This is a wonderful piece of detailed work and much food for thought. I keep thinking of Scottie on the Starship Enterprise 'ye canna change the laws of physics'.... yet this is what the government's current strategy to Net Zero appears to be trying to do. We are heading for a cliff edge fast, it's going to make the oil crisis of the 1970s look like a walk in the park....
A tremendous piece if work David. This shows just what happens when seemingly sensible, technically gifted people do when they are overcome by groupthink and cult. I have spent many an hour in executive meetings where such people robustly challenge proposals to change business strategy, investment, workforce etc. You see people really excelling (mostly) - when it is their money. But every single green energy project/programme is riddled with unrealistic assumptions simply to maintain the dogma, when it is (perceived to be) someone else's money. Institutions such as the RS should be the bastion of objective scientific assessment not the (credible?) mouth piece of Government and industry policy. I have also worked extensively with econometric modellers and the RS work has the whiff of them. Usually nice, bright people in my experience but extremely limited in understanding the practicalities of deliverability and have the knack of making the impossible look possible on a spreadsheet. They would have little idea of the Labour demands for example - in fact David you can add a further 4000 FTE tradesmen to your 1000 technical engineers for every new billion pumped into the infrastructure sector. Like most people I talk to they assume some sort of magic to make it just so.
The RS report appears to be riddled with completely unrealistic assumptions (always the enemy of infrastructure business cases in my experience) which you have brilliantly highlighted. It would be great if you could garner a response from them.
A quote ‘Consider that 24m homes with an average 12kW heat pump operating at a COP of 2.5 on a cold mid-winter night would generate a peak demand of 115GW’
Mid OfFGEM TDCV for gas is 12000kWh across 8760 hours that’s 1.37kW. Clearly heating demand is very seasonal, but they are often modulating down to a fraction of their rating and not running flat out except in extreme circumstances.
Boiler sizes for space heating with stored water rather than instantaneous hot water demand from Worcester Bosch UK (Greenstar i system boilers) show the following sizes, 9.2,12.2,15.3,18.4,21.6 & 24.6kWh, clearly shown to reflect the sizes required for UK, from the smallest towards medium sized properties (as declared in their technical/marketing literature) I’d expect that to mean single bed flat to a three bed house.
So I’d suggest 12kW heat pumps, even in retrofits would not be the norm for the UK now, let alone 20-30 years hence. For instance Vaillant have heat pumps (ARO therm plus) in 3.5, 5, 7, 10 & 12kWh. Oversizing lowers the COP, but with the conservative COP of 2.5 you quoted the output tracks those boiler sizes and at the top end exceeds the system boiler sizing by 22%.
Anecdotal evidence of retrofit installations recently in the UK points to 5kW being a quite common size.
I would suggest that retrofits will preferentially be in properties that are better suited to them. That will mean modern (and therefore small) properties with good insulation. No-one is going to be in a great hurry to install heat pumps in Victorian terraces or even 1930s or 1950s semis.
It's better to argue from gas consumption data and the savings on that that might be anticipated. A look at the age of the housing stock also helps.
Actual UK transmission gas demand at and around the peak might provide some degree of guidance on actual peak heat requirements
I still maintain a 12kW heatpump is massively oversized for an average UK property regardless of age. It’s the same mentality that sticks an oversized boiler because everyone does it. A 30kW boiler in a 3 bed semi is often ridiculously oversized for space heating , it might be ok if it’s a combi to meet hot water demand AND it can modulate to prevent short cycling as that really helps with efficiency. That’s why I used a system boiler in my post above as it more closely matches the space heating / stored water a heat pump system provides.
Retrofits of heat pumps in older leaky properties appear to be reasonably common.
Peak gas demand during the beast from the east was 214GW. Add on oil-fired properties snd existing electricity heated properties, then divide by 2.5 and you won't be far from my fag packet estimate. In fact 2.5 when it's <-5C outside might be generous.
I have been researching hydrogen cavern storage, including Linde, Texas, Teesside and the project at Stublach where a direct comparison can be made in the same strata. They all seem to have much lower operating pressures than methane storage. To some degree, cavern pressure is related to depth, and designed to offset the pressure from the weight of overburden. But the lower pressures for hydrogen suggest a lack of confidence that higher pressures might risk cavern integrity. The consequence of only being able to operate at up to 120-150 bar is that you will need rather more cavern space. Given that hydrogen is less than a third of the energy density of methane at the same temperature and pressure we are perhaps looking at 5 times as much storage space per TWh. There is also the need for cushion gas, which is the gas that remains at the minimum cavern pressure at the lower end of the working range. The working range depends on the minimum acceptable pressure for cushion gas to avoid too much stress on the cavern roof. Cushion gas must be injected before storage operations can start, and might eventually be recovered at the end of cavern life when they would have to be refilled with brine to avoid or at least reduce risk of subsidence.
