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Other Hondas & General Topics => Off Topic (Non-Honda) => Topic started by: MartinJG on August 08, 2021, 10:29:27 PM
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This is interesting.
No mention of the high cost of producing hydrogen via hydrolysis. Crack that and it is game on.
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This is interesting.
No mention of the high cost of producing hydrogen via hydrolysis. Crack that and it is game on.
That's the easy bit. All you need is electricity.
They're already doing it in Orkney and Shetland.
https://www.bbc.com/future/article/20190327-the-tiny-islands-leading-the-way-in-hydrogen-power
https://www.shetland.org/blog/green-hydrogen-potential
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Hydrogen's a great idea and I really hope it takes off, well done Scotland for pioneering it.
But there're a lot of hurdles yet in scaling it up. Only 5% of the world's H2 production comes from electrolysis at present, the rest comes from fossil fuels. The most common process (steam reforming of methane) creates around 9-12 tons of CO2 for every ton of H2.
https://en.wikipedia.org/wiki/Hydrogen_production
So you either have to massively increase the amount of generating capacity even to meet the current demand, never mind any future demand as H2 usage increases, or you have to keep extracting the fossil fuels and have very large scale carbon capture and storage (CCS). At least the CCS problem is easier if it's captured at source rather than pumped out of the tailpipes of vehicles.
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My simplistic understanding of converting Hydrogen through hydrolysis is that it has been traditionally hampered by the fact that it uses almost as much energy to convert. However, it seems to me the key here is untapped solar energy. Plenty of that for now subject to the usual constraints/braindead politics and power games. This effectively bridges the problem of storage with existing battery technology. There is the issue of storage under pressure which is potentially dangerous, however, even there, I believe the faster rate of dispersion of hydrogen into the atmosphere is less of a risk than petroleum gas (LPG) etc.
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Hydrogen's a great idea and I really hope it takes off, well done Scotland for pioneering it.
But there're a lot of hurdles yet in scaling it up. Only 5% of the world's H2 production comes from electrolysis at present, the rest comes from fossil fuels. The most common process (steam reforming of methane) creates around 9-12 tons of CO2 for every ton of H2.
https://en.wikipedia.org/wiki/Hydrogen_production
So you either have to massively increase the amount of generating capacity even to meet the current demand, never mind any future demand as H2 usage increases, or you have to keep extracting the fossil fuels and have very large scale carbon capture and storage (CCS). At least the CCS problem is easier if it's captured at source rather than pumped out of the tailpipes of vehicles.
Spot on. It needs an excess of electrical energy.
Generating hydrogen by electrolysis requires a lot of energy to break hydrogen-oxygen bonds.
Generating hydrogen from hydrocarbons requires slightly less energy to break carbon to hydrogen bonds which is partially offset by the energy obtained by making carbon to oxygen bonds but results in the formation of carbon dioxide.
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Hydrogen's a great idea and I really hope it takes off, well done Scotland for pioneering it.
Hydrogen will take off if you fill a big balloon with it ;D
Hydrogen is not a fuel per se, it is an energy carrier, it takes a lot more energy input to make it than you get back. looking at USA a bloke from MIT says he gets 65 flat highway miles per 1 Kg of hydrogen from his Toyota Mirai ( hydrogen fuel cell ), but to make 1kg of hydrogen takes about 48kw/ hours of electricity. the average range of a battery EV is about 25kw/ h per 100 miles ( under ideal conditions in summer on flat road - 24kw Nissan leaf did about 70 miles in real world ). So already hydrogen fuel cell requires much more primary energy than a normal battery car. The fuel cell requires about 80Kw/h of primary energy input to cover 100 miles., and that is without the energy required to compress and transport it.
Solar power not really reliable in UK ( very little October to March ) so would we become reliant on sunny middle east for our energy once again ?
https://www.toyota.co.uk/new-cars/new-mirai/meet-mirai#1
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Hydrogen's a great idea and I really hope it takes off, well done Scotland for pioneering it.
Hydrogen will take off if you fill a big balloon with it ;D
Hydrogen is not a fuel per se, it is an energy carrier, it takes a lot more energy input to make it than you get back. looking at USA a bloke from MIT says he gets 65 flat highway miles per 1 Kg of hydrogen from his Toyota Mirai ( hydrogen fuel cell ), but to make 1kg of hydrogen takes about 48kw/ hours of electricity. the average range of a battery EV is about 25kw/ h per 100 miles ( under ideal conditions in summer on flat road - 24kw Nissan leaf did about 70 miles in real world ). So already hydrogen fuel cell requires much more primary energy than a normal battery car. The fuel cell requires about 80Kw/h of primary energy input to cover 100 miles., and that is without the energy required to compress and transport it.
