Hydrogen home heating

[not done it yetParticipant @notdoneityet]

A good explanation, Nigel. Platinum and (more recently) Palladium catalysts are used to convert oxides of nitrogen and carbon monoxide emissions from petrol engine combustion to people-safe molecules. Ad-Blue is primarily used for removing the particulates from diesel engine combustion exhaust streams (although even petrol engines produce some particulates, they are ignored by most – as they are small, compared to those from diesel engines).

An ICE has advantages of a wide range of output power (roughly proportional to engine speed) whereas fuel cells generally operate at constant output (meaning that for a variable power use, some form of energy storage is required when the power required exceeds the fuel cell output)

Petrol fuelled IC engines are typically only about 25% efficient (hydrogen fuelled may be a little more) and diesels around 30%. Some very large diesel engines can be as good as 50% efficient (think multi MW marine drives).

A typical car alternator is around 50% efficient. That means that electricity for your car systems may only use 12% of the heated inputted from the fuel. Most large alternators are better than 85% efficient. Coal fired power stations typically operate at ~40% efficiency.

Electricity is regarded as a high grade energy source – it can be used effectively while being transformed into heat (100%), motive power (50-95% for conveyor belts, compressors, hydraulic pumps, driving cars, etc), chemical energy (electrolysing water for instance @70%, charging batteries @50-90+%) and a host of other uses in manufacturing and science.

The upshot of the above means that producing hydrogen by electrolysis @`70% efficiency is only viable when there is spare electrical power available at very low cost (we cannot store ‘electricity&rsquo. With renewable energy, the alternatives to transforming the excess electrical energy, to a ‘lower grade’ of energy, is to waste it (lots of wind energy generation is turned off at times for that very reason). Hydrogen production is just one option of the former.

The Danes are currently building a huge wind farm which will do just that – make electricity for immediate grid distribution or use any excess to produce hydrogen. They are streets ahead of the UK in this respect – but they do have a good resource and don’t waste as much the UK does.

This thread is a much more complex issue than envisaged by most. Local injection of high pressure stored-hydrogen might be one angle on reducing system leakages, but don’t let a load of mis-truths spoil a good news article on the beeb.

Burning hydrogen cleanly is not the same as producing it cleanly.

[Steve Skelton 1Participant @steveskelton1]

NDIY, Nigel is right regarding Ad-Blue. It is injected into the exhaust after the diesel particulate filter and reacts in the selective catalytic reduction system in the exhaust system to give a final outcome of nitrogen, carbon dioxide, and water. It is not designed to have any particulate reducing action. Ad-Blue is very pure urea in a de-ionized water mixture.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Neil Lickfold on 19/05/2021 11:37:25:

When I hear about Hydrogen gas supplies, I think of the Hindenburg .

.

Here’s an interesting update on that: **LINK**

https://www.smithsonianmag.com/smart-news/unearthed-footage-sheds-new-light-hindenburg-disaster-180977773/

MichaelG.

[Nigel Graham 2Participant @nigelgraham2]

Why does mentioning "hydrogen" as a fuel lead some people to think "Hindenburg"? Not relevant!

As a digression though…

I did follow that link. I have seen the more complete newsreel than that usually shown, starting a moment before the fire first appears. It shows the airship approaching the mooring-mast but pitching more and more severely, with the crew trying to control it by discharging a lot of water from the bow tanks, for an appreciable time before the fire.

As it happens I listened to Mark Steel In Town this morning, an episode recorded in Bedford in 2017. He mentioned the modern airship that has been built locally, the largest in the world now; and as evidently many of the audience had done too, he saw it fly over the town earlier that day.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Nigel Graham 2 on 26/05/2021 20:49:52:

Why does mentioning "hydrogen" as a fuel lead some people to think "Hindenburg"? Not relevant!

[…]

.

But Neil didn’t actually reference ‘hydrogen as a fuel’ … he referenced ‘Hydrogen gas supplies’

… somewhat more relevant

MichaelG.

[Nigel Graham 2Participant @nigelgraham2]

OK, gas supplies… but it's still fuel. It was the 'Hydrogen' cue I picked up on.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Nigel Graham 2 on 27/05/2021 12:58:56:

OK, gas supplies… but it's still fuel. It was the 'Hydrogen' cue I picked up on.

.

I had assumed [the discussion having digressed to vehicular applications] that you were reminding us that the Hindenburg’s motive power source was not Hydrogen.

[although there were design proposals for a fifth engine, adapted to run on ‘surplus’ Hydrogen]

**LINK**

Hindenburg Design and Technology

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

News :

**LINK**

https://qz.com/2020924/volvo-is-planning-to-make-cars-with-low-carbon-steel/

MichaelG.

[John HaineParticipant @johnhaine32865]

In other news, Aston-Martin is planning to use high-speed steel…

[Neil AParticipant @neila]

That had me puzzled for a while, why would you change to low carbon steel to make a car? Then I realised it was only the process for making the steel that was going to be low carbon, not the steel its self.

Just shows how news reports can be written to make things sound totally different to the reality of the news. I don't suppose the writer knew that "low-carbon steel" was a particular group of steel specifications.

As Mark Twain once commented: "Facts are tricky things, best left to the experts".

Neil

Edited By Neil A on 16/06/2021 12:20:43

[duncan webster 1Participant @duncanwebster1]

A bit off track, but perhaps a route to hydrogen cars grey goo. Just depends on the energy input/output balance and whether the magnesium oxide can be recovered

[J HancockParticipant @jhancock95746]

Forget it , I wrote to my MP (again ) about the censored news of Dungeness B closing seven years early, etc.

After some delay, the reply , they will do another 'dash for gas', constructing quick build CCGT stations to make up for lost 'nukes' .

That's all they can do now , in the time available..

