What cost Hydrogen ?

matelodave

Ectophile said:

Back in the days of town gas, nobody worried about embrittlement, even though that contained lots of hydrogen (as well as carbon monoxide).

Maybe there were enough tarry fumes in it to keep the pipes sealed.

I reckon in the days of town gas (which was a long time ago now) most gas pipes were made of steel but over the years a lot of it has been replaced with plastic (not sure what sort of plastic) which may be more or less affected by what is flowing through it.

One could assume that at the time the plastic was formulated for use with natural gas rather than higher concentrations of hydrogen  unless some clever far sighted person envisaged that there might have been an ongoing requirement to shove other gases down it and made sure that the material was robust enough for all eventualities.

It's just one of the many things that need to be considered when making decisions. No one is being negative but the thought processes of some of the green zealots are very narrow and don't actually take into account some of the ongoing implications.

QrizB

matelodave said:

Ectophile said:

Back in the days of town gas, nobody worried about embrittlement, even though that contained lots of hydrogen (as well as carbon monoxide).

Maybe there were enough tarry fumes in it to keep the pipes sealed.

I reckon in the days of town gas (which was a long time ago now) most gas pipes were made of steel but over the years a lot of it has been replaced with plastic (not sure what sort of plastic) which may be more or less affected by what is flowing through it.

The new plastic pipes are PE (polythene or polyethylene, which is literally the same stuff but for some reason engineers like to add the extra syllables).

There have been varios studies and the concluded that PE pipes are fine with hydrogen.

Eg: https://www.pe100plus.com/PPCA/Transport-of-hydrogen-with-polyethylene-natural-gas-pipes-p433.html

amtrakuk1975

How can people not see the Hydrogen hype is the latest big business con!

Creating electricty from Renewable electricity via the massive losses involving H2 production and management.  Surely direct battery storage with minimal loses is just common sence.

Reed_Richards

Plenty of people see that but big businesses can make a lot of noise. 

Ectophile

amtrakuk1975 said:

How can people not see the Hydrogen hype is the latest big business con!

Creating electricty from Renewable electricity via the massive losses involving H2 production and management.  Surely direct battery storage with minimal loses is just common sence.

Big batteries are extremely expensive.  There may be cheaper ones in development, e.g. sodium-ion.  But megawatt-hours worth of lithium-ion batteries is far too pricey at the moment.

Turning electricity into hydrogen isn't very efficient, but it's cheap.  Dunk a couple of electrodes into slightly acidic water, and you get lots of hydrogen and oxygen.  And you can sell the oxygen.

As we get more and more wind turbines, there are now times when the operators are being told to turn them off as they are generating too much.  Turning that "waste" electricity into hydrogen at least does something useful with it.

Hudsonbutler

I was told a while back that they are already putting 15% hydrogen in with the natural gas. Made me wonder about some of these explosions. 

Qyburn

The problem with hydrogen is that it can't just use "spare" or "renewable" energy. In order to even hit the 60-70% conversion that they hope for, the plant needs to run at a constant rate for eight or ten hours at a time. So in reality quite a lot will be produced by nuclear or fossil fuelled energy.

As for mixing into gas, electricity itself already has a greater carbon impact than gas, so using 50% more electricity to generate Hydrogen to use instead of gas makes no sense at all.

Qyburn

Ectophile said:

Turning electricity into hydrogen isn't very efficient, but it's cheap.  Dunk a couple of electrodes into slightly acidic water, and you get lots of hydrogen and oxygen.  And you can sell the oxygen.

Don't forget all the overheads. Compressing to 900 bars uses a lot of power, two separate compression stages in the plant we toured. That generates a lot of heat, meaning lots more power used in cooling. 

Oxygen is dumped to the atmosphere, we were told that capturing and purifying is not cost effective.

Regarding cost, the Hydrogen fuel that would drive a car for 500 miles costs around 50% more than Diesel if you take fuel duty out of the equation.

lohr500

I suppose my thoughts on this are not dissimilar to the thinking 70 years ago when nuclear power plants were being heralded as a way to provide free energy to everyone. 

If ( and I accept it is a big IF) we could safely generate massive amounts of electricity from nuclear and wind, then does it matter if end to end hydrogen production is not energy efficient?

I still think hydrogen powered vehicles are a better long term practical solution than battery power for most of the UK's population.

Filling up with hydrogen fuel quickly from a station when you need it must be more practical than :

The ability to get a charging cable to your vehicle if you only have on street parking.
Hauling round a heavy battery packed with materials that are costly to mine and refine.
Worries over the long term deterioration of the battery storage capacity. 

No science in any of the above. Just my gut feel!!!

Qyburn

lohr500 said:

If ( and I accept it is a big IF) we could safely generate massive amounts of electricity from nuclear and wind, then does it matter if end to end hydrogen production is not energy efficient?

That's perfectly logical, but would apply only if we could separate "spare" electricity.  At the moment for example hydrogen production is using electricity over 50% of which is generated by gas.

What we would really need is a hydrogen plant that can start and stop as and when surplus or cheap power is available, and lots of storage as well. 

For road use there used to be only one type of hydrogen powered car available, 500 mile range from 5kg of hydrogen if i remember correctly.