Solar power not really reliable in UK ( very little October to March ) so would we become reliant on sunny middle east for our energy once again ?
https://www.toyota.co.uk/new-cars/new-mirai/meet-mirai#1
Indeed, hence my caveat regarding politics/power games and storage for transport around the world etc. I know there is also one small fly in the ointment. Nox is a by product of hydrogen combustion which of course is the nemesis of heavy oil.
PS - The law of conservation of energy springs to mind regarding your point on H being a carrier. 'The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another'. Despite all the bull surrounding energy, some things never change :).
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Orkney is having to produce Hydrogen as they have so much tidal generated electricity they cannot use it. The cables to mainland Scotland are too feeble to export it.
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Hydrogen's a great idea and I really hope it takes off, well done Scotland for pioneering it.
Hydrogen will take off if you fill a big balloon with it ;D
Hydrogen is not a fuel per se, it is an energy carrier,
Correct. Hydrogen can be regarded as an energy storage system[
it takes a lot more energy input to make it than you get back.
Not so. A conventional ICE engine has an efficiency of the order of 20%. Using hydrogen as a fuel in a fuel cell is approximately twice as efficient.
https://afdc.energy.gov/fuels/hydrogen_basics.html
https://www.viessmann.co.uk/heating-advice/how-efficient-are-hydrogen-fuel-cells#:~:text=According%20to%20the%20US%20Department%20of%20Energy%20Hydrogen,as%20the%20kinds%20of%20roads%20being%20driven%20on.
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'The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another'. Despite all the bull surrounding energy, some things never change :).
Thermodynamics has nothing to do with politics.
Ye cannae change the laws o' thermodynamics cap'n
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Modern petrol engines about 35% efficiency, modern diesels about 45%.
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The near term future for Hydrogen is less likely t be in vehicles and more likely to be in domestic heating and cooking. Hydrogen produced by renewable energy (e.g. wave and wind in the Orkneys) can be used as a means of storing this renewable energy for future use. Here in the UK there are several things going on looking at hydrogen. I could have sworn I saw on the BBC a story about the Northern Gas Networks trial in the North East. Can't find the story but here is a link to NGN's own item on it...
https://www.northerngasnetworks.co.uk/2021/07/23/green-light-for-first-hydrogen-blending-on-a-public-gas-network/
...and here is link to a BBC story on a plan to produce hydrogen from solar in Dorset...
https://www.bbc.co.uk/news/uk-england-dorset-57986600
Some people will find a 100 reasons why something can't be done but never propose an alternative other than keep doing what we have always done and hope for the best. Thankfully, there are people, scientists and engineers, who strive for a better way.
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The efficiencies being offered for IC engines is the maximum, however it varies enormously with different speed and load. At idle (doing no useful work) the efficiency is by definition zero. The real downside of an ICE is that it typically spends a lot of time running at very low efficiency. Engineering of an ICE system can make it work at more efficient regions for more of the time (downsizing, high gear ratios, different operating cycles to reduce pumping losses for example). A best BSFC of 250g/kWhr equates to around 34% thermal efficiency for a petrol engine, but off the optimum speed/load point a BSFC of 350g/kWhr is only 24%. In the attached image, running at 1500rpm and 1.5Bar BMEP (around 20Nm in that engine) it's more like 450g/kWhr and 18%.
(https://michaelsoroka.files.wordpress.com/2014/09/saturn-bsfc-map.jpg?w=792)
A fuel cell or battery motor system doesn't suffer this very poor efficiency at light load/low speed which is typical of a ICE.
Storing energy in any form takes more input than you get back out again (entropy increases - law of thermodynamics - can't be avoided), think of it as thermodynamic friction. Doing it in some forms means a much bigger entropy increase (lower efficiency) than for other forms. Charging a battery produces heat and thus losses, you don't get out as many kWhrs as you put in. Producing free hydrogen from a compound takes energy. The trick is to use a storage and recovery system which is reasonably efficient and practically executable in the real world. Stored energy density, kWhr/kg and kWhr/litre volume, are both significant for any mobile (vehicle) system, but might not be as important for a static system (generating mains electricity etc). $/kWhr is the final deciding factor.
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The efficiencies being offered for IC engines is the maximum, however it varies enormously with different speed and load. At idle (doing no useful work) the efficiency is by definition zero.
