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Hydrogen, No Thanks !


hilldweller
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As someone who worked with Hydrogen gas on an industrial scale and saw in practice just how explosive the stuff is and just how difficult it is to safely contain I wonder if the boffins who think it is the fuel of the future have any practical experiance of the stuff.

The Stocksbridge Works Light Products used huge quantities of the stuff as an atmosphere gas during the annealing of high quailty stainless steel strip and wire. It was delivered in large trailers with either about ten very big steel cylinders along the length of the trailer (4+3+2+1) or in smaller cylinders in frames across the width.  These trailers would be discharged into static banks and piped in copper pipes around the factory.

The stuff has a very wide explosive  limit of combustion, approx 4% to 75 % and the flame speed is phenominal. Under certain conditions it can even detonate in a similar way to high explosives.

It will seek out the smallest leak to escape, It's molecular size is so small. We used it as an "inert" gas within sealed retorts that the steel was pulled through. It is inert in the sense that the steel which was at about 1050 degrees celsius does not tarnish.

In the smaller wire furnaces the wire was pulled through steel tubing with a tee junction in the middle for the H2 feed. The ends were stuffed with ceramic fibre to limit the gas flow. When the fuel tech lads had measured the H2 content the ends were carefully lit, often with a loud bang.

The carcase of the furnace was flooded with nitrogen at an higher pressure than the H2 to keep the stuff in the retorts as the gas would otherwise escape through the hot steel as if it wasn't there.

I was working one day on an electrical panel about 30 feet away when I was hit in the back by a piece of ceramic fibre about the same size and mass as a cotton wool ball. It propelled me into the panel (thankfully not live) and caused a bruise about 6 inches wide. It would have a mass of a few grams.

What had happened was that the stuffing had fallen out of the other end of the pipe, air had got in and the very rapid flames spread down the tube had compressed the remaining gas to detonate and eject the other plug of fibre from the other end.

Do I want an hydrogen fuelled house, no fear. Natural Gas explosions can demolish a house, Hydrogen explosions would deposit it in the next town.

If they are going to produce the H2 by electrolysis from electricity, why not use the electricity to heat the houses. Technology exists now to store vast amounts of power when the sun is not shing or the wind blowing.

Just a thought.

hilldweller.

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Hydrogen only makes sense when a location is off the electricity grid, so I agree with your last point.  I'd be interested to see a proper safety comparison between petrol, LPG and hydrogen though.  The great virtue of hydrogen is that it will ascend if it leaks, whereas the other two spread across the flooring.  To take two examples: boating and vehicles.  I will not have either LPG or petrol aboard my boat.  In the case of leaks the fuel sinks to the bilges, spreads along the hull and can then erupt in a sheet of flame from which there is no escape.  In the case of a car accident the petrol (and its invisible vapour) spreads across the road surface, under the crashed vehicles.  Imaging being trapped in a car with petrol flowing under you.

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Regarding the ability of Hydrogen to safely dissipate skywards, it can't always be relied upon to keep going upwards.

During the last few years of my duties as Process Control Engineer a large extension was built to the Cold Rolled Strip Department.

This was to accomodate a very large Austrian made annealing/hardening furnace to produce the 14" wide strip for a well known Sheffield cutlery firm to produce a range of knives.

The retort was a spun steel tube the best part of a metre in diameter and many metres long. The retort was electrically heated within a steel carcase which was pressurised with nitrogen. At the outgoing end was a big box structure containing a high pressure Hydrogen compressor which was aranged to squirt cool Hydrogen out of knife like nozzles onto the top & bottom surface of the steel to harden it. Hydrogen of course is a very good conductor of heat.

To try to keep the Hydrogen in, the strip entered and left the retort through sprung high temperature rubber rollers but of course some escaped at the ends. No attempt was made to flare the escaping gas but it was allowed to escape up into the roof.  The building roof was provided with many louves which made up at least 50% of the roof area.

Despite this and the flameproof light fittings, the gas would sometimes ignite with a loud woomth up above the people below.  You couldn't see it burning but the explosion would blow all the dust off which would fall through the burning gas and produce little glowing orange spots as it decended.

