Posted by: @derek-m

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hydrogen produces water vapour not CO2

Unlikely to be straight hydrogen without new technology turbines, so likely to be fuel mix for the foreseeable future.

Hydrogen is zero CO2 emissions, not zero emissions, so for example it still produces NOx when used as a fuel source, but way worse than methane gas, approx 6x that of methane gas. NOx is not good either.

So would expect that flue gas would be hoovered away also.

Posted by: @johnmo

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Posted by: @derek-m

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hydrogen produces water vapour not CO2

Unlikely to be straight hydrogen without new technology turbines, so likely to be fuel mix for the foreseeable future.

Hydrogen is zero CO2 emissions, not zero emissions, so for example it still produces NOx when used as a fuel source, but way worse than methane gas, approx 6x that of methane gas. NOx is not good either.

So would expect that flue gas would be hoovered away also.

I do believe that Siemens are developing modification for their gas turbines so that they can burn pure Hydrogen.

To ensure we keep the physics in mind:

'Natural gas' has a Calorific Value of around 39 MJ/cubic-m, with a statutory minimum of 37.
The CV of Hydrogen is 12 MJ/cubic-m.

Thus you need over three times more hydrogen than natural gas to produce the same heat output,
and it takes 3x the energy to pump it along a pipe network.

If/when hydrogen is to be produced as a fuel in Britain, it will be piped separately rather than put into the existing gas pipelines. It's most likely to be done in areas that already have excess electricity generation from renewable sources. Those are

• Scotland (mainly hydro, but increasingly wind-turbines)
• SW England (mainly solar, but increasingly wind, both of which will soon be arriving from Morocco as well)
• North Sea coast (offshore wind-farms)

Scotland and SW England already produce more electricity that ESO can accept across the national grid.
It either gets discarded, or ESO 'pays off' the generation sites which have offered the electricity.

That leaves the North Sea connections from offshore wind-farms as the best location for hydrogen production.
Check the Transition Grid map to see where those connections are close to an existing CCGT site, and those are the obvious generation sites for a trial.

That map portion is from Appendix-A of the ESO Electricity Ten Year Statement (ETYS).

Posted by: @derek-m

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Posted by: @johnmo

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Posted by: @derek-m

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hydrogen produces water vapour not CO2

Unlikely to be straight hydrogen without new technology turbines, so likely to be fuel mix for the foreseeable future.

Hydrogen is zero CO2 emissions, not zero emissions, so for example it still produces NOx when used as a fuel source, but way worse than methane gas, approx 6x that of methane gas. NOx is not good either.

So would expect that flue gas would be hoovered away also.

I do believe that Siemens are developing modification for their gas turbines so that they can burn pure Hydrogen.

 

All turbine manufacturers are, developing hydrogen fuel systems. But there is zero infrastructure to get huge volumes required to site.  Plus the whole methane gas process upstream of the turbine needs to be replaced, with bigger and different gas conditioning required. Quite a few metallurgy issues to resolve with high pressure hydrogen and long term reliability. So quite some time off for a wholesale rollout.

They are also looking at running on HVO, altogether very simple as nothing different equipment wise than straight diesel is needed. Lots of supposed green credentials, but in reality overhyped, still the same tail pipe emissions, but credit being taken for CO2 as the oil would have otherwise gone to waste. So again need flue gas processing and storage.

Posted by: @lucia

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I wish they'd stop with the hydrogen and carbon capture nonsense.... 

'They' are no longer Ministers and civil servants creating policies in Whitehall.

'They' are the Directors and senior management of the National Energy System Operator (NESO),

... and they have names, faces and job roles which are available for us to view on ESO's website.

They're predominately from an engineering background and quite willing to describe what they actually do.
For example here's a very informative YouTube interview with Claire Dykta, who describes how ESO 'balance' supply and demand.

The future path towards Net Zero has been wrested from Government and placed in the hands of the Independent System Operator and Planner, which I've just explained on another topic here.

So if we have views/insights into what this Executive Team is doing, then we can email them and say so.
In a democracy, there will be times when we should be doing so.

On the technicalities of Nodal Pricing, hydrogen-generation and carbon capture, I no longer have to first write to my MP who then forwards my letter to the Secretary of State for a response.

What's interesting about NESO is that they could decide on technical grounds not to spend vast sums of money on a particular energy strategy.
I wonder how that will be viewed by Ministers who tend to announce big grand schemes with uncertain viability.

Posted by: @johnmo

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Why is it nonsense?

Stripping power station emissions at the flue stack and processing, then pumping into spent oil and gas fields out of harms way. 

Renewable energy is great, if the sun's out or it's windy, if it's neither fire up the combined cycle gas generator, process the flue gas. Better still while it's windy make hydrogen with the excess spinning reserve then feed the gas turbines with it.

"It takes more energy to produce, store and transport hydrogen than it provides when converted into useful energy, so using anything but new renewable sources (true green hydrogen) will require burning more fossil fuels."

And even so-called 'green hydrogen' is a diversion. 

There are possibly a few niche industrial uses but for day-to-day home energy use it is just a tactic by Big Fossil Inc to delay decarbonisation. 

@johnmo

I didn't say it was a simple solution, but I feel it is probably better than paying wind farm operators not to generate.

In Winter the vast majority of renewable generation will be from wind, and say that the peak demand is 40GW, but there is very little wind and all the wind farms can only produce 10% of their maximum rated capacity. It would therefore be necessary to have 400GW of wind farm capacity to meet demand. The next day is quite windy, with the wind farms producing 80% of their rated capacity, so production is now 320GW, but peak demand is still 40GW, so production is 8 times demand.

While this is a simple example, it nevertheless highlights the problem of not having some form of bulk storage of energy.

By having energy storage in appropriate locations (a further problem to resolve) there would be a requirement for much less renewable capacity, with the excess production being stored when there is a surplus, and being used to fill the gaps when there is a deficit.

Obviously it does require careful long term planning to create such a system.

I'm not holding my breath.

Posted by: @lucia

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It takes more energy to produce, store and transport hydrogen than it provides when converted into useful energy,

But it would be made with spare renewable energy from Wind, that cannot be absorbed by the grid. So as not waste it. On windy day there can be many wind turbines turned off because there is no market for the electric, the producers get paid producing or not

I think we're agreed on that point @johnmo 

Hydrogen produced from surplus renewable-generation is therefore a good example of a Locational Storage asset.

... and that's another reason why development of the technology is linked to GB adopting Nodal pricing.

@johnmo Read the article I linked to....

But there's numerous others. 

@transparent

At last, it would appear that we now have some 'grown-up' involved in the decision making, rather than merely the occupants of the Westminster kindergarten.

@transparent

While it was quite an interesting video, one thing that did concern me was the number of times the word 'market' was used for what after-all should be a National Strategic Asset.