Which is why one of the objectives of Honda's eHEV system is to keep the engine running in the most efficient zone and not idle doing nothing useful (unfortunately, the vehicle designers didn't address the problem of the engine running to provide cabin heating during cold weather).
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Modern petrol engines about 35% efficiency, modern diesels about 45%.
I suppose it was an American site and comparing it to gas guzzler ICEs
I was being conservative (with a small c) in using the double figure.
"The interest in hydrogen as an alternative transportation fuel stems from its ability to power fuel cells in zero-emission FCEVs, its potential for domestic production, its fast filling time, and the fuel cell's high efficiency. In fact, a fuel cell coupled with an electric motor is two to three times more efficient than an internal combustion engine running on gasoline."
"According to the US Department of Energy Hydrogen Program, a standard fuel car with a combustion engine runs at around 20 per cent efficiency, whereas vehicles that run using hydrogen fuel cells are around 40 to 60 per cent efficient. This number could vary depending on the size and weight of the car, as well as the kinds of roads being driven on.
https://afdc.energy.gov/fuels/hydrogen_basics.html
"The department goes on to state that the maximum efficiency that a combustion engine could achieve is around 58 per cent, however fuel cells have a theoretical maximum efficiency of 85 to 90 per cent. This depends on how the fuel cell is being used and is usually unachievable in real world applications. "
https://www.viessmann.co.uk/heating-advice/how-efficient-are-hydrogen-fuel-cells#:~:text=According%20to%20the%20US%20Department%20of%20Energy%20Hydrogen,as%20the%20kinds%20of%20roads%20being%20driven%20on
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I thought this was quite an interesting program from BBC World Service: https://www.bbc.co.uk/programmes/w3ct1hsk (https://www.bbc.co.uk/programmes/w3ct1hsk)
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The near term future for Hydrogen is less likely t be in vehicles and more likely to be in domestic heating and cooking.
Yes I think that in the choice between electric and hydrogen powered vehicles, EVs will win out at least with cars.
with HGVs I would hope hydrogen would take over from diesel until battery power/ weight ratio is improved.
I was talking to my plumber when my boiler was serviced last year and he was an advocate of hydrogen rather than heat pumps.
I don't know how much modification the gas network would need to adapt to hydrogen rather than natural gas. There is a trial in Fife as well.
https://www.theguardian.com/environment/2020/nov/30/scottish-green-hydrogen-fife
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https://www.energy.gov/eere/fuelcells/hydrogen-storage-challenges
Hydrogen has very small molecule size, and leaks very easily. Normal gas mains for Natural gas would need to be improved. Hydrogen has no smell so like natural gas a smell may have to be added for humans to notice a leak.
A plumber / gas tech would most likely favour hydrogen, it would mean minimal change to his job and very little re-training needed. It would undoubtedly be a lot cheaper to go the hydrogen route for domestic as the outlay for heatpumps and the changes needed for present radiator sizing to work at much lower temperatures and larger bore pipes etc. Oh and another thing, the colder the ambient temp gets the less output you get from heatpumps ( like majority of renewables it produces the least when you need it the most ).
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https://www.energy.gov/eere/fuelcells/hydrogen-storage-challenges
Hydrogen has very small molecule size, and leaks very easily. Normal gas mains for Natural gas would need to be improved. Hydrogen has no smell so like natural gas a smell may have to be added for humans to notice a leak.
A plumber / gas tech would most likely favour hydrogen, it would mean minimal change to his job and very little re-training needed. It would undoubtedly be a lot cheaper to go the hydrogen route for domestic as the outlay for heatpumps and the changes needed for present radiator sizing to work at much lower temperatures and larger bore pipes etc. Oh and another thing, the colder the ambient temp gets the less output you get from heatpumps ( like majority of renewables it produces the least when you need it the most ).
You should read the link I provided earlier. Answers most of your questions/assumptions. The hydrogen/natural gas blend is perfectly within the design tolerances of existing equipment and infrastructure across the UK. If adopted nationally, the saving on CO2 emissions has been estimated as the equivalent of taking 2.5m cars off the road.
https://www.northerngasnetworks.co.uk/2021/07/23/green-light-for-first-hydrogen-blending-on-a-public-gas-network/
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..... If adopted nationally, the saving on CO2 emissions has been estimated as the equivalent of taking 2.5m cars off the road.
https://www.northerngasnetworks.co.uk/2021/07/23/green-light-for-first-hydrogen-blending-on-a-public-gas-network/
I appreciate it isn't an in-depth article, but I'm not clear whether that saving comparison takes into account the production of the hydrogen or just a simple gas point-of-use calculation. If the hydrogen can be supplied with minimal CO2 output in the process, then it would certainly be a worthwhile exercise, however the devil is always in the detail.
