This is another brilliant article, Chris. An exposé using easy to follow analysis of the utter futility of pursuing the 100% renewables path to 'net zero'/eliminating fossil fuel usage. It is, almost literally, "tilting at windmills".
I will have to re-read several times to get comfortable with some of the maths and science but I have already linked to this article on other social media I follow.
Amazing that the 'no nonsense', pragmatic analysis falls on someone like you, doing this non-professionally, when it should really be taken up by officially sponsored and supported engineering/science researchers in industry or academia.
Massive respect for your commitment to truth and integrity. Thank you.
It discusses the recent spate of negative wholesale electricity prices in Europe caused by surplus solar generation and the prospect for a lot more surplus, and how it varies between countries. There is discussion of the need to curtail subsidies for surplus production, but no realisation that this means there would need to be higher prices for useful output to compensate. Also a rather bland assumption that variable demand (when you charge your EV) plus green hydrogen will solve it without looking at what that would take. The $64bn question you rightly ask. There is also an arrogant assumption that nuclear should give way to solar with no justification. They are still way behind the curve in their thinking.
You're right that hydrogen is not a viable way forward. Incidentally, I think the stability limit you identify is a bit higher than you suggest. It should include nuclear output that can't readily be turned off just because it's windy, and arguably even some of the import capacity that provides a steady input to the grid, although it doesn't offer inertia (and indeed interconnector trips are now the biggest source of larger frequency deviations, increasingly offset by batteries). As the nuclear shuts down we may need to run more gas to maintain adequate grid stability. National Grid has two approaches to this: one is taking bigger risks by lowering stability standards and hoping that battery response is fast and big enough when things start to go wrong, and the other is investing in additional stabilisation kit such as synchronous compensators. If it does go wrong the August 2019 blackout is likely to be vastly exceeded.
Back to hydrogen. I find it useful to look at renewables surpluses as duration curves. This highlights the fact that the interaction of varying demand and varying generation produces varying surpluses. It is never going to be economic to attempt to handle the largest surpluses, because you would have to build grid and electrolyser capacity to service them that would only be called upon very rarely. So you are still going to wind up with a large chunk of curtailment anyway. This chart gives a flavour of the duration curves you could expect from different levels of wind capacity (I made it when we had about 22GW installed, so the curves are for multiples of this up to 132GW).
It's a mouseover chart. If you select a point on one of the curves you get a readout of the grid and electrolyser capacity you need to install, and the utilisation it would get: everything to the left and above your point gets curtailed. Note that there remains a big proportion of the time when there is no surplus - especially if you only have limited wind capacity installed. If you use hydrogen to power generators when there is a deficit you will suffer the whammys of a very low round trip efficiency (say 60% for a PEM electorlyser, perhaps somewhat less in intermittent mode, and 50% for an intermittent gas generator, so no better than 30% overall) as well as higher costs from low utilisation of the generator.
Of course in practice these surpluses are going to vary significantly on very short timescales - as demand picks up ahead of the morning rush hour for example, or when a weather system moves through, or as the sun goes higher in the sky in summer. As you point out that's not good for efficient operational performance of electrolysers.
Clearly what you should not do is to try to keep the utilisation of the electrolysers higher by running them even when you have no surplus: you would be burning inefficiently made hydrogen to make hydrogen at a very low efficiency. The CCC idea of using floating offshore wind to run electorlysers is completely nuts. It takes the most expensive form of wind generation as the input to the process, and multiplies the cost due to the inefficiencies. It also (because there is no other choice) will end up with hydrogen being made instead of using directly produced electricity - exactly the scenario to avoid.
I have downloaded the demand, wind and solar data from gridwatch for 2022 into an Excel file to model UK Labour’s proposal to decarbonise the electricity by 2030 by quadrupling offshore wind, doubling onshore wind and trebling solar.
I calculate that for this 2030 proposal where the average power demand is 36 GW and maximum 56GW we will require :
Hydrogen storage : 19 TWhrs = 600K tonnes (taking a generating efficiency of 40%)
Battery : 10 TWhrs
I have also made some costings, but these were before the offshore wind industry, requesting a “budget” increase, failed to make any bids for AR5.
If anyone else is interested in seeing and checking my method & calculations please email me at jbxcagwnz@gmail.com
"Of course, until GB and other countries honestly account for embedded emissions in imports, we will continue to de-industrialise to the benefit of other countries. But that’s a complete whole other story apparently too complex for our ‘leaders’ to grasp, so they’ll continue to pursue policies that reduce CO2-only in-territory emissions that incentivise our economic decline."
Economic decline is the purpose of Net Zero not an unintended consequence.
This is another brilliant article, Chris. An exposé using easy to follow analysis of the utter futility of pursuing the 100% renewables path to 'net zero'/eliminating fossil fuel usage. It is, almost literally, "tilting at windmills".
