UK energy

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roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

I don't think efficiency is very helpful as a metric in this context, as the definition is very different for say wind, solar and nuclear.

All could be made to look good or bad depending on what you call "efficiency".

Carbon footprint allows more of a direct comparison on a like for like basis.

Even there, though, if the need for storage and impact of intermittency and the carbon footprint of despatchable backup is considered, it's impossible to be definitive about the absolute carbon footprint.

Thanks for the link to the emeritus Prof analysis. Interesting, but not definitive would be my view.
Biospace
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Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 5 Jun 2023, 3:43pm I don't think efficiency is very helpful as a metric in this context, as the definition is very different for say wind, solar and nuclear.

All could be made to look good or bad depending on what you call "efficiency".

Carbon footprint allows more of a direct comparison on a like for like basis.

Even there, though, if the need for storage and impact of intermittency and the carbon footprint of despatchable backup is considered, it's impossible to be definitive about the absolute carbon footprint.

Thanks for the link to the emeritus Prof analysis. Interesting, but not definitive would be my view.
I'm somewhere between his figures and the government's. Certainly the new(ish) EPR has caused enormous problems at Flamanville and their older French fleet is proving very expensive to maintain.

The efficiency of PV and wind turbines becomes more relevant if their energy is used to manufacture new PV and turbines, supplying industry (including with e-hydrogen storage) and domestic demand. Renewables are increasing in efficiency, storage is the key.

There's little scaled compatibility with nuclear and renewables in either economic or technical terms but increasingly large Grids and significantly more storage should improve overall generation efficiencies. This century is likely to see a broad base of technologies to transition us into the post fossil fuel era, perhaps something as unusual as whether or not the Ukrainian Zaporizhzhia plant survives intact without nuclear catastrophe will have more effect on medium term sources of energy than more scientific and economic analysis.

mattheus wrote: 5 Jun 2023, 3:11pm How about a windmill (or water mill) using local materials and locally grown flour? An extreme example, admittedly!
I almost mentioned a traditional watermill or windmill, serving its locality with gear and shaft driven grinding wheels. The levels of overall efficiency for this setup - including transportation - are high, it would be very interesting to see the figures side by side with those for today's 'high efficiency' flour production methods, from field to plate.

While we have gained an enormous amount of knowledge through the oil age we've also cast plenty aside, some of which could yet be recycled for our own benefit. The idea of a circular economy is good, but could be problematic with modern materials and PCBs. According to https://www.lowtechmagazine.com/2018/11 ... onomy.html our consumption of resources has more than doubled that of population growth through the C20th.
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 5 Jun 2023, 5:49pm
roubaixtuesday wrote: 5 Jun 2023, 3:43pm I don't think efficiency is very helpful as a metric in this context, as the definition is very different for say wind, solar and nuclear.

All could be made to look good or bad depending on what you call "efficiency".

Carbon footprint allows more of a direct comparison on a like for like basis.

Even there, though, if the need for storage and impact of intermittency and the carbon footprint of despatchable backup is considered, it's impossible to be definitive about the absolute carbon footprint.

Thanks for the link to the emeritus Prof analysis. Interesting, but not definitive would be my view.

I'm somewhere between his figures and the government's. Certainly the new(ish) EPR has caused enormous problems at Flamanville and their older French fleet is proving very expensive to maintain.

The efficiency of PV and wind turbines becomes more relevant if their energy is used to manufacture new PV and turbines, supplying industry (including with e-hydrogen storage) and domestic demand. Renewables are increasing in efficiency, storage is the key.

There's little scaled compatibility with nuclear and renewables in economic or technical terms but increasingly large Grids and significantly more storage should improve overall generation efficiencies. This century is likely to see a broad base of technologies to transition us into the post fossil fuel era, perhaps something as unusual as whether or not the Ukrainian Zaporizhzhia plant survives intact without nuclear catastrophe will have more effect on medium term sources of energy than more scientific and economic analysis.

mattheus wrote: 5 Jun 2023, 3:11pm How about a windmill (or water mill) using local materials and locally grown flour? An extreme example, admittedly!
I almost mentioned a traditional watermill or windmill, serving its locality with gear and shaft driven grinding wheels. The levels of overall efficiency for this setup - including transportation - are high, it would be very interesting to see the figures side by side with those for today's 'high efficiency' flour production methods, from field to plate.

While we have gained an enormous amount of knowledge through the oil age we've also cast plenty aside, some of which could yet be recycled for our own benefit. The idea of a circular economy is good, but could be problematic with modern materials and PCBs. According to https://www.lowtechmagazine.com/2018/11 ... onomy.html our consumption of resources has more than doubled that of population growth through the C20th.
I don't understand what you mean by "efficiency" here and I *think* you're using it in different ways in different contexts.

I suggest to have a meaningful conversation it would be useful for you to define the term in each context.