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..... If adopted nationally, the saving on CO2 emissions has been estimated as the equivalent of taking 2.5m cars off the road.
https://www.northerngasnetworks.co.uk/2021/07/23/green-light-for-first-hydrogen-blending-on-a-public-gas-network/
I appreciate it isn't an in-depth article, but I'm not clear whether that saving comparison takes into account the production of the hydrogen or just a simple gas point-of-use calculation. If the hydrogen can be supplied with minimal CO2 output in the process, then it would certainly be a worthwhile exercise, however the devil is always in the detail.
I was pleasantly surprised to see that the article on the Fife trial specified it was to be based on green hydrogen from renewables.
I expected it to be grey( made from hydrocarbons) hydrogen made in Mossmorran.
https://www.theguardian.com/environment/2020/nov/30/scottish-green-hydrogen-fife
I would think that in the example from Gateshead the savings in carbon dioxide would only be made if green hydrogen is used.
https://www.weforum.org/agenda/2021/07/clean-energy-green-hydrogen/
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..... If adopted nationally, the saving on CO2 emissions has been estimated as the equivalent of taking 2.5m cars off the road.
https://www.northerngasnetworks.co.uk/2021/07/23/green-light-for-first-hydrogen-blending-on-a-public-gas-network/
I appreciate it isn't an in-depth article, but I'm not clear whether that saving comparison takes into account the production of the hydrogen or just a simple gas point-of-use calculation. If the hydrogen can be supplied with minimal CO2 output in the process, then it would certainly be a worthwhile exercise, however the devil is always in the detail.
That article reads as if it’s simply a trial to establish whether the transmission network and the end-user devices can cope with a hydrogen blend, which seems like a useful thing to check before going whole-hog for H2. They don’t need to worry about the source of the hydrogen to do that. If they were genuinely using green hydrogen (from renewable resources) as opposed to blue (from fossil fuels) you’d expect them to trumpet that, but they don’t even mention it. There won’t be any CO2 saving unless the source is renewable ... if not, you might as well keep burning the natural gas without going through the faff of turning it into hydrogen first.
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..... If adopted nationally, the saving on CO2 emissions has been estimated as the equivalent of taking 2.5m cars off the road.
https://www.northerngasnetworks.co.uk/2021/07/23/green-light-for-first-hydrogen-blending-on-a-public-gas-network/
I appreciate it isn't an in-depth article, but I'm not clear whether that saving comparison takes into account the production of the hydrogen or just a simple gas point-of-use calculation. If the hydrogen can be supplied with minimal CO2 output in the process, then it would certainly be a worthwhile exercise, however the devil is always in the detail.
That article reads as if it’s simply a trial to establish whether the transmission network and the end-user devices can cope with a hydrogen blend, which seems like a useful thing to check before going whole-hog for H2. They don’t need to worry about the source of the hydrogen to do that. If they were genuinely using green hydrogen (from renewable resources) as opposed to blue (from fossil fuels) you’d expect them to trumpet that, but they don’t even mention it. There won’t be any CO2 saving unless the source is renewable ... if not, you might as well keep burning the natural gas without going through the faff of turning it into hydrogen first.
Absolutely.
It was the reference to the 2.5M cars being taken off the roads in the quick facts at the end of the article picked up by Richard Frost and then Embee, I was referring to. It would have to be green hydrogen to make that saving.
Seems like there are Forty Shades of Green or is it Fifty Shades of Grey
https://www.weforum.org/agenda/2021/07/clean-energy-green-hydrogen/
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They don’t need to worry about the source of the hydrogen to do that. If they were genuinely using green hydrogen (from renewable resources) as opposed to blue (from fossil fuels) you’d expect them to trumpet that, but they don’t even mention it. There won’t be any CO2 saving unless the source is renewable ... if not, you might as well keep burning the natural gas without going through the faff of turning it into hydrogen first.
Absolutely, it's a trial of the Hydrogen infrastructure (transmission, domestic and industrial equipment), not of the creation of it. By the way, Hydrogen isn't made from natural gas, that would be daft as you say. It was made from coal, hence it was called coal gas, or town gas, as it could be made locally in towns, prior to the creation of the gas national grid. The hydrogen/natural gas blend was in use prior to the conversion to natural gas and is still in use in Europe.