Your comparison with Algeria, Mexico, Brazil and Paraguay ignores the fact that they are rather warmer countries than the UK, with relatively little need for heating (and also limited aircon use). If we correct for that the result is a much lower standard of living than those countries.
That's a good dive into the innards of the RS report. On the one hand it remains largely based on the fantasy studies used by the CCC for its carbon budget reports, and on the National Grid Future Energy Scenarios that you have previously delved into, and relied on by DESNZ in designing policy. On the other, it does for the first time begin to question one of the key assumptions underpinning all that, which is that Dunkelflaute periods are always short lived and followed by energy glut, so the need for storage and backup is very limited. That has been a feature of similar work all around the world that I have seen. From now on, all future plans are going to have to acknowledge that reality, so as more of the fantasy assumptions unwind in the face of reality we reach a point where the whole edifice implodes. This is an important lever because of the gearing effects of storage on the whole system.
It leads to overbuild to try to economise on costly storage and its appendages. Indeed, they are assuming overbuild not merely to cover the round trip losses through storage, but also for curtailment. Any time storage is full surpluses must be curtailed. They may also be curtailed due to capacity limitations on how rapidly storage can be filled - even when stores still have ullage. Hence why we have 741TWh vs 570TWh - 171TWh of round trip losses and curtailment. They do not draw attention to this aspect, even in the detailed supplementary papers, but it is there. There is only a limited mention of production being 1.3-1.8 times demand. They do not consider higher ratios because their assumptions give them cheap supply ex storage.
You are correct in your conclusion and yes the report should be assigned trash status. The hydrogen issue is simply a further distraction as that cost like the battery costs are assigned to taxpayers instead of being taken into the risk calculation.
Unfortunately the RE industry has not covered themselves in any glory as far as the belief system shows.
As Francis Menton said in his crit of the same article that there was never a successful demo project for Re and we most probably won't see one for Hydrogen either. He says "If anybody thought that the demonstration project I proposed could be built at reasonable cost to make a profit, then multiple entrepreneurs would already be building these things. Meanwhile the costs are buried so no one can figure them out. We have a desperate need for a real demonstration project. UK, you are the one to do it!
I remember the blocking anti-cyclone of 2010 which becalmed the entire country for about a month. That didn’t matter much to the electricity supply as at that time our dependency on weather-dependent wind power was low.
It was also bitterly cold midwinter when power is needed most and the roads were all salted. I had to journey from Nairn to Glasgow by car but my windscreen skoosher was frozen solid and I had to stop every few miles to clean the windscreen of road salt manually.
It seems to be fashionable in scientific papers these days for conclusions to conform to the narrative while raising serious questions in the main body of the report. Political reality will dictate that the UK’s gas infrastructure will never be dismantled.
Nice summary of the many failings in the RS report.
One thing I did not see here, was the extra generation capacity needed to power the hydrogen backup system. In an ideal world with a 100% efficient backup (or a 90% efficient backup like pumped water), the excess energy on windy days will go to the storage system. Meaning that no extra installed wind capacity will be needed, to power the hydrogen ‘battery’.
However, if the battery is losing 60% of its energy, then extra wind capacity will be needed to top up those battery inefficiencies. (Your data suggests the hydrogen battery is even less efficient than this.) Assuming we will need to completely recharge the battery over one month we may need 50 gw of actual energy (125 gw of installed) just to top up the battery.
In addition, I don’t like the RS’s 570 twh annual energy calculation. Not only is theirs too low, but it is largely irrelevant. What we need to know is peak demand over the three or four months of winter. A more realistic annual consumption may be 1,200 twh, but 600 twh of that may be required in the four months of winter. Extra generating capacity will be needed to meet that high winter demand.
I would be interested on your thoughts as to how much installed capacity will be needed, bearing in mind the potential 600 twh of energy required in the four months of winter, and the possibly 70% inefficiencies of the battery system.
I'm coming to the same conclusion.... just do it, do it quickly, get it over with and then let's move on, but only after we've had the cultists on trial. Not sure how that last bit will work but I feel strongly that every political leader (and their inner anctum) since Blair should be made accountable for this gargantuan waste of money and loss of opportunity.
This is a wonderful piece of detailed work and much food for thought. I keep thinking of Scottie on the Starship Enterprise 'ye canna change the laws of physics'.... yet this is what the government's current strategy to Net Zero appears to be trying to do. We are heading for a cliff edge fast, it's going to make the oil crisis of the 1970s look like a walk in the park....