[duncan webster 1Participant @duncanwebster1]

Not very well censored! BBC

It actually closed 10 years after it's sign life, originally planned to close 2008. But yes I agree with JH, governments of all hues have been sadly lacking in forethought about generating capacity. I'm a big supporter of wind and solar, but when it's dark and the wind isn't blowing we need something to keep the lights on. The present shower won't even let us dig up our own coal to make steel or run heritage railways. There is not as yet a proven industrial scale non coal way of making steel, by all means invest in development, but it isn't going to happen tomorrow, we'll just import it with a bigger carbon footprint

[J HancockParticipant @jhancock95746]

I accept you are correct to say it is not 'totally' censored BUT you only see that headline when the last word is typed in….Kent,

Same as it only appeared in the Kent messenger local paper , as a headline.

Generally, as hushed-up as possible.

[Nigel Graham 2Participant @nigelgraham2]

To think the UK used to be among the world's leaders in developing nuclear power-generation, though I think it did suffer a big blow when France stopped funding a partnership in this.

I listened to an edition of Any Questions some weeks ago now when the matter of coal-mining came up, and it was clear that none of the panel had a clue why coal is still necessary in making "steel" (iron, actually). I recall learning it in school geography lessons – and at quite a young age, too.

The alternative reducing agent being investigated is hydrogen, but what of course its proponents seem to gloss over are the sources of the gas, and the method of heating the ore to the appropriate temperature.

[duncan webster 1Participant @duncanwebster1]

So here's another, Times 08 June Times

I wrote to my MP, he didn't seem to care about steel making, and couldn't comprehend that steam locos need special coal

[J HancockParticipant @jhancock95746]

Me too, about the Cumbria noncoal-mine , the Chinese 'bought' our last steel asset in Scunthorpe on the promise of locally sourced coal from Cumbria !

[Ady1Participant @ady1]

We've currently got a carbon capture project high on the politicos agenda

1 Give 100s of millions of free money to new company

2 claim you're saving the planet

3 consume vast amounts of energy to run the plant 24/7 at 1000 degrees celcius

4 claim you're saving the planet

5 retire somewhere nice with a big bag of public cash in your piggy bank

[SillyOldDufferModerator @sillyoldduffer]

Posted by duncan webster on 29/06/2021 21:46:25:

…

I wrote to my MP, he didn't seem to care about steel making…

And nor should we! At least not in the sense that large scale steel production in the UK is an option.

Steel making consumes gigantic quantities of coking coal, limestone, water, oxygen, iron ore and scrap. As the consumables are all expensive to transport, it's best to manufacture steel close to the raw materials and with excellent transport faculties, ideally a sea-port. And because steel works take up a lot of space, about 7 square kilometres, land had better be cheap!

The UK was once exceptionally well-favoured with water, coal, limestone, iron-ore and sea-ports. Not so today; most of the UK's coal and iron-ore have been extracted and consumed. What's left of our coal is roughly enough to meet world demand for a year, and it's deep underground. I'm sure it will be extracted in due course, but there's reason to wait for the best price. That Whitehaven coal has become economic to extract again is a sign demand is outstripping supply. The cost of coal is rising because god isn't making any more.

Impossible to predict what the world will be like in 2120. One thing is certain, energy and products made from fossil fuels won't be cheap. Everything has it's day, and humanity moves on. Nothing to do with tree-hugging, the need to find alternatives to fossil fuels is urgent.

Dave

[not done it yetParticipant @notdoneityet]

That project says there is already a plant doing just that in Canada. Removes a ton of CO2 per day, apparently.

Gas fired electricity generation is currently running at 14GW, producing a tonne and a half of CO2 every second.

I also believe that project is, as Ady 1 points out, basically just a scam to make money for themselves from the public purse.

Seems someone doesn’t really understand the meaning of ‘large’ and ‘significant’ in this context.

[duncan webster 1Participant @duncanwebster1]

Whilst I can see the argument against making iron in this country when we have to import the iron ore, we've got the plant to do it, we've got limestone, and we've got coal if the government would let us dig it up. If we can keep jobs in this country why not do it. Even if we stop exporting scrap steel and use it to re-make our own, if there is a market elsewhere for coking coal why turn it away? If we don't dig it up someone else will. Shifting your carbon footprint offshore doesn't make it go away.

The other big non power use of coal is making cement. I'd better shut up or the government will close that down as well

[Ady1Participant @ady1]

Posted by duncan webster on 30/06/2021 11:51:33:

The other big non power use of coal is making cement. I'd better shut up or the government will close that down as well

Ah but they won't… because its themselves and their buddies who are the beneficiaries

HS2, Sizewell B and any other project which milks the system needs concrete

One of the most ridiculous wastes of energy is un-necessary air travel, which is even subsidised with dirt cheap fuel. The fuel is so cheap planes just dump the stuff as part of their flight procedures

[not done it yetParticipant @notdoneityet]

The other big non power use of coal is making cement. I'd better shut up or the government will close that down as well

Cement manufacture likely only uses 10-12% Standard Coal (for fuel, these days, I would think (all dry process and large preheater kilns, along with burning alternative fuels eg scrap tyres chlorinated solvent waste, etc) so each tonne of cement likely produces half a tonne of CO2 from the fuel.

The other main additional CO2 emissions in the manufacture is derived from the raw materials; these lose approximately a third of their weight as CO2 (from the chalk or limestone in the raw feed) which now doubles the amount of CO2 emitted to the atmosphere.

Most certainly a significant CO2 polluting industry but an ideal candidate for carbon capture, I might suggest.

The above does not, of course, address the electricity consumption of the quarrying, clinker manufacture or grinding processes.

I gather HS2 has caused a shortage of cement in the building industry recently – I wonder how much pollution that particular project is responsible for.🙂

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