Hydrogen and FCEVs discussion thread

[Oilpan4]

The only application I can find for electrolysis derived hydrogen is research grade hydrogen.
Even then I don't think water is normally used, think it comes from lye production then is further refined.
The petrochemical industry makes millions tons of hydrogen every year.
So the excuse "we don't have hydrogen powered cars because there is no way to produce a lot of hydrogen" doesn't work.
Most of the hydrogen comes from natural gas and oil refining. The biggest uses are hydrogen are making ammonia and hydro cracking oil products.

[WetEV]

Wikipedia still showing high temperature, high pressure electrolysis might be able to reach 50% efficiency.
So unchanged since 2006.

Last time I looked it up 70% is about double the electricity to hydrogen conversion efficiency anyone had been able to demonstrate.

Considering the industrial production of hydrogen, and using current best processes for water electrolysis (PEM or alkaline electrolysis) which have an effective electrical efficiency of 70-82%,[40][41][42] producing 1 kg of hydrogen (which has a specific energy of 143 MJ/kg or about 40 kWh/kg) requires 50–55 kWh of electricity.

[Oilpan4]

So just the hydrogen production is less efficient than the lithium ion batteries.
I don't think this existed 13 years ago.

But still have to compress it and have fuel cell losses.
Hydrogen from fuel cell to wheel efficiency in a car is around 60%.
Looks like it takes about 1kwh to compress 1kg of hydrogen to 5,000psi.
(In theory)
1 Kg of hydrogen contains what about 33kwh or so?
Not bad. We can just say compressor losses are insignificant.

So what are we looking at. Take an energy input of 1, turn that into 0.8 making the hydrogen, then run that hydrogen in a 60% efficient machine, end up with about .5 of what you stated with. That's probably optimistic. Better than what I thought it would be, but still really horrible.

It's better than a gasoline powered car, but that's not saying much.

[WetEV]

So what are we looking at. Take an energy input of 1, turn that into 0.8 making the hydrogen, then run that hydrogen in a 60% efficient machine, end up with about .5 of what you stated with. That's probably optimistic. Better than what I thought it would be, but still really horrible.

It's better than a gasoline powered car, but that's not saying much.

It's also better than lead acid batteries. 40 years ago, hydrogen looked like the best alternative. Lots of problems, sure, but something that would work.

[SageBrush]

So just the hydrogen production is less efficient than the lithium ion batteries.
I don't think this existed 13 years ago.

But still have to compress it and have fuel cell losses.
Hydrogen from fuel cell to wheel efficiency in a car is around 60%.
Looks like it takes about 1kwh to compress 1kg of hydrogen to 5,000psi.
(In theory)
1 Kg of hydrogen contains what about 33kwh or so?
Not bad. We can just say compressor losses are insignificant.

So what are we looking at. Take an energy input of 1, turn that into 0.8 making the hydrogen, then run that hydrogen in a 60% efficient machine, end up with about .5 of what you stated with. That's probably optimistic. Better than what I thought it would be, but still really horrible.

It's better than a gasoline powered car, but that's not saying much.

From wikipedia it goes more like this:
Start from 60 kWh electricity
Spend 30% converting to 42 kWh gaseous H2
Spend 7% pressurizing to 39 kWh (I think 5,0000 psi) H2 (1 Kg H2 is 40 kWh
Spend 40% in the fuel cell for 23.4 kWh electricity that is routed to the car motor.

So the source fuel is 2.5x more expensive ... but you still have to pay for the electrolysis plant, the transport to the fueling stations, and the car fueling station. The latter is ~ $3 million a station. If we presume that a hydrogen fueling station can replace a petrol fueling station in terms of throughput and utilization, it will cost $500 Billion to outfit the US. Compare that to the cost of installing an outlet.

And now buy a fuel cell car. One interesting aspect of fuel cell cars that is not widely recognized is that they are actually H2-electric hybrids. This happens because fuel cells capable of delivering peak power desired by consumers is **way** too expensive so they are built as hybrids with a battery supplying some of the power output. All the parts of a BEV in the fuel cell car ... and all the inefficiencies (inverter, converter, battery, motor) on top of the fuel cell inefficiency. And by the way, platinum is the typical catalyst for the fuel cell. Platinum !!