I would be very surprised indeed if a waterwheel driven stone grinding mill were as efficient as modern hydro and electrical modern milling machinery for flour production, measured against kgs flour per unit of gravitational potential energy, including all distribution. But that's mere hunch with no data.
Biospace
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Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 5 Jun 2023, 5:58pm
I don't understand what you mean by "efficiency" here and I *think* you're using it in different ways in different contexts.

I suggest to have a meaningful conversation it would be useful for you to define the term in each context.

I would be very surprised indeed if a waterwheel driven stone grinding mill were as efficient as modern hydro and electrical modern milling machinery for flour production, measured against kgs flour per unit of gravitational potential energy, including all distribution. But that's mere hunch with no data.
Quite so. As a definition of useful energy out compared with energy input when talking about efficiencies of PV panels increasing.

When mentioning the 'overall generation efficiencies' of electricity Grids with respect to interconnection and their effective increase in size, it's in the broader way - in that a smaller overall generation capacity can exist with interconnected Grids, particularly so with higher proportions of renewable energy.

"Overall levels of efficiency... including transport" of the journey of grain from field to table in the C19th compared with today was intended to consider and compare the carbon footprint for a unit of harvested grain to be transported to a flour mill, processed, packed and transported to retailer then kitchen table. Very slack/incorrect use of the word, my apols.

It's fairly obvious, to me at least, that modern flour mills will use less energy than ancient ones to produce a unit of flour, but that could be construed as misleading given the (at present) reliance on fossil fuel to build a modern mill, make the machinery, to power it and in transportation throughout, and of the materials.

The process of making most bread today is often talked about as being 'efficient' since it takes very little time, but the energy inputs are higher, per loaf, than with the traditional method. These are Wikipedia's words: The Chorleywood bread process (CBP) is a method of efficient dough production to make yeasted bread quickly, producing a soft, fluffy loaf. Compared to traditional bread-making processes, CBP uses more yeast, added fats, chemicals, and high-speed mixing to allow the dough to be made with lower-protein wheat, and produces bread in a shorter time.
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 5 Jun 2023, 7:05pm
The process of making most bread today is often talked about as being 'efficient' since it takes very little time, but the energy inputs are higher, per loaf, than with the traditional method. These are Wikipedia's words: The Chorleywood bread process (CBP) is a method of efficient dough production to make yeasted bread quickly, producing a soft, fluffy loaf. Compared to traditional bread-making processes, CBP uses more yeast, added fats, chemicals, and high-speed mixing to allow the dough to be made with lower-protein wheat, and produces bread in a shorter time.
I don't think the quote tells you anything about energy inputs. I would expect from grain to plate including milling, dough manufacture, and baking the total energy input per kg bread made is considerably less than historically, with baking being the dominant input, and modern mass throughout ovens far more efficient than traditional ones.

But again, this is based on hunch rather than data, so is not a reliable guide.
Jdsk
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Re: UK energy

Post by Jdsk »

roubaixtuesday wrote: 5 Jun 2023, 3:43pm I don't think efficiency is very helpful as a metric in this context, as the definition is very different for say wind, solar and nuclear.

All could be made to look good or bad depending on what you call "efficiency".

Carbon footprint allows more of a direct comparison on a like for like basis.
...
Yes, it's important to be really clear about benefits and harms in any decision analysis. Emission of carbon dioxide is a harm.

Jonathan
Biospace
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Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 5 Jun 2023, 7:34pm I don't think the quote tells you anything about energy inputs. I would expect from grain to plate including milling, dough manufacture, and baking the total energy input per kg bread made is considerably less than historically, with baking being the dominant input, and modern mass throughout ovens far more efficient than traditional ones.

But again, this is based on hunch rather than data, so is not a reliable guide.
The quote was used at the end of a reply to your point about the use and intended meaning of "efficiency", to demonstrate both the everyday use of the word in very slack terms and to indicate it's sometimes used as a replacement word for 'greater profit', often ignoring negative externalities.

The industrialisation of bread production with the Chorleywood process involves between 5x and 8x more energy than traditional methods. https://bakerpedia.com/processes/chorle ... g-process/

Larger ovens should be more efficient (lower surface area to volume ratio), I would expect large flour mills reduce energy waste over small ones. However, as Jdsk points out, it's the carbon footprint and global warming potential which matters. We should also be aware of eutrophication and generation of human toxins.

Jdsk wrote: 6 Jun 2023, 10:20am
roubaixtuesday wrote: 5 Jun 2023, 3:43pm Carbon footprint allows more of a direct comparison on a like for like basis.
Yes, it's important to be really clear about benefits and harms in any decision analysis. Emission of carbon dioxide is a harm.
So to use this in respect to how the conversation has moved to discussion of grain to table 'efficiency', it has been calculated that 589g CO2 is embodied in every (800g) loaf of bread if the crop growing is included - the CO2 output from 5km by diesel car.

