Hydrogen fueled ebikes...

[erider_61]

The Pragma Alpha2.0 has a Brose 36V electric motor, and lasts up to 100km on a single charge. With a 2 min refuel time these bikes convert hydrogen into electricity. https://www.welovecycling.com/wide/2018/02/01/future-now-hop-hydrogen-powered-bike/

 

[6zfshdb]

Recharging seems to be the major stumbling block with this bike. The article isn't clear on how the recharging process actually works. It mentions a 2 minute recharge time but doesn't say if the bike is charged via electricity or hydrogen gas. It mentions a pricey 30,000 eu "charging station" which indicates the bike requires a gas recharge. Until hydrogen vehicles and charging stations become commonplace, this bike will be difficult to charge while on the road and away from home.

This bikes 100km range can be equaled by many e-bikes on the market today. The long, 4 - 5 hour e-bike battery recharge problem can be easily overcome by getting multiple batteries. Aside from perhaps a lighter weight, I don't see any advantage of this hydrogen cell bike over an all electric model. This is especially true now considering the higher price.

 

[erider_61]

"One kilo of hydrogen is a source of 600 times more energy than a lithium battery of the same weight."

I think the dramatic difference in energy potential makes this technology worth pursuing. Economies of scale will bring the price down. The 30,000 euros was the cost for a commercial charger able to fill multiple vehicles during the day. The bike itself is 7,500 euros

"Already 100 complete Pragma Alpha bikes were sold during the last year to owners from France, Germany, Norway, the United States or Italy."

Obviously these customers must have a smaller charging station of some type and the company has been providing fuel cells to the military since 2004.

 

[Roxlimn]

Yeah. About that. The bike looks really heavy. The weight gains of hydrogen only matter when the relative weight of the generator is small compared to the weight of the bike. If the generator itself is the weight of the battery, then you didn't reduce the weight of the bike. Recharging time will matter less and less as batteries become more powerful and more compact. Already, cheaper commercially available ebikes that can be charged off the wall have ranges exceeding 100 km. They charge slower, but from a practical standpoint, you can just buy an extra 5 sets of batteries to cycle and it'll still be less than 30k euro recharging station for hydrogen. If we're talking swapping energy containers, then swapping batteries on most ebikes with removable batteries is also less than 2 minutes.

From a purely practical standpoint, we're actually closer to a standard in ebike batteries where you can just ship your bike to wherever you need, then rent charged batteries on-site, then swap them out for a fee for newly charged batteries at specific stations. In Japan, you could rent the entire ebike, run down the battery, bring it back to a station, then rent another bike with a fully charged battery.

 

[Deleted member 4210]

The 'charging ' station for hydrogen is simply compressed hydrogen gas being injected into a cylinder at very high pressure. Hydrogen can be a good energy carrier like electricity.

Hydrogen fueling stations have been around for decades. Just not in the abundance you would need to be practical. Usually we are talking about pressures of 5000 or 10000 psi, so plenty of energy can be stored. Then an on board fuel cell converts the hydrogen to electric without any combustion. Just a chemical reaction who's only emission is water vapor and air.

The hydrogen for these stations usually comes from reformed natural gas.

The first fuel cell used commercially was on the Apollo missions to supply power to the command module. Not only did it supply electric but also the drinking water for the crew. It was alkaline based. provided by United Technologies. They also worked with Hyundai to provide some of their early technology for hydrogen fueled fuel cell cars. And the first one was invented way back in the 1880's.

I worked at a company for 6 years that was involved in fuel cell R&D.

 

[Off road all day]

I love you Mike great info

 

[Ravi Kempaiah]

"One kilo of hydrogen is a source of 600 times more energy than a lithium battery of the same weight."

I think the dramatic difference in energy potential makes this technology worth pursuing. Economies of scale will bring the price down. The 30,000 euros was the cost for a commercial charger able to fill multiple vehicles during the day. The bike itself is 7,500 euros

"Already 100 complete Pragma Alpha bikes were sold during the last year to owners from France, Germany, Norway, the United States or Italy."

Obviously these customers must have a smaller charging station of some type and the company has been providing fuel cells to the military since 2004.

As proof of technology, this will work but I don't think this is going to get mainstream.
Many of my friends did their PhD fuel cells and some even work for companies like Nissan and Hyundai who are still working on this. We have had long discussion on the feasibility of seeing H2 powered vehicles.
The biggest stumbling block, as alluded in the lack of charging infrastructure and loss of efficiency at every stage.

One of the best explanation for this was given by Real Engineering and Engineering Explained channels. They have references for their analysis.

 

[Mr. Coffee]

"One kilo of hydrogen is a source of 600 times more energy than a lithium battery of the same weight."

That isn't a fair comparison.

One way to think of it is that at standard temperature and pressure, that one kilo of hydrogen will have a volume of approximately 12 cubic meters. Which won't exactly be aero. For a practical solution you will either need to store the hydrogen at high pressure (which will require a weighty steel pressure vessel and all of the hazards that would have), store it as liquid hydrogen (again you need a heavy insulated container, and will have to boil some of it off to keep it liquid (which means you can't leave it fueled for an indefinite period of time)), or store it as a metal hydride (very safe, very heavy, and you need to heat it to release the hydrogen).

Any of those practical solutions will end up weighing a lot more than one kilo. Especially for a small container I'd be the ratio of container to stored fuel would be fifty or one hundred to one.

You need to think of the weight of the system as much as the weight of the fuel. One other way to look at it is that batteries are basically pressurized containers for electrons. If you think of the electrons as containing the potential energy their energy to weight ratio would blow hydrogen (or any other chemical fuel) away.

What finally kills hydrogen for me is that when it burns in our atmosphere the flames are invisible.

I'm with Ravi. I can't see hydrogen going mainstream.

 

[indianajo]

Notice they didn't quote how many kilowatts the drive put out, or how heavy the bike was. The cost was E7500 without charger, a bit high I think.
My 1 kw conversion left cost $189 for the motor kit and $630 for a 100+ km battery with charger. Weighs about 70 lb with 100 kg cargo capacity plus 100 kg rider. With a 4 amp charger I built of $20 in parts charges in 4 1/4 hours.

 

[erider_61]

I just realized.. Why are we calling it an eBike? Isn't it an hBike?

The hydrogen is converted into electricity to run an ELECTRIC motor. Therefore it is an eBike...