another comment pointed out, majority of charging happens overnight or during the day when the car sits idle. I own a Model 3 myself and I have not been to a supercharger in several months.

This is a point that needs to driven home.

Yes, filling up gasoline delivers energy at an insanely high rate due to its density but the vast majority of that is wasted and not converted to miles driven.

The real comparison is miles of range delivered per minute of fueling. And a Tesla supercharger is already competitive with gasoline by this metric. If hydrogen takes longer than gas to fill up a tank for a similar range then its already behind just charging directly.

20 gallons of gas still only takes 5 minutes to fill. If I can get 125 KwH in 30 minutes with your v3 charging that's still a 6x multiplier, not really something you can ignore.

Now you need bigger charging stations because people are spending longer at the pump or else you'll have longer lines. Adding to that, I sure as hell am not spending half an hour at a pump on an already long road trip.

The lack of population density in the US, especially in the middle of the country, makes electric vehicles not a great choice for many people. I'm guessing this is why we see higher adoption in Europe on a consumer and infrastructure level.

I live in Iowa. It's about as "middle-of-the-country" as it gets. Lines at charger stations are really a California problem as of now. I have never encountered it driving throughout the midwest and I have gone on some long road-trips.

As for taking 30 minutes to charge, what people usually do is to make sure their charging stops line up with food/bathroom breaks. Realistically, if I drive 10-12 hours in a day, I would stop about 3-4 times for food/bathroom breaks, if not more. This lines up perfectly with the range in my Model 3 AWD. In many cases, I have ended up having to get up and go get my car to avoid idle-rates because it finished charging while we were still eating.

On these trips, I usually pick a hotel/B&B with destination charging so that I can get going in the morning the next day with a full battery.

The "6x" is a number to ignore, because it's focused on one tiny part of the trip. If you can drive all day long with 1 stop, then the extra 25 minutes only makes you a few percent slower.

> Hydrogen isn't aiming to be as efficient as batteries. It's assuming to be as convenient as gasoline

And it won't be. H2 is terrible for convenience of handling compared to gasoline. Handling liquid H2 is a nonstarter, it liquefies at 21 K at atmospheric pressure; cryogenics like that are not convenient at all. Gaseous H2 will escape through every tiny gap in whatever containment setup you choose, plus it's highly flammable, much easier to ignite inadvertently than gasoline.

And to top it all off, at the end of the day, its available chemical energy per unit mass is only two to three times that of liquid hydrocarbons. That's simply not enough of an advantage to overcome all the downsides.

What H2 can be used for is to make liquid hydrocarbons, through various chemical processes.

Hydrogen is also notoriously low density, even in liquid form. It embritles metals on contact. Hydrogen fires are invisible during the day (if you see rocket engineers walking around with broom pointed forward in front of them, that's why).

Personally I count on hydrogen for high energy space propulsion (either chemical with oxygen or alone in a NERVA for NTR) as otherwise it's IMHO too much of a headache to work with in practice.

It doesn't just escape through tiny gaps. It's small enough to permeate through any material we use to contain it.

Using electricity usually is even more convenient, since you can do that at home, and very few of us have gas station in the garage.

I charge my electric Hyundai with a normal power outlet, and every once in a while I fast-charge it. 99% of the time that‘s good enough already. If we‘re going by convenience, plugging in at home is probably more comfortable than driving to a gas station, waiting 5 minutes, paying, and driving back.

> Heres the thing: It's not about efficiency, it's about convenience. Transferring 2700 megajoules of energy to an f150 via gasoline in a few minutes is very convenient, something that would take a Tesla a few hours. If consumers were concerned with efficiency the same way engineers were, we'd all be driving electric hummers and cybertrucks.

There are 2 types of convenience.

- Being able to fuel up quickly on a long trip

- Having your fuel tank full at the beginning of every single trip.

Hydrogen fuel cells (and combustion engines in general) are better only for the former case. Since most people drive less than 300 miles most of the time, it's hard to argue a car optimized for longer trips is more convenient for most drivers.

75 kWh doesn't take a few hours with a supercharger. Doing similar with hydrogen is probably a similar level of infrastructure.