Synthetic fertilser - 43%
Baking - 9.7%
Milling/cleaning 9.1%
Drying, storage, transport - 8.7%
Agricultural machinery - 5.2%
Packaging - 3.1%

https://bakeryinfo.co.uk/finished-goods ... 21.article

My hunch is the lifecycle carbon emissions from field to plate for a loaf of bread when agriculture and industry would be termed 'inefficient' by most today (horses providing farm power and transport, windmills and watermills for grinding grain) would've been lower, despite inefficient production of horseshoes and iron used in agriculture and mills, or the fires burning to make lime for spreading on the land.
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 6 Jun 2023, 5:53pm

The industrialisation of bread production with the Chorleywood process involves between 5x and 8x more energy than traditional methods. https://bakerpedia.com/processes/chorle ... g-process/
Sorry but that's completely misleading.

It refers only to the kneading part of the process, and is likely a trivial part of the entire baking process.
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 6 Jun 2023, 5:53pm

So to use this in respect to how the conversation has moved to discussion of grain to table 'efficiency', it has been calculated that 589g CO2 is embodied in every (800g) loaf of bread if the crop growing is included - the CO2 output from 5km by diesel car.

Synthetic fertilser - 43%
Baking - 9.7%
Milling/cleaning 9.1%
Drying, storage, transport - 8.7%
Agricultural machinery - 5.2%
Packaging - 3.1%

Interesting breakdown, thank you
Biospace
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Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 6 Jun 2023, 6:31pm
Biospace wrote: 6 Jun 2023, 5:53pm The industrialisation of bread production with the Chorleywood process involves between 5x and 8x more energy than traditional methods. https://bakerpedia.com/processes/chorle ... g-process/
Sorry but that's completely misleading.

It refers only to the kneading part of the process, and is likely a trivial part of the entire baking process.

Using the same links already provided, kneading would appear to use 1.2% of the total, therefore maybe 1% extra overall. With 11 million loaves sold every day, that is significant - around 65000 kg CO2 per day.

However, we should remember that additional additives to the flour are required to make the CBP work, which appear to represent up to around 5% of the carbon emissions of bread - like the artificial fertilizer, a disproportionately large amount.

Agricultural practices represent 66% of the embodied carbon in bread at present but there is huge scope for reducing this considerably. Transport will becomes less FF-dependent, electricity for the mills is steadily reducing its embodied carbon and gas bread ovens will eventually be changed for electric ones leading to the process itself starts to look disproportionately energy intensive.

If it somehow made better tasting more nutritious bread, then fine. I've never been to another European country where the overall quality of the nation's bread has been so low - it's a result of the post-war years with limited food but ever cheaper energy. Little wonder British consumption of bread is falling.

https://www.theguardian.com/commentisfr ... mment.food
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 6 Jun 2023, 7:56pm

If it somehow made better tasting more nutritious bread, then fine. I've never been to another European country where the overall quality of the nation's bread has been so low - it's a result of the post-war years with limited food but ever cheaper energy. Little wonder British consumption of bread is falling.

https://www.theguardian.com/commentisfr ... mment.food
I've not in any way defended let alone advocated the Chorleywood bread process. I would sooner eat my own liver with a teaspoon* than consume a slice of that textureless excuse for a foodstuff. A couple of slices of excellent toasted sourdough with home made marmalade for me this morning!

But excessive energy use has nothing to do with its adoption, as far as any facts presented here can guide us.

*Ok, maybe a teensy exaggeration.
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simonineaston
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Re: UK energy

Post by simonineaston »

It's not often I type any words in support of the ghastly industrialised food industry, but it does occur to me wonder if the Chorelywood process may have made a lot of sense back when it was developed, when a major challenge was just producing enough food to get everyone fed.
I'm not in anyway attempting a comparison between the nutrional content of fermented and Chorelywood loaves or the subjective eating experience, but rather just pointing out that back when it was developed and adopted, it resulted in a huge increase in the volume of bread produced as well as a decrease in the cost of production. Other perceived pluses might have been the uniformity of the resulting product and the potential to more readily add ingredients like preservatives and fortifying chemicals.
And lastly, it must be put on record that the only proper way to create a good old British bacon sarnie is by using the stuff !!
S
(on the look out for Armageddon, on board a Brompton nano & ever-changing Moultons)
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

simonineaston wrote: 6 Jun 2023, 9:04pm
And lastly, it must be put on record that the only proper way to create a good old British bacon sarnie is by using the stuff !!
Reported to mods.

The *only* acceptable use for Chorleywood bread is the Breville cheese toastie.

The bacon sarnie is authentic solely when constructed with a barm cake.
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

A traditional Breville cheese toastie, incidentally, is the only known example of a system disobeying the first law of thermodynamics; the heat of the inside being proven to exceed that input to it from the outside.
Jules59
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Re: UK energy

Post by Jules59 »

And Pop Tarts can be used to create the heat of the sun in your own kitchen
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