UK energy

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roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 2 Jun 2023, 11:43am

I feel it was someone who dared to talk about and question the official narrative which prompted certain responses.

I can assure you that your feelings on this are entirely misplaced.

My own "certain response" was engendered by claims that the heat of combustion of fuel is more significant than the radiative forcing of the Co2 generated, and that Co2 cannot be an effective forcing due to it being "spread throughout the atmosphere"

These are, indeed, wholly wrong.

That a long dead celebrity botanist was cited in support was the icing on the cake.
mattheus
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Re: UK energy

Post by mattheus »

Terry Wogan didn't believe in AGW either (he mentioned it after every related news bulletin).

QED.
Biospace
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Re: UK energy

Post by Biospace »

harriedgary wrote: 1 Jun 2023, 2:22pm
So, produce lots and lots of heat energy quickly, and heh presto, the temperature will go up regardless of where that energy came from oil or solar. That only makes a longer term difference, not an immediate moment by moment difference.
This is very interesting and something few talk about. The nuclear enthusiasts won't like this argument one bit, not least since half the heat nuclear produces is wasted when producing electricity, 9% of this 50% is lost (mostly heat) in the Grid, then if you're charging an electric car, around 15% of the remaining 45% is lost in the charger and battery (mostly heat).

So around 39% remains to be used for the car's electric motor, heating and other ancilliaries, meaning 61% of the original nuclear energy is lost, mostly as heat. Which is better than approximately 30% for a diesel vehicle, including its fuel's refining and transport.

Renewables together with significantly reducing our energy consumption is surely the only long-term and fully sustainable approach.

harriedgary wrote: 1 Jun 2023, 2:22pm
The design of the UK power grid is still based on the 70s model ... which doesn't suit the latest green model of many small generation sites dotted around the countryside ... better if the money spent on large solar farms was spent giving householders and small businesses which otherwise cannot afford solar, to plant it on their many city located roofs, then the power can be used where it is made and is needed, on stuff like refrigeration and air conditioning.
Yes, place the generation where the energy is needed if possible. Motorway fast charging stations should be built where the wind blows most wherever possible (equipped with wind turbines), with mechanical flywheels or batteries storing the energy for fast release.

harriedgary wrote: 1 Jun 2023, 2:22pm
I have observed ... dwellings in greatest need of insulating... the humble pre 40s terraced house... trickier to insulate walls, and roof spaces with assorted impediments making it more expensive to insulate... they get ignored in favour of the low lying easy fruit which aren't as energy inefficient anyway.
Yup. Small minds concentrating hard on little more than money makes a mess of so many aspects of life.

harriedgary wrote: 1 Jun 2023, 3:13pm Solar panels are black(ish) so absorb more heat then they radiate... we are heading for catastrophe with the ice sheets, they reflect the sun so efficiently, replaced with brown earth that absorbs.
Covering fields with solar panels does make for more instant atmospheric warming (ask a parascender or bird of prey) relative to placing them on rooftops (as you suggest they ought to be).

As PV panels heat, they become significantly less efficient and the heat is wasted to the atmosphere, so a double-win when someone designs one which captures the heat and makes the panel more efficient in bright sunlight. It's possible that water as a coolant could be used to keep them cleaner, further improving efficiency.

Snow and ice do reflect a lot more solar radiation and this is reduced _a lot_ with soot/black carbon contamination, which is why there is a concerted push away from internal combustion engines and fires/stoves for heating.

harriedgary wrote: 1 Jun 2023, 3:13pm One or two (not many yet admittedly) environmental scientists have come out and said that while they initially supported the CO2 global warming model, they now see it differently.
It's many more than one or two, plus plenty never signed up in the first place. There's a degree of unease within significant parts of the fully-signed up to the official narrative scientific community that politicians have taken up the CO2=catastrophe scenario, not because they all believe this isn't the case, but because politics and big business increasingly controls science and funding mostly only exists if you're willing to further the political concensus on certain matters. So, they suggest, science itself suffers.

harriedgary wrote: 1 Jun 2023, 3:13pm by focusing solely on how energy is made is ignoring the elephant dying from starvation in the corner. We use too much energy, and too much resources. Cut back on that, and the world will right itself.
Do you have some data on man's production of heat vs the 'greenhouse effect'? It's a large claim to make which flies in the face of a lot of contemporary thinking.
roubaixtuesday
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Joined: 18 Aug 2015, 7:05pm

Re: UK energy

Post by roubaixtuesday »

The lifetime energy absorbed by a CO2 molecule is about 100,000 time more than the heat released in combustion if there is no corresponding increase in the earth's temperature to increase radiation.

