Hydrogen Capable Natural Gas Turbines

[Richard D + 86]

10 hours ago, Wombat said:

Your math is not correct. 100 BTU of electrical energy should be starting point, as it is surplus electrical energy that will be used. Also, compression for storage need not take more than 50% of contained energy. Thus we get 100 x 0.8 x 0.5 x 0.6 x 0.9 = 21.6 BTU which is roughly the same as coal or gas.

Your comparison should be against other storage options. Pumped-storage hydroelectric is 70-80% efficient,as are lithium-ion batteries.

[Richard D + 86]

Looks like electrolysis is a non-starter for energy storage. How about the production of bio-chemicals? Ferment sewage sludge to acetic acid and electrolyse (Kolbe process) to give hydrogen at the cathode and a mixture of ethane and carbon dioxide at the anode. This mixture could possibly be thermally cracked to ethylene. Ethane is usually mixed with steam before thermal cracking.

[NickW + 2,714]

1 hour ago, Richard D said:

Looks like electrolysis is a non-starter for energy storage. How about the production of bio-chemicals? Ferment sewage sludge to acetic acid and electrolyse (Kolbe process) to give hydrogen at the cathode and a mixture of ethane and carbon dioxide at the anode. This mixture could possibly be thermally cracked to ethylene. Ethane is usually mixed with steam before thermal cracking.

I would tend to agree. 

If you have a supply of Hydrogen from surplus renewables best to convert it into something more easily stored - Ammonia primarily. Ethylene is also a good one but would need a supply of CO2.

One option with the H is to inject it into gas pipelines. In the UK 12-15% by volume is estimated to be safe and practical without any major modifications.  

Edited June 5, 2020 by NickW

[Richard D + 86]

One oven-ready technology using hydrogen is the production of iron carbide. This uses hydrogen and methane in a 5:2 ratio to reduce iron ore fines to iron carbide which can then be used for making steel. Would certainly seem to be of interest for north-west Australia,which has iron ore and natural gas plus abundant sunshine for making green hydrogen by electrolysis. International Iron Carbide market the process.

[Benjamin Woodman, EIT, MBA 0]

I think what most people don't realize is that industrial hydrogen is made FROM natural gas, by burning natural gas. Sure there are other less economical ways, but they struggle with corrosion issues or scalability.

[KateR 0]

I think what you don't realize is that there are ways to make H2 for less than the cost of NG and not using NG or electrolysis.

https://efiling.energy.ca.gov/Lists/DocketLog.aspx?docketnumber=17-HYD-01

above provides some interesting reading regarding California and the road map, additionally below provides some good reading around the whole subject.

https://www.climateworks.org/programs/carbon-dioxide-removal/getting-to-neutral/

Edited June 9, 2020 by KateR
new info

[Wombat + 1,028]

On 6/5/2020 at 5:10 PM, Richard D said:

Your comparison should be against other storage options. Pumped-storage hydroelectric is 70-80% efficient,as are lithium-ion batteries.

It is not just thermodynamic efficiency that counts. There is cost, geography and flexibility. Pumped hydro makes sense in some areas, not others. Tesla's "million mile battery" will revolutionize battery storage, but much of the world want to eliminate their dependence on imported oil and H2 gonna be big part of that. Once it reaches scale, no stopping it. It is just that H2 tech is about 10-15 years behind wind and solar. Many breakthroughs have been made just in the last 12 months, from production to transport to storage and even the design of fuel tanks. Maybe the USA will like to import plenty of oil for decades to come, but Europe and NE Asia will not. 

[Wombat + 1,028]

On 6/5/2020 at 5:10 PM, Richard D said:

Your comparison should be against other storage options. Pumped-storage hydroelectric is 70-80% efficient,as are lithium-ion batteries.

This is the future: https://eurekalert.org/pub_releases/2019-11/kift-hfn112619.php

[Dan Clemmensen + 1,011]

5 hours ago, Wombat said:

It is not just thermodynamic efficiency that counts. There is cost, geography and flexibility. Pumped hydro makes sense in some areas, not others. Tesla's "million mile battery" will revolutionize battery storage, but much of the world want to eliminate their dependence on imported oil and H2 gonna be big part of that. Once it reaches scale, no stopping it. It is just that H2 tech is about 10-15 years behind wind and solar. Many breakthroughs have been made just in the last 12 months, from production to transport to storage and even the design of fuel tanks. Maybe the USA will like to import plenty of oil for decades to come, but Europe and NE Asia will not. 

When analyzed at the detail level, CH4 from solar and wind makes little sense because it wastes energy by comparison to other approaches. However at the system level it is compelling. It provides enormous long-term energy storage and efficient long range transport on a massive scale with no new capital investment, and it allows for a seamless decentralized transition away from NG. Sure, pumped hydro is more efficient, but it requires massive capital investment and does not help with transport. Batteries are more efficient, but are at least two orders of magnitude more expensive for long-term storage. E==>H2 is more efficient than E==>CH4, but E==>H2==>E requires massive new infrastructure at scale. All of these alternatives create stranded assets that somebody must pay for. At the system level, E==>CH4==>E wins. Whether or not E==>?==>liquid fuel makes sense is more problematic: the market can decide.

[Wombat + 1,028]

On 6/5/2020 at 5:10 PM, Richard D said:

Your comparison should be against other storage options. Pumped-storage hydroelectric is 70-80% efficient,as are lithium-ion batteries.

