Does the UK need more gas power?

[Moxi]

All I was saying was new CCGT's doesn't have to mean burning natural gas or other fossil derivatives which seemed to be the position most folk were starting from. Yes there is a healthy hydrogen demand already for other uses and an awful lot of that comes from cracking natural gas, hopefully if we embrace our green energy capability as island nations we will be able to generate an excess of wind and solar and use that excess power to produce more electrolysis based hydrogen. Storage is an issue but arguably less of an issue for a static industrial unit than when considering hydrogen for aircraft, cars, consumer network etc and people are still considering those options ??

We can then use cheap (free?) power to make cheap hydrogen to make high grade fertiliser, run CCGT's make steel (its a bloody awful use of hydrogen to make steel as it causes all sorts of metallurgical problems but yes you can do it if you have no alternatives - but of course we do have alternates) or other hydrogen based industrial applications.

We need to have a joined up process using lots of wind solar and tidal/ hydro energy as the enabler to a more robust manufacturing economy producing high value goods - as part of that we clearly need some reactive generation (spinning reserve) that is suggested in this discussion as being gas turbine based and therefore could use some of the hydrogen we might otherwise use to make expensive value added goods in the short term until alternative options are established eg pumped hydro another nuke, its not necessarily long term either, we are discussing a 10 to 30 year plan.

What we cant afford is to continue entrusting the national direction and sovereign wealth potential to the whim of private investors in the desperate hope that they develop a moral approach to making a fast buck. That's never going to happen - ask Thames water staff, look at the UK power infrastructure, think about all the local corporation bus companies that disappeared and the bus service we get now or my personal favourite the railways................

We would need to start small because we are unable to bank roll large national projects anymore but it can be done if theres a will.

Moxi

[openspaceman]

NO

I tend to agree at the personal level

But what it will need is more nimble gas that does not mind being turned up and down and is profitable in the low capacity factor world. The existing gas plants are not those so we will need new plants. They will have to be cheap and probably inefficient and could even be ICE engines as are most of the present standby capacity. Infrastructure is constantly being renewed/replaced so its no big deal.

I can see the trade off in efficiency of conversion CCGT versus lower capital cost of OCGT but how about considering micro CHP using gas? CCGT may get 60+% of the heat into electricity but most houses still need heating and a simple small CHP could deliver heating and be a good fit for providing electricity in mid winter when solar PV cannot.

I know I have a parochial outlook and it doesn't fit the bulk of energy consumption in UK but simply put I generate all my own electricity for ~280 days of the year, the other 85 days I generate a good proportion except mid December to Mid January. So the period I need electricity spans 125 days (as there are 40 days in between when Solar PV provides all) but I only need 310kWh with a maximum of 12kWh (Xmas day 2023) but an average of 2.5kWh in that period. This can be done with a 3kVA generator running for an hour and a modest home battery even allowing for the losses in charge discharge. The snag is CHP units for boats are bigger and cost £10k but I only need the power of a lawnmower and running for 2 or 3 hours a day/ 300-500 hours/year. so cheap that it becomes disposable .

Even if I had an EV the fit would be good as most of the time it would charge using off peak wind/nuclear and I could run a micro CHP engine for longer and get more of my house heating from it.

BTW CCGT are ICE engines, not reciprocating though

[Saladin]

A national H₂ plant powered from what would otherwise be curtailed wind-power seems like an obvious way to make the inefficiency of electrolysis argument redundant. A national diversion load. It'd be doubly lucrative considering that energy prices go negative in low demand events.

I think we've reached the peak of chemical battery potential already. Pumped hydro is still the boss. Flow batteriers are gonna bottleneck around vanadium. There's a new spare-me!-game-changing-lynchpin-missing link-amazo-future-battery tech every month...what¿ ..sorry I tuned out as soon as I heard game-changing...

Mechanical batteries are very scalable. eg. compressed gas caverns.

The Japs have developed next generation meltdown proof nuclear reactors which make hydrogen as a by-product of the cooling process.

Only the Japs would have the ba..talent to put an Industrial H₂ storage facility beside a nuclear reactor on the Pacific ring of fire.

They are the master race.