In a 2015 paper, Ken Caldeira and a colleage (Xiaochun Zhang) showed that the cumulative radiative forcing from CO2 released in fossil fuel combustion exceeds the thermal energy released by a factor of about 100000

Blog by physics prof linked to peer reviewed paper.

https://andthentheresphysics.wordpress. ... ane-again/

If you take into account the temperature increase (which the OP claims doesn't happen), this reduces considerably.
Biospace
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Joined: 24 Jun 2019, 12:23pm

Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 2 Jun 2023, 1:17pm Blog by physics prof linked to peer reviewed paper.
Good blog and an interesting twitter discussion linked from it.

Amazing stuff, carbon dioxide - 0.04% of the atmosphere but lifetime heat capacity 100,000x more than the heat from that of combustion.

Shouldn't we be stopping its production with CO2 making machines to enhance growth of food in large glasshouses?
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 2 Jun 2023, 1:57pm
roubaixtuesday wrote: 2 Jun 2023, 1:17pm Blog by physics prof linked to peer reviewed paper.
Good blog and an interesting twitter discussion linked from it.

Amazing stuff, carbon dioxide - 0.04% of the atmosphere but lifetime heat capacity 100,000x more than the heat from that of combustion.

Shouldn't we be stopping its production with CO2 making machines to enhance growth of food in large glasshouses?
CO2 is amazing, as is physics generally!

Particularly, quantifying effects is always illuminating.

Not quite sure what point you're making re glasshouses, I vaguely recall reading somewhere that some are run with CO2 enriched atmospheres, but no idea how significant that is as an emission vs all the other emissions associated with production, or indeed if waste CO2 from heating is used. I think it's right to say that the transport emissions imported veg are less than heating emissions for glasshouse produce in the UK.
Biospace
Posts: 2006
Joined: 24 Jun 2019, 12:23pm

Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 2 Jun 2023, 2:22pm CO2 is amazing, as is physics generally!

Particularly, quantifying effects is always illuminating.

Not quite sure what point you're making re glasshouses, I vaguely recall reading somewhere that some are run with CO2 enriched atmospheres, but no idea how significant that is as an emission vs all the other emissions associated with production, or indeed if waste CO2 from heating is used. I think it's right to say that the transport emissions imported veg are less than heating emissions for glasshouse produce in the UK.
I've been told that commercial growers run engines on gas with the exhaust fed into glasshouses to increase plant growth, the waste heat (heated water) is used to warm the glasshouses and often a generator is driven to both provide lighting for plants as well as sell to the Grid.

We had a brilliant Science/Physics teacher at school who interested me for life, I remember working out how many molecules of air we inhale with each breath which someone living 2000 years ago would have inhaled at some point, assuming the atmosphere was made of the same air (which of course it isn't, but it's still an interesting thing to consider).
Jdsk
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Re: UK energy

Post by Jdsk »

Jdsk wrote: 31 May 2023, 4:36pm Some issues are strategic and can't be handled by on the merits of individual cases.

I look forward to Starmer's announcement of Labour's policy on new extraction. At the moment from what we have been told he's more right.

