Cycling UK Forum

Seems like there has been an advance in hyrdogen fuel cells. The problem has always been safe storeage of the hyrogen. It seems it has been cracked.

It seems that such powers sources are the most efficient around

Hydrogen generates three times as much power per kilogram compared to fossil fuels - approximately 39.0 Kilowatt hours per kilogram compared with roughly 13 KWh per kg for kerosene or petrol or just 0.2 KhW for conventional lithium ion batteries.

it dont take much imagination to see the multiplicity of applications from cars to ebikes where the batterys are what make them so heavy?

Here it is being used for a drone.
https://www.bbc.co.uk/news/technology-50841104

so the future looks bright with renewable energy sources being used to make hydrogen from water to power various vehicles? And Iran and Saudi can sink back into the medieval era where they belong and not affect the civilised world any more?

mercalia wrote:And Iran and Saudi can sink back into the medieval era where they belong and not affect the civilised world any more?

I think you'll find that Iran is the source of much our civilised world.

mercalia wrote:It seems that such powers sources are the most efficient around

Depends where you get your hydrogen.
If you get it from electricity then it's not even close.

On the plus side it means cars can get bigger, faster and heavier since they won't need to worry about battery weight.

Where is the civilised world?

horizon wrote:

mercalia wrote:And Iran and Saudi can sink back into the medieval era where they belong and not affect the civilised world any more?

I think you'll find that Iran is the source of much our civilised world.

hmm 2000+ years ago maybe? Then it was Persia? Not much since?

kwackers wrote:

mercalia wrote:It seems that such powers sources are the most efficient around

Depends where you get your hydrogen.
If you get it from electricity then it's not even close.

On the plus side it means cars can get bigger, faster and heavier since they won't need to worry about battery weight.

yes but with renewables -> electricity on the increase one can hope? in fact it might be just the spur to increase such sources that is needed, since it would then complete the circle - at the moment we need petrol and diesel and other means are no good viz lithium cells?

mercalia wrote:So the future looks bright with renewable energy sources ... Iran and Saudi can sink back into the medieval era where they belong and not affect the civilised world any more?

I note that the inventor hails from Palestine. Would that be part of your civilised world?

It requires 50kW of energy to create 1kg of hydrogen.

So its still requires more energy to make than it produces

Oldjohnw wrote:Where is the civilised world?

In the White House?????????????

mercalia wrote:yes but with renewables -> electricity on the increase one can hope? in fact it might be just the spur to increase such sources that is needed, since it would then complete the circle - at the moment we need petrol and diesel and other means are no good viz lithium cells?

I think we're in Tomorrows World territory here, tbh I wouldn't feel I could make a confident prediction.

Yes, there's going to be a lot more electricity and a lot of that will be from renewables so storing it will be key.
But the lecky->hydrogen->lecky cycle isn't particularly efficient so you're going to need a *lot* more generation than you otherwise would and against this we're fast approaching an EV tipping point which in itself will create pressures on supply without the extra capacity to cover an inefficient process.

Then there are the issues with using hydrogen. It's a quite tricky element, even if you've fixed storage issues then at some point it becomes a gas again and almost everything in contact with it has problems.

Against this you've got the onward march of battery tech. Who knows how much better they'll get? Tesla is claiming they'll have batteries that will last a million miles in an EV and already they pretty much have batteries that will outlast the car.
Throw in the relentless march of efficiency, energy density, ease of recycling and the moving away from hard to source materials and I think predictions become a lot harder.

The only thing you can say with any certainty is that in 10 years time energy storage will be a lot better than it is today.

EV uses like cars and Tesla for instance is a lot different them in ebike use so they can manage the longer cell life.
Some cells used are only designed and made for them never being released to the mass market.
Cooling and heating is used to keep the mass of battery cells at a more stable operating temperature during charge/discharge stages and the fact that they don't utilise the full voltage charge but restricting the charge to balance at 4.05v - 4.1v.

I've been driving around in EVs since 2015, have to say am surprised to see a topic on hydrogen fuel cells on a bike forum, though it's a common topic in EV discussion

Hydrogen is absolutely pointless for personal transportation even in a car letalone a pedal bike. On a pedal bike I cannot see may people needing more than 0.5kWh max, given how efficient bikes are compared to cars.

The BMS/motor system on an eBike must weigh a fair amount compared to the battery. Get those weights down and the need to really improve cell density chemistry is not really needed.

Tesla runs some of the dense cell chemistry been mass produced today, but that isn't without problems, mainly fires.

https://www.businessinsider.com/why-tes ... ire-2019-4

The chemistry Tesla run in their packs is so unstable our car (Tesla Model X) never really 'shuts off', even when 'off' the BMS remains on constantly monitoring cell balance and looking for thermal runaway. Its why Tesla cars all suffer 'vampire' drain, where even left parked up the battery charge status drops by 0.5-1% a day as the BMS is using up energy. Versus something like a Nissan Leaf which you can park up leave for 6 months and return with essentially the same amount of charge.

The denser the pack, the more aggressive the chemistry the more you have to monitor. On a car the argument for advanced BMS to allow for high battery densities make sense, but on a pedal bike I would have thought stable, safe chemistry is by far the best option. Especially given the small amount of cells involved.

heh heh.. just have a looksee when you are next in a long stay park at Heathrow or B'Ham airports watch the dudes walking around with battery packs on carts boosting flat batteries on high and low end motors.. used to be only BM'S .. but Vampire drain has affected most cars for years and years ever since they started relying on computers. read a blog from a similar long term user of EV last evening where he reckoned there was no joined up thinking coming out of Westminster [how could there ever be] and that 10 years or less down the road projected by BJ all electric cars [no hybrids ]will if all switched on to charge at the same time any nite would collapse the available grid... and that at least 5 /7 more powerstations are needed and they can take up to 25 years to get up and running, so we are in for a mini stone age if Westminster gets its way, a good job then that us on here can use bikes for transport... God Bless all here and God help the rest of you.. will

The whole grid collapsing worry is a myth, 100%.

Forget everything else, if you consider peak uk grid demand, which is about 5-8pm, and the stories about how at break time for Coronation street the grid has to pull in more supply to meet demand.

This is certainly true, below is our house hold (5 bed detached) electricity use over 24hrs, ignore the high use overnight thats the EV charging, but you can see a clear spike in demand of over 3KW at 8pm, which every household in the UK will have.

*Note we do have solar Panels hence electricity demand from the grid is 0KW during day light hours.



However we now have a home battery fitted, which stores enough electricity to mean we now pull 0KW from the grid from the hours of 8am to 1am next day.

Now if everyone did what we did than grid demand at 1am will go nuts, but you don't need everyone to do that. Even if a small percentage of people shifted their electricity consumption from grid usage at peak times to off peak than EV charging will not put that much strain on the grid.

Thinks of it like traffic in school holidays, just taking a small number cars out of the congestion equation really reduces strain on the network. Grid balancing with battery storage is the future. And ofcourse I hope to reduce our overall electricity use even more with an EV pedal machine than a car .

Dear God, and you're hoping fervently like all the rest of the morons in charge that you will change peoples habits overnight or even over a few years ask a few wives how that works.. divorce usually... and those in power or who thought they were.... tried to change things for their ideas over the past 4 years ... and what a horlix that was.. we aren't germans or japanese.. water doesn't run uphill.... will