A tremendous piece if work David. This shows just what happens when seemingly sensible, technically gifted people do when they are overcome by groupthink and cult. I have spent many an hour in executive meetings where such people robustly challenge proposals to change business strategy, investment, workforce etc. You see people really excelling (mostly) - when it is their money. But every single green energy project/programme is riddled with unrealistic assumptions simply to maintain the dogma, when it is (perceived to be) someone else's money. Institutions such as the RS should be the bastion of objective scientific assessment not the (credible?) mouth piece of Government and industry policy. I have also worked extensively with econometric modellers and the RS work has the whiff of them. Usually nice, bright people in my experience but extremely limited in understanding the practicalities of deliverability and have the knack of making the impossible look possible on a spreadsheet. They would have little idea of the Labour demands for example - in fact David you can add a further 4000 FTE tradesmen to your 1000 technical engineers for every new billion pumped into the infrastructure sector. Like most people I talk to they assume some sort of magic to make it just so.
The RS report appears to be riddled with completely unrealistic assumptions (always the enemy of infrastructure business cases in my experience) which you have brilliantly highlighted. It would be great if you could garner a response from them.
A quote ‘Consider that 24m homes with an average 12kW heat pump operating at a COP of 2.5 on a cold mid-winter night would generate a peak demand of 115GW’
Mid OfFGEM TDCV for gas is 12000kWh across 8760 hours that’s 1.37kW. Clearly heating demand is very seasonal, but they are often modulating down to a fraction of their rating and not running flat out except in extreme circumstances.
Boiler sizes for space heating with stored water rather than instantaneous hot water demand from Worcester Bosch UK (Greenstar i system boilers) show the following sizes, 9.2,12.2,15.3,18.4,21.6 & 24.6kWh, clearly shown to reflect the sizes required for UK, from the smallest towards medium sized properties (as declared in their technical/marketing literature) I’d expect that to mean single bed flat to a three bed house.
So I’d suggest 12kW heat pumps, even in retrofits would not be the norm for the UK now, let alone 20-30 years hence. For instance Vaillant have heat pumps (ARO therm plus) in 3.5, 5, 7, 10 & 12kWh. Oversizing lowers the COP, but with the conservative COP of 2.5 you quoted the output tracks those boiler sizes and at the top end exceeds the system boiler sizing by 22%.
Anecdotal evidence of retrofit installations recently in the UK points to 5kW being a quite common size.
I would suggest that retrofits will preferentially be in properties that are better suited to them. That will mean modern (and therefore small) properties with good insulation. No-one is going to be in a great hurry to install heat pumps in Victorian terraces or even 1930s or 1950s semis.
It's better to argue from gas consumption data and the savings on that that might be anticipated. A look at the age of the housing stock also helps.
https://www.statista.com/statistics/292252/age-of-housing-dwellings-in-england-uk-by-tenuree/
I think OFGEM have a spreadsheet somewhere breaking the TDCV analysis down into property size, I can’t find it at the moment.
Regardless the OFGEM TDCV mid range closely tracks the median & mean gas consumption across the whole of GB
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1126186/subnational_gas_consumption_statistics_2005-2021.ods
Median consumption 11,344.9kWh
Mean consumption 12,959.8kWh
Actual UK transmission gas demand at and around the peak might provide some degree of guidance on actual peak heat requirements
I still maintain a 12kW heatpump is massively oversized for an average UK property regardless of age. It’s the same mentality that sticks an oversized boiler because everyone does it. A 30kW boiler in a 3 bed semi is often ridiculously oversized for space heating , it might be ok if it’s a combi to meet hot water demand AND it can modulate to prevent short cycling as that really helps with efficiency. That’s why I used a system boiler in my post above as it more closely matches the space heating / stored water a heat pump system provides.
Retrofits of heat pumps in older leaky properties appear to be reasonably common.
Peak gas demand during the beast from the east was 214GW. Add on oil-fired properties snd existing electricity heated properties, then divide by 2.5 and you won't be far from my fag packet estimate. In fact 2.5 when it's <-5C outside might be generous.
https://ukerc.ac.uk/news/gas-consumption-during-beast-from-the-east/#:~:text=The%20Beast%20from%20the%20East,on%20the%201st%20of%20March.
I have been researching hydrogen cavern storage, including Linde, Texas, Teesside and the project at Stublach where a direct comparison can be made in the same strata. They all seem to have much lower operating pressures than methane storage. To some degree, cavern pressure is related to depth, and designed to offset the pressure from the weight of overburden. But the lower pressures for hydrogen suggest a lack of confidence that higher pressures might risk cavern integrity. The consequence of only being able to operate at up to 120-150 bar is that you will need rather more cavern space. Given that hydrogen is less than a third of the energy density of methane at the same temperature and pressure we are perhaps looking at 5 times as much storage space per TWh. There is also the need for cushion gas, which is the gas that remains at the minimum cavern pressure at the lower end of the working range. The working range depends on the minimum acceptable pressure for cushion gas to avoid too much stress on the cavern roof. Cushion gas must be injected before storage operations can start, and might eventually be recovered at the end of cavern life when they would have to be refilled with brine to avoid or at least reduce risk of subsidence.
