diesel was the future....of course, 20 years on, that was a mistake
Please do tell us what you think the unknown potential consequences for the environment that the dangerous byproduct of burning hydrogen called "water" might be......
The UK government looks set to delay the publication of its much-anticipated Hydrogen Strategy, Kwasi Kwarteng, Secretary of State for Business, Energy and Industrial Strategy (BEIS), told MPs this morning. The milestone report – which is due to outline the government's goals for a hydrogen economy and how it can decarbonise …
Depends on what you burn it in. In pure O₂ you indeed get water, but diesel only produces the NOx pollutants because it's burnt in air, which is 78% nitrogen. Burn H₂ in air and you'll get other combustion byproducts, especially since it burns very hot. Burning it in a fuel cell will be better, of course.
Not helped by the diesel car manufacturers rigging their engine management systems to beat the emissions tests, and the various European governments (UK included) not noticing that the air pollution measurements did not match up with the supposed cleaner emissions produced by the vehicles on the roads (or ignored the mismatch).
One of the problems with hydrogen is that it does tend to invade metals. Attempts to create really high vacuum chambers are beset by the problems of lighter elements penetrating the vessel walls and being liberated when the air is removed.
"At room temperature, hydrogen atoms can be absorbed by carbon steel alloys. The absorbed hydrogen may be present either as atomic or molecular form. Given enough time, the hydrogen diffuses to the metal grain boundaries and forms bubbles at the metal grain boundaries. These bubbles exert pressure on the metal grains. The pressure can increase to levels where the metal has reduced ductility and strength."
Of course all you have to do then is keep your hydrogen cylinder well below 'room temperature', but that requires cooling and energy.
The silly thing is, of course, that even with VAG cheating on their emissions, the total amount of NOx and particulates has not gone up, it's just not gone down as much as we expected.
If you check out graphs based in the 70's you'll see that the air in our cities has never been cleaner. I suspect due to a large degree on the replacement of ageing HGV and bus engines with Euro-6 compliant ones. (Stood round the back of a new bus recently? It doesn't stink nearly as bad as it used to).
The recent alarms on air quality is because the limits have been going down faster than engines can improve.
...by some measures, Diesel is cleaner than petrol, even if by others it isn't, so a higher proportion of Diesel-engined cars since the 1970s - when nearly all cars were Petrol-powered - will make a difference. Certainly in the 1990s, improvements in Diesel technology were outpacing improvements in petrol technology, but it was starting from a fairly low base.
From a UK point-of-view, don't forget the Clean Air Act which removed coal- and wood-burning fires from many cities and towns in the 1960s, the removal of pollutants such as Sulphur and Lead from fuels in the 1970s and 1980s and the closure of much heavy industry, some of which was based in or around towns and will have contributed to poor air quality in those towns. These things would have made big improvements to local air pollution, even if the engines themselves hadn't become much more efficient - which of course they have.
For example, within a three mile radius of the centre of Caerphilly - a town essentially built in a basin (a bit like a small Sheffield, with similar odd localised weather), in the mid 20th-century there were five major coal mines, two of which had coking plants, a town-gas plant, a railway maintenance shed, an aero-engine maintenance factory, a tar plant, a couple of quarries and probably half a dozen other things I've forgotten. Products for these were mainly shipped by rail, steam-powered until the 1960s, or by heavy dirty-Diesel lorries.
The air (and other) pollution from these would have peaked mid-century, and only really begun to decline in the 1970s as first the railway shed was closed (mid 1960s), the gas plant went (North Sea Gas), then the coking plants and the coal mines. The last of these mines didn't close until the mid 1980s.
The one area where many cities went backwards in the 1960s and 1970s was local public transport, removing "clean at the point of use" electric trams and trolleybusses in favour of Diesel-powered vehicles.
It all makes a difference!
It releases dihydrogen monoxide, a constituent of many known toxic substances, diseases and disease-causing agents, environmental hazards and can even be lethal to humans in quantities as small as a thimbleful.
Some of the known perils of Dihydrogen Monoxide are:
- Death due to accidental inhalation of dihydrogen monoxide, even in small quantities.
- Prolonged exposure to solid dihydrogen monoxide causes severe tissue damage.