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They don’t need to worry about the source of the hydrogen to do that. If they were genuinely using green hydrogen (from renewable resources) as opposed to blue (from fossil fuels) you’d expect them to trumpet that, but they don’t even mention it. There won’t be any CO2 saving unless the source is renewable ... if not, you might as well keep burning the natural gas without going through the faff of turning it into hydrogen first.
By the way, Hydrogen isn't made from natural gas, that would be daft as you say. It was made from coal, hence it was called coal gas, or town gas, as it could be made locally in towns, prior to the creation of the gas national grid. The hydrogen/natural gas blend was in use prior to the conversion to natural gas and is still in use in Europe.
That was years ago before North sea oil and gas. As you say the old town gas used to contain about 50% hydrogen but much of industrial hydrogen is manufactured from hydrocarbons now.
https://en.wikipedia.org/wiki/Hydrogen_production
https://royalsociety.org/topics-policy/projects/low-carbon-energy-programme/hydrogen-production/
Edit substituted "hydrocarbons" for "petrochemicals" and added Wikipedia link
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https://www.energy.gov/eere/fuelcells/hydrogen-storage-challenges
A plumber / gas tech would most likely favour hydrogen, it would mean minimal change to his job and very little re-training needed. It would undoubtedly be a lot cheaper to go the hydrogen route for domestic as the outlay for heatpumps and the changes needed for present radiator sizing to work at much lower temperatures and larger bore pipes etc. Oh and another thing, the colder the ambient temp gets the less output you get from heatpumps ( like majority of renewables it produces the least when you need it the most ).
Pros and cons (mostly cons) for heat pumps.
Pros and cons (mostly pros) for hydrogen boilers
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If we get the 40GW of unreliable wind generation that the government proposes then hydrogen production will be one way of absorbing the excess electricity which arises when the wind does blow (perhaps 1/3rd of the time).
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If we get the 40GW of unreliable wind generation that the government proposes then hydrogen production will be one way of absorbing the excess electricity which arises when the wind does blow (perhaps 1/3rd of the time).
Hopefully there will be other renewables being developed like tidal, waves and geothermal.
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I don't know why more money is not being spent (private and government) on developing Tidal Generators further. What has been done shows how well tidal slots into the "Renewables" basket.
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I don't know why more money is not being spent (private and government) on developing Tidal Generators further. What has been done shows how well tidal slots into the "Renewables" basket.
Yep . Tidal not intermittent like solar or wind.
Very powerful tidal races round Western Isles and Moray Firth.
Slower dependable tides all round country.
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I don't know why more money is not being spent (private and government) on developing Tidal Generators further. What has been done shows how well tidal slots into the "Renewables" basket.
There's currently no penalty for unreliability applied to the pricing of energy to reflect the need to have back-up sources available. Doing this would make the nominally more expensive but more reliable types of renewables more attractive (and also push up the cost of electricity which will have to happen although no gov't will want to admit it).
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Yesterday evening I red a recent article about energy production costs composed by experts of couple of Finnish universities. They ended up to conclusion that among the renewable energy sources nuclear energy is still the most economical clean energy in long run despite of the very high construction and decommissioning costs.
In British conditions I would assume tidal and off-shore wind energy to come close. But then there are these aspects other than economics: wind power spoils the landscape tens of miles away and some people are scared by nuclear power.
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Before moving I lived surrounded by wind farms and I never thought they detracted from the landscape. I rather like them.
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50 years ago, I worked in the nuclear industry. The UK were leading the world in reactor development but scare mongering and misinformation consigned it to the dustbin. About 19% of our power is still being generated by nuclear power but this is due to be halved in the next four years.
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Currently about 28% of the Finnish energy production is coming from nuclear plants (four reactors currently), but it will increase to 40% next year when a new plant (fifth reactor) starts full scale operation. I'm looking forward to next new plant (sixth reactor), which is likely to start production around 2030.
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50 years ago, I worked in the nuclear industry. The UK were leading the world in reactor development but scare mongering and misinformation consigned it to the dustbin. About 19% of our power is still being generated by nuclear power but this is due to be halved in the next four years.
What's happening to Hinkley Point?
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What's happening to Hinkley Point?
Who knows, but even that is being supplied by the Chinese and French >:(
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The Toyota Mirai sell for € 85.990 new here in Belgium. Second hand however the prices dropped dramatically. A 2022 model you can buy below 20K€. Unfortunately the infrastructure in Europe is shrinking instead of expanding