It's worse than we thought, Jim!
Your comparison with Algeria, Mexico, Brazil and Paraguay ignores the fact that they are rather warmer countries than the UK, with relatively little need for heating (and also limited aircon use). If we correct for that the result is a much lower standard of living than those countries.
That's a good dive into the innards of the RS report. On the one hand it remains largely based on the fantasy studies used by the CCC for its carbon budget reports, and on the National Grid Future Energy Scenarios that you have previously delved into, and relied on by DESNZ in designing policy. On the other, it does for the first time begin to question one of the key assumptions underpinning all that, which is that Dunkelflaute periods are always short lived and followed by energy glut, so the need for storage and backup is very limited. That has been a feature of similar work all around the world that I have seen. From now on, all future plans are going to have to acknowledge that reality, so as more of the fantasy assumptions unwind in the face of reality we reach a point where the whole edifice implodes. This is an important lever because of the gearing effects of storage on the whole system.
It leads to overbuild to try to economise on costly storage and its appendages. Indeed, they are assuming overbuild not merely to cover the round trip losses through storage, but also for curtailment. Any time storage is full surpluses must be curtailed. They may also be curtailed due to capacity limitations on how rapidly storage can be filled - even when stores still have ullage. Hence why we have 741TWh vs 570TWh - 171TWh of round trip losses and curtailment. They do not draw attention to this aspect, even in the detailed supplementary papers, but it is there. There is only a limited mention of production being 1.3-1.8 times demand. They do not consider higher ratios because their assumptions give them cheap supply ex storage.
You are correct in your conclusion and yes the report should be assigned trash status. The hydrogen issue is simply a further distraction as that cost like the battery costs are assigned to taxpayers instead of being taken into the risk calculation.
Unfortunately the RE industry has not covered themselves in any glory as far as the belief system shows.
As Francis Menton said in his crit of the same article that there was never a successful demo project for Re and we most probably won't see one for Hydrogen either. He says "If anybody thought that the demonstration project I proposed could be built at reasonable cost to make a profit, then multiple entrepreneurs would already be building these things. Meanwhile the costs are buried so no one can figure them out. We have a desperate need for a real demonstration project. UK, you are the one to do it!
I remember the blocking anti-cyclone of 2010 which becalmed the entire country for about a month. That didn’t matter much to the electricity supply as at that time our dependency on weather-dependent wind power was low.
It was also bitterly cold midwinter when power is needed most and the roads were all salted. I had to journey from Nairn to Glasgow by car but my windscreen skoosher was frozen solid and I had to stop every few miles to clean the windscreen of road salt manually.
Interesting that you quote Carl Sagan who was somewhat of an early proponent of AGW.
https://youtu.be/Wp-WiNXH6hI?si=jRIytrFiHWg1bFZl
It seems to be fashionable in scientific papers these days for conclusions to conform to the narrative while raising serious questions in the main body of the report. Political reality will dictate that the UK’s gas infrastructure will never be dismantled.
Nice summary of the many failings in the RS report.
One thing I did not see here, was the extra generation capacity needed to power the hydrogen backup system. In an ideal world with a 100% efficient backup (or a 90% efficient backup like pumped water), the excess energy on windy days will go to the storage system. Meaning that no extra installed wind capacity will be needed, to power the hydrogen ‘battery’.
However, if the battery is losing 60% of its energy, then extra wind capacity will be needed to top up those battery inefficiencies. (Your data suggests the hydrogen battery is even less efficient than this.) Assuming we will need to completely recharge the battery over one month we may need 50 gw of actual energy (125 gw of installed) just to top up the battery.
In addition, I don’t like the RS’s 570 twh annual energy calculation. Not only is theirs too low, but it is largely irrelevant. What we need to know is peak demand over the three or four months of winter. A more realistic annual consumption may be 1,200 twh, but 600 twh of that may be required in the four months of winter. Extra generating capacity will be needed to meet that high winter demand.
I would be interested on your thoughts as to how much installed capacity will be needed, bearing in mind the potential 600 twh of energy required in the four months of winter, and the possibly 70% inefficiencies of the battery system.
Ralph
I'm coming to the same conclusion.... just do it, do it quickly, get it over with and then let's move on, but only after we've had the cultists on trial. Not sure how that last bit will work but I feel strongly that every political leader (and their inner anctum) since Blair should be made accountable for this gargantuan waste of money and loss of opportunity.
🎯🎯🎯