- Excessive ingestion produces a number of unpleasant though not typically life-threatening side-effects.
- dihydrogen monoxide is a major component of acid rain.
- Gaseous dihydrogen monoxide can cause severe burns.
- Contributes to soil erosion.
- Leads to corrosion and oxidation of many metals.
- Contamination of electrical systems often causes short-circuits.
- Exposure decreases effectiveness of automobile brakes.
- Found in biopsies of pre-cancerous tumors and lesions.
- Given to vicious dogs involved in recent deadly attacks.
- Often associated with killer cyclones in the U.S. Midwest and elsewhere, and in hurricanes including - deadly storms in Florida, New Orleans and other areas of the southeastern U.S.
- Thermal variations in dihydrogen monoxide are a suspected contributor to the El Nino weather effect.
And I could go on.
But seriously, the problem isn't so much the emissions, it is the way the hydrogen is produced, and the fact that it is near-impossible to store the stuff, because it will escape through the tiniest of gaps.
While he spoke about the importance of hydrogen, he also struck a note of caution that it was not the "panacea" some believe.
If we don't get hydrogen from gas and releasing CO2 at the same time, where do we get it from. Wind power?
We have 24GW of installed wind power. So far this month electricity demand has averaged just under 29GW so on paper perhaps we will soon have green electricity to spare? Sadly not in practice. So far this month wind power has averaged less than 2.5GW. Gas and coal (yes we are still burring a little coal in July) together have averaged over 12GW so far this month. There is a way to go before we can stop burning coal let alone gas, and a mountain to climb before we have enough excess capacity to start using it to make hydrogen.
Nuclear cogeneration would definitely be a majorly beneficial source, seeing as it can be done concurrently with electricity production.
Related report for those interested - Missing Link to a Liveable Climate: How Hydrogen-Enabled Synthetic Fuels Can Help Deliver the Paris Goals. Pg 55 gives a good indication of the spatial requirements for the predicted amount of energy.
Where's solar in your figures? Also, if eg modes of transport use hydrogen rather then electricity then that's extra capacity the answer will be solar/wind powered hydrolysis of water with far better catalysts. Such as the proposed blue hydrogen harbour project. The efficiency of hydrogen production from water is getting better annually. Extracting from natural gas, whilst cheaper, is a no no environmentally.
Is a hydrogen tank a better store of energy than a lithium ion battery?
If you look at the energy density in MJ/kg, and ignore the weight of the tank, then hydrogen looks very good. In MJ/L, the energy density is about double, but an electric motor would be a lot more efficient at turning it into movement - about 2 - 3 times more efficient. So range for a given volume of fuel storage would be about the same, or maybe a little more.
If your complaint about electric vehicles is range, I don't think hydrogen solves the problem. If it is refueling time, then maybe?
Hydrogen may be one solution to the fill-up time, grid-capacity and charging-availability problems of BEV, and so it could be a viable alternative for transport.
But it's a pig to store in useful volume and/or density, and likes to make its way through many solid materials. It's odourless and invisible when burning. Could solve those with a tiny amount of additives, but that may have other utility and environmental problems.
Personally I'd happily trade environmentally sound but less range for fill-up times and availablilty similar to current petrol/diesel. BEV are just about usable now, because hardly anyone has one. I sure don't go over the grid-capacity, charge times, charging availability, lack of off-road parking problems again that will come with mass adoption.
Solar is an odd one. It's quite good in summer. Last month it averaged 2.04GW. It is of course quite rubbish in the winter when we need power most. Las year it averaged 1.278GW.
For countries with a much more southerly latitude and especially if peak demand is in summer (air con) solar can be excellent. For the UK it is rubbish.
"or turn it into helium in fusion reactors"
Rather than using ordinary hydrogen the plans are to fuse deuterium and tritium isotopes of hydrogen as that (DT) is the most feasible. Fusion between deuterium and deuterium (DD) would be a nicer option but is much much harder. As for fusing ordinary hydrogen (HH) it's a two stage process and you need a star as the amount you can get to fuse in finite time is miniscule. This is actually a very good thing. If hydrogen hydrogen (HH) fusion worked well stars would be gone in an instant.
To me (working in energy, but not an expert) I see several positive and likely uses, with several areas I am pessimistic about.
