Submitted by FDuquesne t3_10gquk6 in Futurology
Taxoro t1_j54jf43 wrote
Seems like a strange concept to direct inejct hydrogen into a diesel motor when fuel cells will always have a higher efficiency without the need for diesel. Hydrogen isn't cheap, and it's made from either fossil fuels or from electrolysis. Even with electrolysis you are now losing so much energy that it's not very green(Even renewables emit co2).
Why not just replace with fuel cells?
CAElite t1_j54uldn wrote
JCB actually go fairly deeply in depth about this https://youtu.be/bfS012FC8yM
Essentially batteries just aren’t viable within the usage scenario & weight requirements of plant equipment. As well as the capital expenditure.
The capital expenditure for fuel cells just doesn’t work in the current market.
On site hydrogen production works well with many site power grids and JCB project it being fairly plentiful in the future.
Tostino t1_j553mkl wrote
Right. I tried to source a fuel cell for a project just to see how practical it would be...no fucking way at the moment. It's ~40-60k to get a reasonable amount of power out of them right now.
A simple 1kw fuel cell is sitting at like ~6k.
CAElite t1_j55nc06 wrote
Yeah, in the video I linked he actually goes into the life cycle costs, fuel cells & batteries just don’t make sense in their current state vs hydrogen combustion, even if it is some 30-40% less efficient.
Personally I can see this carrying forward into other alternative fuel situations such as transportation, with budget & enthusiast markets, where efficiency plays second fiddle to cap ex or method of operation, alternative/carbon free fuel (hydrogen ultimately) ICE is here to stay.
stivo t1_j551lqv wrote
It's expected the price will drop. Also, building all new trucks to be green is not going to help reduce GHG.
Taxoro t1_j552d7y wrote
You don't need a new truck you need a new engine.
stivo t1_j553jba wrote
You obviously haven't thought this through. You every looked under the hood of a Toyota mirai? You would need to replace all electrical and mechanical ancillary equipment. All the looms. Even the wheel hubs if you want regen braking. The entire drive train basically needs to be replaced. Different heaters, AC compressors, radiators and cooling systems. Then you need to find extra space for the battery. Yes that fuel cell needs to power a battery which then powers the motor. You would be left with the chassey and the cab basically. The amount of labour cost would be higher then a new truck. But heaps more GHG
earthman34 t1_j57p89v wrote
The price will not drop. It will increase.
stivo t1_j57rqkm wrote
Hydrogen will definitely drop. When they make it at scale it'll be heaps cheaper.
earthman34 t1_j589xc5 wrote
You have no clue how markets work. As soon as there's demand, the price will increase, not go down...in the same way the price of electricity is increasing even as more and more wind and solar comes online. "Make it at scale"...how? By cracking it from hydrocarbon? This is not only not green, it creates more carbon than just burning the natural gas. This is the only "at scale" method that currently exists. Increasing the scale doesn't decrease the refining cost, because the energy cost doesn't change. It takes around 33kwh per kilogram using electrolysis. A kilogram of hydrogen is like a gallon of gas. Hydrogen is currently around 5-6 times the cost of gasoline here in the US, without even beginning to delve into the difficulties of storing, transporting, and figuring out how to actually get it into a car. It's a red herring.
stivo t1_j58rvtf wrote
You are so confident and so wrong. I am not going to waste any more time on this conversation. Look up Dunning Kruger effect.
earthman34 t1_j5c1q9r wrote
I suspect you're leaving the conversation because you can't prove me wrong. Here's what I suggest: go buy yourself a tank of hydrogen, hook it up to your car and get it to run, and then devise a method to refill this quickly and conveniently. Do this, and then come back here and continue the discussion about the practicality of hydrogen as a combustion fuel.
But before you go to all that trouble, let me give you just a little fyi. You see, unlike you, I've actually worked with this shit in the past doing plastic brushing. I've actually handled hydrogen. The stuff is violently explosive, extremely flammable and completely odorless and colorless. It also burns with no visible flame. Leaks are about impossible to detect. A standard size 300 steel compressed gas tank is about 5 ft tall and about 10 inches in diameter and weighs about 132 lb. At 300 bar (4500 PSI) this tank will hold maybe a kilogram of hydrogen. A kilogram of hydrogen is equal to about a gallon of gasoline in pure energy. So you can start to get some kind of idea just how much hydrogen you would actually need to drive your car even a short distance assuming you could devise a system to deliver it... Which I'm assuming wouldn't be too difficult because it would be similar to the natural gas delivery systems which are in fairly wide use in the trucking industry right now, and which have been around for decades. I actually had a van years ago with a dual-fuel CNG conversion. Total pain in the ass. Huge tank hanging underneath gave a range of maybe 120 miles. Only one place in town to fill it, 20 miles away. Took it all off and threw it away. So there you go. There's your Dunning-Kruger epic.
saberline152 t1_j54ui5x wrote
because these kinds of engines already exist, made in the 90s early 00's by BMW as a study, they require 1,5 times the amount of resources to make than regular engines. However when dealing with heavy machinery like this that is less of a concern since they are not made in the same number as regular cars.
Taxoro t1_j54vj92 wrote
Include the increased resources from still using gasoline, and the reduced effiency meaning more hydrogen needed, surely the environment and even economical aspect would favor fuel cells?
saberline152 t1_j54w06r wrote
yeah possibly. I don't know the numbers for that, it's just that some companies see this and go: oh neat the R&D was already done for us together with oh neat we can say it's greener* and add to that some interest groups and we get this.
The vehicle will have a reduced CO2 output tho. if you don't factor in how most of the current H2 is made...
Schemen123 t1_j552mlw wrote
Also a lot of big engines really benefit form a hybrid approach because at that size a lot of power goes into auxiliary systems and those dont run well of diesel engines.
earthman34 t1_j57p2qu wrote
Where are these fuel cells? They don't exist.
Taxoro t1_j599e65 wrote
Fuel cells don't exist? what are you on about?
earthman34 t1_j5cfsom wrote
They don't exist in any meaningful quantity.
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