Remind me, at what temperature does hydrogen liquefy?
In a typical tank size dewar, what sort of boil off rate would you expect?
I really don't think it is as portable, or safe, as diesel, or even petrol.
YMMV
About an accident every day on M4. Typically, three cars in the outer lane. What happens is that a car from middle lane turns into the outer lane with a smallish gap. The car in the outer lane then brakes a little to avoid the aggro. The car behind him, who was tailgating, can't slow down enough, then bang! Pushes the middle car into the first car just entered. Bonnets bent at an 90 deg angle, as they are designed to do. Some say to avoid capitations. People in tears. Usually very desirable new cars, now definitely looking second hand wear and tear...
Whilst this is true, the efficiency is starting to approach the efficiency of fossil fuels, end-to-end.
Plus, you can now generate it at the filling station - you no longer have to tanker it around the country.
It's usually clear leaving London. Where two lanes of the A4 turn into 3 of the M4. Coming into London, where the reverse happens, is frequently congested.
It's the perverse nature of motorway design. One would have thought that as the motorway approached the city it would be expected to carry more traffic, so its number of lanes should increase. This would also allow for more exit slips.
There was a plan some 40 odd years ago for an inner ring road 'motorway' in London, with all the existing ones extended to join up with it. Some bits of it were built. But of course all you'd do is move the congestion to a different place.
Hydrogen is the solution of the vested interests and captive market of oil cartels. They already make it on an industrial scale. Problem is the transport to and storage of it on unsecured sites in quantities that can fuel vehicles.
There are plans to supply Hydrogen to industrial users around Liverpool in place of NG - they don't know who will pay for all the new boilers but it won't be the industrial users. Also talking about dilution of NG with 20% Hydrogen for domestic supply but again they can't work out how to make them pay for the conversion. It would be like when NG replaced town gas, new re-sized gas jets would be needed in all appliances.
Electrolysis hydrogen filling stations put higher loads on the grid supply than an EV charging system. Because the amount of hydrogen stored is small ~3 cars fills, it will unlike a household overnight EV charge system put load on the grid during peak demand as it refills the store. This IS the national grid meltdown "scenario 1" where EV charging says F**K YOU and competes with peak demand for power. Home EV charge overnight on Eco 7 electricity is not going to overload the grid as it has about 7 GW of spare capacity overnight compared to daytime peak demand. It may create a slightly different power demand map requiring upgrade of some local supplies.
What they really doesn't want is propane/methane reformation, either in or off vehicle. No reason a methane reformer can't be run to fill a hydrogen fuel cell car at home from untaxed NG. If fuel cells / reformers that run on propane are developed a low cost infrastructure already exists that fills vehicle tanks with propane in 5min and has large safe 100+ vehicle fill capacity at each site.
Fuel cells don't have to have Hydrogen. For the last 5 years a friend has had a combined heat and power fuel cell on trial that uses methane from the mains NG gas supply. It's no bigger than a domestic central heating boiler.
(whoo at 13:00 on 24/1/18 gridwatch said UK was supplied by 19.7% wind and 18.7% solar. All of our reactors are running giving 20.7%. With hydro and pumped that was 60.7% zero emission power during winter. No hydrogen at all.)
Quite. In the UK, makes a lot of sense to use a gas powered power station to separate out hydrogen. Not.
Might be a very different matter where electricity comes totally from renewables. In the same way as it can make sense there to get drinking water from the sea.
On site production is very new technology. It's not perfect, but then mining lithium is far from perfect - and carrying half a tonne of batteries around is hardly efficient.
I don't understand the negativity shown towards hydrogen whilst people are getting evangelical about battery EV.
Tesla already have to charge batteries overnight to supply enough power to charge cars during the day - hydrogen isn't a million miles away from this concept. (The electrolysis runs until the on-site tank is full and the plant at Cobham can do 30 cars a day - not bad for the first install of its type in the country).
I'm not about either. LPG or compressed natural gas would make as much sense for a road vehicle as burning it in a power station to produce electricity to charge EVs. Or to produce hydrogen.
By all means do research into all available technologies. But not just jump on the latest bandwagon. Which is usually from business seeking to make money from it.
My employers are looking at everything - LPG powered REx PHEVs, battery EV, fuel cell EV and GTL diesel substitutes.
We are only at the start of the energy transition journey - and the next big 'dieselgate' will be focused on the environmental damage being done mining Lithium for batteries. (Although environmentalists and goverments don't seem to worry about damage being done in 3rd world countries).
Lithium is in abundance, it's rare earth metals used for magnets that will be the issue.
Currently the only economic mining of neodymium is in China. I wonder which green pressure groups the Chinese fund?
In abundance in 3rd world countries where we don't care about the damage done to either the landscape or the health of the workforce mining it.
But it's only a few brown children being sacrificed so the wealthy Westerners can pretend they care about the environment...
It might have slipped your attention, but we have no control over those countries and what they do. We cannot police every f****ng thing the world over! It's none of our business to do so anyway.
We do have control. We can refuse to buy their products until they adopt ethical and environmental standards. This isn't 'policing', it's exercising choice.
But that would push up the cost of this month's fashion trinket, so we won't.
Of course the UK has a choice - we could refuse to buy the stuff unless it's mined according to certain standards.
Are you thinking of cryogenic tanks, or room temperature ones? I agree that the latter could be readily swappable, given a standardised car design and suitable mechanical handling kit, but the weight of a steel pressure vessel will destroy the energy/weight factor, and I doubt if carbon fibre vessels would recover it.
I can only see hydrogen working with cryo storage and cryo tanks built into the car. And likely to take some time to implement.
or more likely nuclear
"The Mirai has two hydrogen tanks with a three-layer structure made of carbon fiber-reinforced plastic consisting of nylon 6 from Ube Industries[42] and other materials. The tanks store hydrogen at 70 MPa (10,000 psi). The tanks have a combined weight 87.5 kg (193 lb).[2][38] and
5 kg capacity."(though the tank is probably more swappable than the battery in an EV, where sometimes the battery /is/ the chassis. The Model S battery is swappable, though)
Theo
Because the poster that I was responding to said "suitable tanks which could be swapped in/out of cars"
Really?
Self verified calculation, but I reckon for 400 square metres of solar panels, using the June daily average insolation value for optimal orientation from here for south east England of 4.6 kWh/square metre
Using another source
that says that a hectare of solar panels gives 1 MW, a fuel station backed by a hectare of land would provide about 450 gallons of petrol/diesel per day.
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