It will probably solve a number of energy storage issues, particularly around long term storage of wind power, which is growing massively with surprisingly low costs (for those who wish to argue, the old costs were indeed high).
It solves the problem of grid capacity issues (store energy on site or wherever, just like natural gas, getting rid of the grid capacity limitations when wind is plentiful). It is early days, but quite simple to convert heavy industry (initially steel Mills) to hydrogen and the EU plans are essentially in place to do so. Pilot plants are already built and working well.
Alas, hydrogen is a very small leaky atom. It will be a fucker to use at home or in the gas grid. I'm personally not convinced home heating and transport will use huge amounts of Hydrogen power. Does need some work on cost though. In the UK, nuclear is almost dead now that offshore wind costs are less than half the final cost.
Energy demand is not a constant but varies with time of day, seasonal weather and arbitrary events. A source which copes economically with the background demand may not be able to meet peak needs, while a source which fires up at peak periods will be uneconomic as a 24/7/365 source. Some sources also vary wildly and need substantial mass storage to tide us over their quiet patches. Any viable policy adopts a mix of sources and tries to minimise the net cost to the environment and to the economy, while maintaining adequate reserve backup supplies. These aims tend to conflict, so enter the politicians and single-issue activists to screw everything up. Enjoy your career.
Exactly. Nuclear is usually pretty crap at responding to grid demand.
This is why lithium ion batteries are wonderful for grid frequency regulation. The response speed times for grid faults are currently something like:
Lithium-ion storage: 50 milliseconds
"Rapid" natural gas: 30 seconds
Hence why Li-ion embedded grid storage is popular (now they have a sensible price anyway).
You forgot, pumped storage - specifically Dinorwig - can go from zero to 1.75GW within 16 seconds or within 5 seconds if the turbines have been set spinning in compressed air first. (Interesting that Wikipedia says 75 and 16 seconds, respectively. The plant's web page just says less than 16 seconds.
There is also one big difference between the storage technologies and primary generation - stamina. Dinorwig can produce at full output - so long as the upper lake was full - for about six hours. Battery stations are typically capable of less. Gas and Nuclear (and other primary technologies) can keep going more-or-less indefinitely.
In the world of power generation, as well as in the automotive world, and even the human species, diversity is good. Putting all your eggs in one basket is inevitably a disaster in waiting, so we will continue to need backbone energy generation (nuclear fission, fusion), green generation (wind, solar, tidal, wave, etc.), and switchable generation (gas, oil, coal, hydrogen, etc). New technologies will come along and change what that mix is but the fact that it's a mix will always remain, and that's good. Nuclear is not, and probably never will be dead because we cannot rely on Wind/Solar due to something called Weather. Yes, it will hopefully someday soon switch to cleaner Fusion rather than dirty Fission but it will always be needed. As for reducing greenhouse gas emissions and similar issues, the problem remains and always will be too many people. Less people = less emissions, but we seem to be trapped in an economy where growth = more people.
The argument about cost of Wind Power against Nuclear is valid, but again, Economics 101: if the demand is high, and the supply cannot fulfil it, then the price will rise dramatically. 2.5gw actual supply in a capacity of 24gw in mid-summer is obviously not much use when the demand is 29gw, and I can still remember the freeze in 2010 when there were sub-zero temperatures for 2 two week periods when a "bubble" formed over the UK and more electricity was used to keep the windmills heated and available to work, than the windmills themselves provided. So in summer when there is no wind, or winter when there is usually too much and the windmills have to be stopped because they can't handle storms and high winds, there will be no available backup. Nuclear, suddenly becomes very cheap indeed.
Now one of the main problems is that there is still no real way to store electric power in the amounts required for society to function in case of supply flow problems IE. lack of wind. Plenty of ideas, dreams and fancies, but not here, and with so many practical problems in manufacture and design, probably for many years to come, and in a lot of cases, forever.
Hydrogen is reputed to be very clean, but on breakdown, it has major problems, the main one is it's ability to go bang when you least expect it. Hydrogen-powered vehicles will require very expensive equipment, electronics and very regular maintenance to confirm that the vehicle will not spread its contents in a spray of haemoglobin and crispy human body parts. Just imagine the fun if, in a traffic jam, one vehicle set off a chain reaction from one to the other hydrogen-powered vehicles around it. The visuals of a domino effect on the waiting 4x4 Chelsea tractors, being driven by yummy mummies waiting to drop off their precious darlings at the school gates, makes a rather dramatic perception that would send entire HV marketing departments insane.