And the UK has major competitive advantages in many of the areas of technology and manufacturing that are needed for the transition.
Support and opposition to Starmer's position roughly as expected:
https://www.theguardian.com/politics/20 ... il-gas-ban

Jonathan
mattheus
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Re: UK energy

Post by mattheus »

Biospace wrote: 2 Jun 2023, 1:08pm <non-science mumbo-jumbo redacted - mattheus>

This is very interesting and something few talk about. The nuclear enthusiasts won't like this argument one bit, not least since half the heat nuclear produces is wasted when producing electricity, 9% of this 50% is lost (mostly heat) in the Grid, then if you're charging an electric car, around 15% of the remaining 45% is lost in the charger and battery (mostly heat).
Why is wasting nuclear energy a problem? Perhaps nuclear engineers are well aware of this! I wouldn't class myself a nuclear enthusiast, but I have a good education in the area and know the basics - wasting fission power as heat isn't a problem, as long as we get enough useful energy out (to power our bike-light chargers, and wildlife CCTV cameras; in fact if electric is cheap enough, we can heat our homes, our water, and cook our food with it too)
Biospace
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Re: UK energy

Post by Biospace »

mattheus wrote: 5 Jun 2023, 8:25am Why is wasting nuclear energy a problem?

Given the resources used to mine then mill uranium, convert the ore to uranium hexafluoride, enrich it then make the fuel - together with reactor construction, decommissioning, fuel reprocessing, nuclear waste disposal, mine site rehabilitation, and transport throughout all stages, I'd suggest that wasting half the energy from fission represents a significant carbon footprint.

I'd also argue that wasting any energy is a problem and our relaxed attitude to this reflects our fossil fuel mindset.

Over the last 100 years attitudes towards energy have changed from its conservation and careful use to one where significant wastage is the norm. Nuclear appears to be a get out of jail free card for those who wish to continue to use energy with a similar mindset seen in the second half of the C20th, often by those who are extremely concerned about a climate catastrophe.

Yet studies show that pursuit of nuclear strategies risks taking up resources that could be used more effectively and suppressing the uptake of renewable energy, which is faster to counter carbon emissions and can evolve more quickly to improve performance as well as reduce costs.

This article is well worth a read, https://socialsciences.nature.com/posts ... t-research
as is this, https://www.sciencealert.com/here-s-why ... s-possible
roubaixtuesday
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Re: UK energy

Post by roubaixtuesday »

Biospace wrote: 5 Jun 2023, 12:19pm
mattheus wrote: 5 Jun 2023, 8:25am Why is wasting nuclear energy a problem?

Given the resources used to mine then mill uranium, convert the ore to uranium hexafluoride, enrich it then make the fuel - together with reactor construction, decommissioning, fuel reprocessing, nuclear waste disposal, mine site rehabilitation, and transport throughout all stages, I'd suggest that wasting half the energy from fission represents a significant carbon footprint.

I'd also argue that wasting any energy is a problem and our relaxed attitude to this reflects our fossil fuel mindset.

Over the last 100 years attitudes towards energy have changed from its conservation and careful use to one where significant wastage is the norm. Nuclear appears to be a get out of jail free card for those who wish to continue to use energy with a similar mindset seen in the second half of the C20th, often by those who are extremely concerned about a climate catastrophe.

Yet studies show that pursuit of nuclear strategies risks taking up resources that could be used more effectively and suppressing the uptake of renewable energy, which is faster to counter carbon emissions and can evolve more quickly to improve performance as well as reduce costs.

This article is well worth a read, https://socialsciences.nature.com/posts ... t-research
as is this, https://www.sciencealert.com/here-s-why ... s-possible
I don't think quoting the thermal efficiency as "waste" is meaningful for nuclear (or indeed anything else). You could make the same case for geothermal, but even more extreme. It's just thermodynamics.

Nuclear lifetime carbon footprint is very low, the the impact from the upstream activities you quote is also there for renewables. See for example https://www.carbonbrief.org/solar-wind- ... ootprints/

"Crowding out" investment seems credible, but nuclear has significant environmental and practical advantages over many renewables (land use, intermittency for example), so that's not obviously a bad thing per se.

Personally, I think mix of low carbon energy makes a lot of sense. The future is hard to predict!
Biospace
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Joined: 24 Jun 2019, 12:23pm

Re: UK energy

Post by Biospace »

roubaixtuesday wrote: 5 Jun 2023, 1:02pm
I don't think quoting the thermal efficiency as "waste" is meaningful for nuclear (or indeed anything else). You could make the same case for geothermal, but even more extreme. It's just thermodynamics.

Nuclear lifetime carbon footprint is very low, the the impact from the upstream activities you quote is also there for renewables. See for example https://www.carbonbrief.org/solar-wind- ... ootprints/

"Crowding out" investment seems credible, but nuclear has significant environmental and practical advantages over many renewables (land use, intermittency for example), so that's not obviously a bad thing per se.