It is said by optimists that electrolysis efficiency will reach 80%, and fuel cells will reach 70% efficiency in the future. I'll wager good money that cell batteries will drop to $50 a kWh for the manufacturer, energy density will double, and charging speeds average over 200 kW long before the hoped for H2 improvements. In fact, way before. Tesla is already at $100 a kWh and my EV averages about 150 kW charging.

In its own way, H2 is no less idiotic than nuclear, and it tends to be hawked politically by the same fools.

[WetEV]

In its own way, H2 is no less idiotic than nuclear, and it tends to be hawked politically by the same fools.

I'd be interested in your solution to the last 10% problem.

It's fairly easy to see how solar can replace about 40% of fossil fuels, even without storage. Just build enough solar capacity. Plus wind and hydro, but there are limits to how much.

Still easy to see how solar plus battery storage can get to 80% to 90% renewable power at a cost similar or lower than fossil power. Especially with $50 per kWh batteries in the near future.

The last 10% isn't so easy.

Both hydrogen and nuclear are possible solutions.

What is yours?

Short term storage, Li ion batteries are hard to beat. This is why FCEVs are likely doomed, even the fork lifts. Sure, fuel cell power fork lift can displace lead acid battery powered fork lifts, but I don't think that is the end of the story. But long term storage is a different matter.

[SageBrush]

In its own way, H2 is no less idiotic than nuclear, and it tends to be hawked politically by the same fools.

I'd be interested in your solution to the last 10% problem.

Ask me when we are at 80%

[Oilpan4]

Platinum is cheap right now I have 11 ounces of it.

I generally do not care for hydrogen powered vehicles. Right now and for the forseeable future everything available now is a better option than hydrogen.

Why do you hate nuclear so much?
The really dangerous power plants are obsolete gen 2 boiling water plants.
Up to 10% of the electricity generated for about the last 20 years came from surplus soviet nuclear weapons in the megatons to mega watts program.
Be careful what you wish for you just might get it.
If US nuclear power plants were close their capacity would be taken up by coal and natural gas plants and additional fossil fuels plants would have to be built.
Then there would be no incentive to ever find a final solution for nuclear waste, all the raw reactor waste in temporary storage at about 100 US sites could sit forever in temporary storage. There would be no demand for recycled fuel and there would be no fresh fuel to deal with. So no need to hurry up.
Demanding a solution for recycling nuclear waste would be better than just wanting it stopped. As we saw with Fukushima, just pulling the plug on nuclear is bad.

[Titanium48]

In its own way, H2 is no less idiotic than nuclear, and it tends to be hawked politically by the same fools.

I'd be interested in your solution to the last 10% problem.

It's fairly easy to see how solar can replace about 40% of fossil fuels, even without storage. Just build enough solar capacity. Plus wind and hydro, but there are limits to how much.

Still easy to see how solar plus battery storage can get to 80% to 90% renewable power at a cost similar or lower than fossil power. Especially with $50 per kWh batteries in the near future.

The last 10% isn't so easy.

Both hydrogen and nuclear are possible solutions.

What is yours?

Short term storage, Li ion batteries are hard to beat. This is why FCEVs are likely doomed, even the fork lifts. Sure, fuel cell power fork lift can displace lead acid battery powered fork lifts, but I don't think that is the end of the story. But long term storage is a different matter.

Lithium ion batteries are the best way we know of to store electricity at small to medium scale at near-ambient temperatures. Falling costs will eventually make EVs with hundreds of kWh available and affordable, but resource limitations will prevent lithium-ion from scaling to the petawatt-hours needed for the world's power grids to be fed by fully renewable sources.

However, a bit of 1960s battery technology might - the sodium-sulfur battery. Ford thought they would be great for EVs, but keeping a car battery at 350°C is a problem. Not so for a large industrial installation though, and all of the components (sodium, sulfur and aluminum oxide) are readily available in massive quantities. They could be located underneath the panels at large-scale PV installations, at electrical substations, as well as at facilities requiring high power on an intermittent basis (like the large scale DCFC stations with dozens of 200+ kW chargers that will be needed along major highways when EVs really start to replace ICEVs).

[Oilpan4]

Just keep the battery warm with some plutonium 238.