> Transferring 2700 megajoules of energy to an f150 via gasoline in a few minutes is very convenient, something that would take a Tesla a few hours.

A 75% charge can happen in ~20 minutes on something like a 250kw Telsa super charger. Battery tech and battery charging tech will only get better/faster. Also the vast majority miles driven on the road aren't "road trip" miles in which you would see the drive-to-fuel/energy exhaustion over and over for days on end scenario. When a Tesla plugs in at home and charges over night, that's actually more convenient than having to go to a gas station.

and economics. If I can make an H2 vehicle for less than it cost me to make a gas or electric vehicle, it's worth my time and money to push into or even create a market that'll buy them.

>Heres the thing: It's not about efficiency, it's about convenience.

>Hydrogen isn't aiming to be as efficient as batteries. It's assuming to be as convenient as gasoline, but with little environmental impact.

Energy conversion efficiency is pretty important for that "little environmental impact" part.

Also, it’s not just an option for passenger vehicles. Natural gas can be replaced with hydrogen in the existing pipeline network, providing distribution of heating gas at extremely low cost and with a very minimal investment in retooling of existing furnaces.

Hydrogen pipelines with probably never be a thing. It's safer and more convenient to just produce h2 at the distribution point. The oil refinery/pipeline model exists because of the difficulty in synthesizing hydrocarbons, whereas h2 is (relatively speaking) far easier to create.

I believe OP is thinking more municipal pipes that feed individual buildings rather than a distribution pipeline like Keystone XL.

Aside from blending small amounts on hydrogen in existing methane feeds, no one will do this. Pure hydrogen is a dangerous gas that burns much hotter than methane, can seep trough the tiniest of cracks that methane/propane cannot and can even penetrate the crystal lattice of common metals such as steel, leading to embrittlement and catastrophic failure under normal use. By the time you upgrade the methane infrastructure to handle it, you will build a whole network all together.

And there is also an economic argument: methane/propane work because they are pure energy coming from the ground, you can only burn them to recover it. To produce Hidrogen, you need electric energy, or some very hot source that could be turn to electricity at a high efficiency. It makes zero sense to generate hidrogen in order to burn it for domestic heating, when the equivalent electric energy could give 3-5 more heat using electric heat pumps.

It looks like you can blend something in the neighborhood of 10-15% hydrogen into the existing natural gas infrastructure without negative consequence. That's not game changing, but it's a significant environmental improvement if you're using renewables to produce it. It's a fine way to utilize daily or even seasonal renewables overproduction in a useful way without blowing up tons of existing infrastructure. Many diverse steps - some small, some large - are needed to get ourselves to a carbon negative lifestyle.

>>To produce Hidrogen, you need electric energy, or some very hot source that could be turn to electricity at a high efficiency.

This is not a true statement... Aluminum alloys readily liberate H2 from H20 at room temperarure (an exothermic reaction generating roughly equal parts thermal and chemical potential energy - both of which of course can be used for work) [1].

The oxidized aluminum is environmentally benign and can be recycled by applying more energy to deoxydize the product. The 'purification' process is ultimately where the useful energy comes from. The energy to power the purification can come from any number of sources - but as good stewards, we opt for clean energy sources. Al smelting historically produced a lot of carbon, but thanks to R&D by Apple, there are new carbon-free alternatives for this process [2].

At my company we are researching application of this energy infrastructure loop for powering ships (where source water is abundant). Essentalially, the Al+ is your fuel (battery), and from a volumetric energy density perspective (important for ships), you can store about 2X as much as gasoline/diesel - and way better than liquified or compressed H2 storage. However, on a mass energy density perspective (important for automobiles), it is a bit worse (heavier) than hydrocarbon fuels. Again though, each application has it's own constraints when considering an energy storage medium.

The automotive or civil sectors aren't the only use-cases for hydrogen fuel cells. One needs to take a look at all sectors to really grasp the global impact. A large part of my job is to explore this big-picutre aspect, because we need to understand the long term infrastructure stability/availability of potential "clean" energy supply chains, and it's VERY complex when you consider process efficiencies over the entire supply chain, raw material abundance and regeneration potential/economics/environmental impacts/speed, geopolitical forces affecting supply chains, the list goes on and on (and on).