Personally, I think mix of low carbon energy makes a lot of sense. The future is hard to predict!
Yes, a mix of nuclear and renewables is most likely to see us through this century despite their conflicting demands. How energy storage evolves will be very interesting.

Excess or 'wasted' heat radiates away into space rapidly when there is little cloud cover, but whether burning fossil fuel or controlling nuclear fission, the greater the inefficiency in converting heat into electricity, the more fuel/larger power station is required. Nuclear power has a lower carbon footprint than for any fossil fuel, but likely not the figures the nuclear industry itself cites.

This article, written by a Physics ProfEmer at Imperial College sets out the reasons why the real world carbon figure for nuclear may be considerably higher than we're led to believe.

The low land use of nuclear energy is a very significant advantage and the main reason I see it continuing through this century, despite the costs and strategic liabilities.
mattheus
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Re: UK energy

Post by mattheus »

Biospace wrote: 5 Jun 2023, 2:10pm Excess or 'wasted' heat radiates away into space rapidly when there is little cloud cover,
It doesn't matter. The "extra" heat generated (compared to wind turbines and the like) is just irrelevant in catastrophic climate change terms. Cloud cover or no cloud cover. The science is there; I don't know why you and BillyGawdGads try to promote competing non-science.

(Your points about distractions from true renewables do seem convincing, to be fair! And I am not keen on everyone maintaining their energy usage simply beacuse we have some nukes coming online sometime soonish ... )
Biospace
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Re: UK energy

Post by Biospace »

mattheus wrote: 5 Jun 2023, 2:45pm
Biospace wrote: 5 Jun 2023, 2:10pm Excess or 'wasted' heat radiates away into space rapidly when there is little cloud cover,
It doesn't matter. The "extra" heat generated (compared to wind turbines and the like) is just irrelevant in catastrophic climate change terms. Cloud cover or no cloud cover. The science is there; I don't know why you and BillyGawdGads try to promote competing non-science.

(Your points about distractions from true renewables do seem convincing, to be fair! And I am not keen on everyone maintaining their energy usage simply beacuse we have some nukes coming online sometime soonish ... )
That was the point I was making, the extra heat itself is of no consequence since it radiates away. Think you may have misread, or misunderstood.

But carbon emissions are not inconsequential, they're directly related to efficiencies even when capturing the wind, sun or tides. And nuclear. Did you have a look at this? https://theecologist.org/2015/feb/05/fa ... low-carbon
mattheus
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Re: UK energy

Post by mattheus »

Biospace wrote: 5 Jun 2023, 3:01pm
mattheus wrote: 5 Jun 2023, 2:45pm
Biospace wrote: 5 Jun 2023, 2:10pm Excess or 'wasted' heat radiates away into space rapidly when there is little cloud cover,
It doesn't matter. The "extra" heat generated (compared to wind turbines and the like) is just irrelevant in catastrophic climate change terms. Cloud cover or no cloud cover. The science is there; I don't know why you and BillyGawdGads try to promote competing non-science.

(Your points about distractions from true renewables do seem convincing, to be fair! And I am not keen on everyone maintaining their energy usage simply beacuse we have some nukes coming online sometime soonish ... )
That was the point I was making, the extra heat itself is of no consequence since it radiates away. Think you may have misread, or misunderstood.
Well most of the posts that I have noticed started by hihglighting the excess heat generated, so can you blame me! Much later you start to mention carbon footprint.
Biospace wrote: 5 Jun 2023, 3:01pm
But carbon emissions are not, and they are directly related to efficiencies even when capturing the wind, sun or tides.
Are they? Surely that's only if you have inputs that use fossil fuels?[Which basically comes down to burning stuff] How about a windmill (or water mill) using local materials and locally grown flour? An extreme example, admittedly!

And if your carbon footprint is significantly below a coal/oil-based economy, you're winning anyway, so arguiing about a 50% loss in "efficiency" isn't all that important. We don't need to eliminate fossil-fuel use to maintain our current bio-sphere - we just need to cut it dramatically :)
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