I will have to re-read several times to get comfortable with some of the maths and science but I have already linked to this article on other social media I follow.
Amazing that the 'no nonsense', pragmatic analysis falls on someone like you, doing this non-professionally, when it should really be taken up by officially sponsored and supported engineering/science researchers in industry or academia.
Massive respect for your commitment to truth and integrity. Thank you.
I found this podcast was quite interesting.
https://www.buzzsprout.com/257968?client_source=large_player&iframe=true&referrer=https://www.buzzsprout.com/257968.js?container_id=buzzsprout-large-player&player=large#
It discusses the recent spate of negative wholesale electricity prices in Europe caused by surplus solar generation and the prospect for a lot more surplus, and how it varies between countries. There is discussion of the need to curtail subsidies for surplus production, but no realisation that this means there would need to be higher prices for useful output to compensate. Also a rather bland assumption that variable demand (when you charge your EV) plus green hydrogen will solve it without looking at what that would take. The $64bn question you rightly ask. There is also an arrogant assumption that nuclear should give way to solar with no justification. They are still way behind the curve in their thinking.
You're right that hydrogen is not a viable way forward. Incidentally, I think the stability limit you identify is a bit higher than you suggest. It should include nuclear output that can't readily be turned off just because it's windy, and arguably even some of the import capacity that provides a steady input to the grid, although it doesn't offer inertia (and indeed interconnector trips are now the biggest source of larger frequency deviations, increasingly offset by batteries). As the nuclear shuts down we may need to run more gas to maintain adequate grid stability. National Grid has two approaches to this: one is taking bigger risks by lowering stability standards and hoping that battery response is fast and big enough when things start to go wrong, and the other is investing in additional stabilisation kit such as synchronous compensators. If it does go wrong the August 2019 blackout is likely to be vastly exceeded.
Back to hydrogen. I find it useful to look at renewables surpluses as duration curves. This highlights the fact that the interaction of varying demand and varying generation produces varying surpluses. It is never going to be economic to attempt to handle the largest surpluses, because you would have to build grid and electrolyser capacity to service them that would only be called upon very rarely. So you are still going to wind up with a large chunk of curtailment anyway. This chart gives a flavour of the duration curves you could expect from different levels of wind capacity (I made it when we had about 22GW installed, so the curves are for multiples of this up to 132GW).
https://datawrapper.dwcdn.net/nZM72/1/
It's a mouseover chart. If you select a point on one of the curves you get a readout of the grid and electrolyser capacity you need to install, and the utilisation it would get: everything to the left and above your point gets curtailed. Note that there remains a big proportion of the time when there is no surplus - especially if you only have limited wind capacity installed. If you use hydrogen to power generators when there is a deficit you will suffer the whammys of a very low round trip efficiency (say 60% for a PEM electorlyser, perhaps somewhat less in intermittent mode, and 50% for an intermittent gas generator, so no better than 30% overall) as well as higher costs from low utilisation of the generator.
Of course in practice these surpluses are going to vary significantly on very short timescales - as demand picks up ahead of the morning rush hour for example, or when a weather system moves through, or as the sun goes higher in the sky in summer. As you point out that's not good for efficient operational performance of electrolysers.
Clearly what you should not do is to try to keep the utilisation of the electrolysers higher by running them even when you have no surplus: you would be burning inefficiently made hydrogen to make hydrogen at a very low efficiency. The CCC idea of using floating offshore wind to run electorlysers is completely nuts. It takes the most expensive form of wind generation as the input to the process, and multiplies the cost due to the inefficiencies. It also (because there is no other choice) will end up with hydrogen being made instead of using directly produced electricity - exactly the scenario to avoid.
In case of interest:
I have downloaded the demand, wind and solar data from gridwatch for 2022 into an Excel file to model UK Labour’s proposal to decarbonise the electricity by 2030 by quadrupling offshore wind, doubling onshore wind and trebling solar.
I calculate that for this 2030 proposal where the average power demand is 36 GW and maximum 56GW we will require :
Hydrogen storage : 19 TWhrs = 600K tonnes (taking a generating efficiency of 40%)
Battery : 10 TWhrs
I have also made some costings, but these were before the offshore wind industry, requesting a “budget” increase, failed to make any bids for AR5.
If anyone else is interested in seeing and checking my method & calculations please email me at jbxcagwnz@gmail.com
"Of course, until GB and other countries honestly account for embedded emissions in imports, we will continue to de-industrialise to the benefit of other countries. But that’s a complete whole other story apparently too complex for our ‘leaders’ to grasp, so they’ll continue to pursue policies that reduce CO2-only in-territory emissions that incentivise our economic decline."
Economic decline is the purpose of Net Zero not an unintended consequence.