Why it built up like that instead of continuing skywards I don't know but perhaps it was due to weather conditions, a layer of damp air stopping the Hydrogen escaping.

The amount of protective gear to keep the thing safe was huge. The control panel was about 20 feet long and 12 feet deep. We used to joke about holding the Christmas Dinner Dance in there instead of at Cubley Hall.

It's all gone now, replaced by a shopping centre and the residents of Stocksbridge can sleep soundly now. It's replacement will be somewhere in China I should think. They are welcome to it.

hilldweller

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Despite this and the flameproof light fittings, the gas would sometimes ignite with a loud woomth up above the people below.  You couldn't see it burning but the explosion would blow all the dust off which would fall through the burning gas and produce little glowing orange spots as it decended.

That though is the point, it was above the people below, if that had been petrol ...

I suspect (and may be completely wrong) that your experience with MASSIVE amounts of compressed hydrogen in an industrial setting isn't exactly paralleled by the expected use of hydrogen as a transport fuel.  Pushing steel through rubber rollers is not something that is done in either fuel cells or internal combustion engines.  There have been problems with valves and transmission lines, but as I understand things they are under control now (again, I may be proved wrong).  The studies I've seen suggest that hydrogen as a car fuel is less likely, battery technology is improving all the time, but for HGVs and marine applications effective stored electricity is a long way off.  Short of banning long distance HGV transport (electric railways anyone?), the currently viable alternatives are diesel or hydrogen.

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Interesting.I vividly remember ,aged 11 ,experimenting with the stuff in the chemi -lab at Grammar school……we all enjoyed the “pop “as it exploded in the test tube…..measuring the H2O produced was the challenge!

One of my grandsons is about to finish his apprenticeship with a multinational engineering group….who, according to my grandson, are well on the way to taming the gas for use in domestic boilers!

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Any more info on that Lysanderix?  I assume this will be for people who are "off grid" and currently use LPG or oil, though with the government's plan to ban the connection of new builds to the gas grid it could become more widespread.

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Domestic boiler manufacturers are all ready producing hydrogen ready boilers, these have the ability to burn both natural gas and hydrogen gas.  Keel University is testing the effects of using a blend of 80% natural gas and 20% hydrogen, apparently most gas appliances in use today will work with this so called blend.

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I see that Toyota has launched a hydrogen fuel cell car.  It's being released as infrastructure becomes available.  Refuelling in 2-5 minutes and a range comparable with petrol cars.

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Listening to a discussion with various experts on the radio this morning, I don't think this will affect many of us in our lifetime.

Like 96% of Sheffield households, we use Gas for heating because it is on demand and cheap.  We could use electricity for the same purpose at the flick of a switch but choose not to.

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I suspect that "in our lifetime" is highly variable.  I'm unlikely to see 2030 but I'd hope there are those here who are hoping to see 2100.  That's quite a bit of time and change.

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Hydrogen is being pushed by gas suppliers as a 'zero-carbon' alternative to keep their infrastructure going. The problem is that it takes more than twice as much electricity to make 'green' hydrogen via electrolysis as it would if the electricity was used directly in the home. And more than six times if that electricity powers a domestic heat pump.

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No energy conversion (including transformers and also long supply cables) can ever be 100% efficient so cutting out a conversion will always tend to improve efficiency.  However, when there is no feasible way of supplying the electricity, hydrogen becomes a serious contender.  Domestic mains gas is probably a case where long-term it doesn't make sense, though in the short term it allows the considerable existing capital (both financial and energy) to be utilised.  However for transport purposes supplying electricity is difficult.  Batteries are also inefficient and use some fairly rare ingredients.  Overhead or surface pick-ups are fine for rail or canal, but are not really practical with road transport or shipping.  Hydrogen however is stable and energy dense.  Hydrogen is also a good standby where today portable gas heaters and generators are needed, such as remote locations and camping.

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There's just been an item on ITV's News at 10 about hydrogen.  One extra point that they covered is the use of a gas for cooking, something considered essential by professional chefs.  Having had to change from gas to electric domestically I can understand their reluctance!

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