All that matters is the cost. Hydro and Li-ion very expensive, at negative electricity prices, H2 becomes cheapest form of storage?

[Richard D + 86]

Calculate the cost of electrolysers and salt cavern storage. I have already noted that the price estimate for a salt cavern natural gas store on the English coast was £500 million. Very interested to see that Highview has an energy storage system using liquid air. Not cheap,but it actually works right now.

[Dan Clemmensen + 1,011]

2 hours ago, Richard D said:

Calculate the cost of electrolysers and salt cavern storage. I have already noted that the price estimate for a salt cavern natural gas store on the English coast was £500 million. Very interested to see that Highview has an energy storage system using liquid air. Not cheap,but it actually works right now.

Cost for any specific storage installation is not a useful number unless you also provide a meaningful number for the energy storage capacity. How much NG can that cavern store, in either GWh or cubic meters of NG? As I recall the Highview system can store 250 MWh. By comparison, Germany already has 200,000 GWh of NG storage in place and in operation.

Apparently, the UK currently has a total NG storage capacity of 2.5 billion cubic metres, which is a 12-day supply:

https://www.theyworkforyou.com/wrans/?id=2019-02-11.HL13575.h&p=13493

Edited June 20, 2020 by Dan Clemmensen

[Richard D + 86]

The capacity of the defunct Dorset natural gas storage scheme was to have been one billion cubic metres. For information; most UK natural gas supply comes from imports of LNG. North Sea output is now small,but useful. Our lack of storage and huge consumption is worrying.

[Dan Clemmensen + 1,011]

10 minutes ago, Richard D said:

The capacity of the defunct Dorset natural gas storage scheme was to have been one billion cubic metres. For information; most UK natural gas supply comes from imports of LNG. North Sea output is now small,but useful. Our lack of storage and huge consumption is worrying.

Yes, I just did a little more surfing. You "worry" that you only have a 12-day supply after shutting down the 3.1 bcm Rough facility. Your remaining 2.1 bcm is approximately equivalent to 25,000 GWh of energy, so it is "only" 100,000 times more energy storage than the Highview liquid air system's 250 MWh.

For another comparison, the UK can store about 12 days usage of NG. The US can store about 75 days of usage of NG, and we still have massive surplus production, some which we liquefy and sell to the UK, among others.

[Richard D + 86]

That is not a fair comparison. Natural gas storage is for winter usage. Highview Power system is for use later in same day or next morning.

[Dan Clemmensen + 1,011]

3 hours ago, Richard D said:

That is not a fair comparison. Natural gas storage is for winter usage. Highview Power system is for use later in same day or next morning.

We already have a viable solution for short-term storage: batteries. Highview is 50 MW, 250 MWh. This is less than the batteries currently being installed in California, which are 100 MW, 400 MWh, and the batteries provide instantaneous frequency stabilization. Batteries also leverage the economies of scale and technological advances from EVs, so Highview will need to work hard merely to keep up.

I'm talking about long-term storage because this thread is about H2 and H2-capable generators. Those generators are intended to operate as CCGTs and supply power when the batteries run out. Turbines of some sort will be needed on the few occasions during the year when renewables plus short-term fail to keep up with demand, e.g. on a winter morning during a long calm spell.

[Richard D + 86]

They said it couldn't be done-and they were right. For such a cold,calm spell there really is no good answer. There is a human side to this,as well. Legendary man in pub heard to say that it was the very devil to keep men motivated while they were kicking their heels for months on end while waiting for a cold snap. That man was the manager of the old coal-fired Rye House power station which was being retained for back-up in very cold weather,but was too inefficient for regular use. The weak Harold Wilson government was blackmailed into building a great number of coal-fired power stations,50 years ago,by the violent British mining union. We could have kept those stations as back-up for renewables,but the European Union would not allow the occasional pollution. They are now off our backs,but the damage has been done.

[Dan Clemmensen + 1,011]

5 hours ago, Richard D said:

They said it couldn't be done-and they were right. For such a cold,calm spell there really is no good answer. There is a human side to this,as well. Legendary man in pub heard to say that it was the very devil to keep men motivated while they were kicking their heels for months on end while waiting for a cold snap. That man was the manager of the old coal-fired Rye House power station which was being retained for back-up in very cold weather,but was too inefficient for regular use. The weak Harold Wilson government was blackmailed into building a great number of coal-fired power stations,50 years ago,by the violent British mining union. We could have kept those stations as back-up for renewables,but the European Union would not allow the occasional pollution. They are now off our backs,but the damage has been done.

A "right" answer is to use the existing gas-fired plants, burning E==>CH4 instead of NG. You just have to acknowledge the fact that they are part of the long-term storage/retrieval system and not baseload plants, and adapt the cost structure to match. You may or may not be able to retrain/remotivate the existing crews: if not, you need to hire new ones. The mentality must be as in the military: they are performing an essential task even if they almost never actually do what they train for. The economics must also change: you must pay for those plants to perform the essential function of just sitting there: pay for their MW rating and not for the MWh they produce annually.

I know nothing of the practical details, but I thought that NG plants were less labor-intensive than coal plants. I'm hoping that running at a low annual load factor will extend the useful plant life. At the very least it is easier to perform annual maintenance on a rotating basis.

Worst case: assume the plants should always run at a baseline of 10% capacity to keep them happy. Assume further that the E==>CH4==>E system is only 50% efficient. This just means that the wind and solar must be about 10% larger to generate the CH4 for them.