Many thanks to previous commentators on this thread, quite a lot I was already aware of, but learning from others more knowledgeable is always a pleasure.
Have a look into the reason Hitachi started pulling out of the new UK nuclear power market.
When the latest UK wind projects are clocking in between £39 to £50 per MW hour, while the new nuclear power plants are £90 to £115 per MW hour, they could see a fundamental shift in the economics + you didn't have to worry about nuclear storage for 1000+ years.
Granted, the nuclear stations do not suffer the intermittency of wind.
Hydrogen can explode, but no more so than petrol/natural gas (I believe... could be wrong!). I believe hydrogen tends to float upwards, so in theory it has lower hazard of explosion, since any accidental release would typically result in immediate dispersion of the hydrogen upwards into the air (more complicated in confined spaces).
Said this on other threads, but here in the UK why the hell aren't we using tidal power generation?
The tides at any point on the coast are predictable to the minute for years, decades, centuries to come and tubes containing turbines on the sea bed don't destroy the view of the horizon that I lost when those bloody windfarms were built off-shore. Also no problem with being a navigation hazard to both boats and birds, or needing to cope with wind speeds beyond the structural limits of the windmill.
As for storage - the "pump water up a Welsh mountain into a lake, then let it back down through turbine generators" strikes me as both ecological and entirely feasible. Anyone calculated the footprint of all those proposed battery farms?
The problems with tidal are a) there are only a few suitable sites. yes, i know that tides happen everywhere, but you need a good fall to get useful energy, such as the River Severn. Even then the generation is not constant. Secondly it needs a large barrier which has effects on local ecology, marine navigation, coast erosion. The idea of putting turbines in the tidal flow, obviously removes some of those objections, but you need to add the engineering issues, cost of maintenance etc. Again there are only a few suitable sites.
Pump storage again is limited to a few locations.
You could also add wave power to the list, which has been looked at for many years, and never really gone with.
There are many possible solutions, but there are a lot more factors than just getting the power out
Tidal is a funny one. There is a moderate expansion of tidal going on in Scotland - SIMEC=Atlantis have a 6MW turbine array with planning permission for 400MW. https://simecatlantis.com/projects/meygen/
The historic problems with tidal were reliability, cost, site location etc. It is surprisingly difficult to get planning permission for a site to install dozens of large heavy spinning rotor blades chopping up animals/swimmers in a tidal flow area. The ocean tends to absolutely pound any machinery you put in the water and leave it requiring persistent maintenance.
the "pump water up a Welsh mountain into a lake, then let it back down through turbine generators" strikes me as both ecological and entirely feasible
It works well, but Wales doesn't have enough suitable mountains. Scotland does, if it wants to re-invent itself as England's battery :-)
A cohesive plan in this area is desperately needed. Saying "the market will deliver" will not deliver change. Money talks, so you have three options.
1) You put incentives in place for businesses to invest in X, Y and Z
2) You punitively tax the alternatives, so consumers scream for businesses to build alternatives
3) You create state-owned businesses to deliver things then sell them off (if you're a Tory).
There are organisations more than capable of delivering the scale of change but the financing HAS to be put in place or nothing will happen. David Mackay made this abundantly clear in his excellent book, Sustainable Energy Without the Hot Air.
A/C because I work in the industry and would have a vested interest in one solution being picked over another - so I won't advocate one or the other. Suffice to say the answer of having a mix of parts contributing to the solution is typically better than committing all eggs to one basket.
And one I've not heard anyone mention in public.
Every hydrogen car is a bomb.
I've read & heard proud owners (eg James May) say the gas tanks in their current models are iirc ~900 atmospheres pressure. Which is over 13,000psi, or 6 metric TONS per square inch.
Every car accident (eg as seen this week, floods banging cars around) would potentially be accompanied by one or more seriously violent explosions if the tank takes a knock, accompanied by one hell of a lot of ex-car shrapnel.
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