[Ken]

I think we've reached the peak of chemical battery potential already. Pumped hydro is still the boss. Flow batteriers are gonna bottleneck around vanadium. There's a new spare-me!-game-changing-lynchpin-missing link-amazo-future-battery tech every month...what¿ ..sorry I tuned out as soon as I heard game-changing...

Not so sure about that. They may be getting close in terms of capacity/weight/£ for EVs but for storage where weight is not an issue i think there is a long way to go yet on cost perhaps with eg sodium tech. But then the costs of all batts is going to continue to decline if only because of higher volumes.

Batts can do quite a few things which pumped hydro cannot. The main one being that it can react to the rapid changes in the grid more rapid than any other and prevent safety switches tripping out. Modern inverters can also act as synchronous load and thus reduce the need to have spinning reserve.
The only common thing between batts and hydro is that they can both store but they are apples and pears.

[Ken]

It is true that in the industrial world there will be a large demand for green H2 but i do not believe this can just be run off EXCESS RE as the lack of consistency either time or place or amount is so sporidic that nobody could run a commercial operation from it and it must be debatable if a electrolyser can be run intermittently. I think it takes 30mins to get the plant up to speed ?

The production of green H2 will just become a load and be produced in countries which have vast amounts of potential for RE eg Australia.

[Krill]

A national H₂ plant powered from what would otherwise be curtailed wind-power seems like an obvious way to make the inefficiency of electrolysis argument redundant.

Since when is electrolysis of water inefficient? You are implying that there is a more energy efficient process, I'd be interested to know what that is...?

[Ken]

A national H₂ plant powered from what would otherwise be curtailed wind-power seems like an obvious way to make the inefficiency of electrolysis argument redundant.

Since when is electrolysis of water inefficient? You are implying that there is a more energy efficient process, I'd be interested to know what that is...?

In the near future this could be up to 90%+ but it really depends on what you do with the H2 produced. If the H is used immediately in an industrial process then great but if it has to stored at a cost and then somehow just burnt then it has inefficiency written all over it.

[Moxi]

But isnt switching off generating capacity more inefficient than using the power to produce something? If we dont have sufficient excess generation then I would expect any surplus power to go to industry as a kind of "power subsidy" to make UK manufacturing more economically competitive in the global market, when theirs sufficient excess generation then I would expect some of the surplus energy to go in to processes with lower returns / efficiencies. It might be the case that the international price of Hydrogen is always more than the benefit of burning it in a gas turbine (or other) generator and if that's the case then there's a decision to be made about what is used to replace the spinning reserve that would otherwise use Hydrogen gas as a fuel source.

Again the devil is in the detail and gas power needs to be considered against the type of fuel burnt, the impact on the environment, the net value obtained, the capital depreciation of the infrastructure etc etc Gas power is one of many tools in the tool box, the level we use and deploy it has many variables, and many successors and predecessors what I do think is that we cannot reply on private investment to do the right thing so this needs to be a national strategy and investment.

Moxi

[dan_b]

This is key - realistically no commercial company is going to build H2 generating infrastructure that only gets used occasionally when there is "excess" renewable power. For every hour it's not generating, it's costing money - and producing H2 only to then use it as a storage medium at some later date - rather than immediately for its chemical properties - just smacks of exergy destruction and therefore massive additional cost. There are cheaper/better ways to store energy - pump water uphill - compress air - put electricity in batteries - phase change materials.

Let's do all of those first - as we all know instinctively it's the last 10% of decarbonisation that will be the most costly, but we're not there yet.

[Countrypaul]

Converting H2 to methanol (which could be done directly with the H2 avoiding costly/dangerous storage) by using CO2 that might otherwise be put intothe atmosphere, for example, could alleviate some of the problems in storing large quantities of easily accessible energy. Storing methanol is a well established industry (similar to petrol in that it is liquid and highly inflamable), it can be easily distributed by road tanker for example and can be burnt in ICEs quite easily.

It appears that converion is about 90-95% efficient, but I can't find any information on the energy consumption for conversion.

Methanol might be safer/more acceptable than Ammonia which is also touted as a way of storing hydrogen that can be burnt in ICE.