H2 is an interesting "energy storage" option and it will certainly continue to be researched and applied broadly.

1. PDF - https://www.google.com/url?sa=t&source=web&rct=j&url=https:/...

2. https://www.apple.com/newsroom/2018/05/apple-paves-the-way-f...

100% of aluminium is made with electrical energy...

Actually, Al+ is purified by smelting, which is powered by applying thermal energy to a sample. As I alluded in my comment above, you can generate the thermal energy by any number of modes of energy transmission (electrical, chemical, RF radiation such as concentrated solar, nuclear, etc.).

The primary point of the above comment was that you need electrical energy to produce H2. That's a false statement. Al+ can generate H2 without electricity.

The important point is that the energy efficiency of any cyclic energy carrier system (batteries/chemical, mechanical, intertial, etc.) is only one, albeit important, factor. Other factors include mass and volumetric energy density, motion/environmental stability, cost, and so forth. The importance of each of these factors is weighted differently based on the application (e.g. automobiles, ships, trains, aircraft, domestic use, etc.).

> Aside from blending small amounts on hydrogen in existing methane feeds

What's "small"?

20% hydrogen on existing grid in place now: https://www.theguardian.com/environment/2020/jan/24/hydrogen...

100% hydrogen trial over next few years: https://www.msn.com/en-us/news/technology/scottish-homes-wil...

Hydrogen has suddenly skyrocketed up the agenda in Europe this year. There is a pressure group called Hydrogen Europe (which oddly doesn't even have a wikipedia page) which comprises companies like BP, Shell, Total, Equinor, Repsol, Engie, OMV, PKN Orlen, Hellenic Petroleum, and many more. At the same time almost 100% of hydrogen used in europe comes from oil.

It concerns me how much government subsidy (both cash and regulations) is being pushed into hydrogen.

https://www.thisismoney.co.uk/money/markets/article-8970377/...

"Hydrogen companies were given a boost this week after the Prime Minister vowed to inject £500million to 'turn water into energy' as part of a 10-point plan for Britain's green recovery.

However, critics say the targets are nowhere near enough compared to Germany's and France's respective plans to invest €9billion and €7billion in hydrogen."

Everything has gotten subsidies in the past. Coal got it in Germany, Spain, Rusia,Poland, Norway and of course England. Places like current Bangladesh supported coal mines in England.

Certainly oil got it later, but few places in Europe had it compared to coal. Refineries grew costing lots of billions.

Then natural gas got it with the investment of big gasoducts.

Then it was renewables. Hydrogen is just the next step, because it is the cornerstone of the chemical synthesis process, not just transportation.

Hydrogen and electricity are just "vectors". They let you use coal,gas,nuclear, hydro or Eolic power to power your cars and trucks with much less dependency on US controlled oil for industry and transportation.

> Aside from blending small amounts on hydrogen in existing methane feeds, no one will do this.

The province of Alberta, Canada has put hydrogen at the core of its energy development strategy. The idea is to use existing natural gas pipelines to transfer hydrogen.

It’s true that a small fraction of hydrogen will permeate the pipes and leak; however, that leakage is not economically significant:

“... this theoretical distribution main leakage rate (43 million ft3/yr) would be 0.0002% of the 24.13 trillion cubic feet of natural gas consumed in 2010.” [1]

Hydrogen can be blended with natural gas (the above calculation was made assuming a 20% blend) or it can be sent down the line exclusively. As for how the hydrogen is produced, there are several ways:

1. It can be cracked from natural gas, after which the carbon is captured and stored back underground. Or,

2. It can be produced from electrolysis of water using energy from a renewable source such as wind or solar, effectively storing the energy for later use.

Either way, the point is that hydrogen is a useful fuel that can be transported over existing infrastructure and then used in a variety of ways that may help with the transition to a zero carbon system. Just to give one example, hydrogen can be combined with carbon dioxide to create jet fuel. [2]

[1] https://www.energy.gov/sites/prod/files/2014/03/f11/blending...

[2] https://www.nature.com/articles/s41467-020-20214-z

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