Broken out a little better in the supplemental index. They don't seem to explain the x-axis value well - what is this range of $9-12/capita? Regardless if such a 1/3 increase in income is associated with such a drastic increase in energy use and CO2 emissions, that is unfortunately impressive.
:
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Climate Change / Global Warming Discussion
- Thread starter Raffy.Roma
- Start date
-
- Tags
- Energy Environment Policy
SageBrush
REJECT Fascism
So 'affluent' is just click bait. All the more reason to be surprised by the relatively small difference between the groups
mspohr
Well-Known Member
SageBrush
REJECT Fascism
Thanks.
It is curious that the kWh and CO2e do not track anywhere near the same. I presume that reflects different energy sources. I'm not sure that NG really has lower carbon intensity than other fossils once methane release is accounted for but this report may not be using a full LCA. Perhaps this means that below poverty households are using resistance heating in the winter.
SageBrush
REJECT Fascism
I doubt it. 'Affluent' -- say median households have less children, and incomes way above 1.33x the FPL. the 90th percentile is ~ 5x FPL and income rises sharply thereafter
FPL is ~ $14,500 + $2,000 per dependent
This study sounds like a mishmash of fossil fuel sources. E.g, a kWh of electricity is ~ 12 cents averaged across the country but NG is ~ 1 - 2 cents a kWh and the authors may be presuming ~ 50% carbon intensity compared to average grid.
I am now confident in saying that I cannot make heads or tails out of this article.
Last edited:
SageBrush
REJECT Fascism
I'm not sure this is the place for my post, so if AGW corruption has its own thread I hope a moderator will move it.
Ohio House Speaker Arrested In Connection With $60 Million Bribery Scheme
I remember the discussion her about the OH decision to subsidize coal and nuclear last year. None of us understood the rationale, and for good reason
Now the big question is whether last year's choices will be cancelled.
Ohio House Speaker Arrested In Connection With $60 Million Bribery Scheme
I remember the discussion her about the OH decision to subsidize coal and nuclear last year. None of us understood the rationale, and for good reason
Now the big question is whether last year's choices will be cancelled.
JRP3
Hyperactive Member
Interesting look at liquid air for long term electricity storage. Comments say they claim 60-70% efficiency, seems as if it might be a promising large scale technology to help allow fully renewable grid.
SageBrush
REJECT Fascism
Does that include the turbine ?
Are they saving that 1.5 kWh goes in and ~ 1 kWh comes out ?
I'm having trouble accepting the claim because gas turbines reach ~ 60% efficiency and that is without a liquefaction step
Last edited:
JRP3
Hyperactive Member
I assume it's the round trip efficiency of the entire process. They don't have the inefficiency of combustion to deal with.
A look at the process
A look at the process
Will be a valuable renewable energy storage addition if this pans out. Having many hours to days of storage available for potential regional events that limit solar/wind inputs would be desirable. Of course, not being dependent on any water supply is also a big plus.
Will believe the claimed half the cost of Li-ion at scale when utilities start deploying this technology.
Technology
Will believe the claimed half the cost of Li-ion at scale when utilities start deploying this technology.
Technology
mspohr
Well-Known Member
Lots of waste heat from compression and liquefaction then waste heat again when you have to reverse the liquefaction and run it through a mechanical turbine.
Basic thermodynamics are against you all the way. Hard to get more than 50% round trip efficiency. (Same problems as hydrogen fuel.)
SageBrush
REJECT Fascism
I think that the waste heat is (optimally) stored for reuse when it is time to reverse the phase change. I don't know how efficient that can be, other than it will surely be less than 100% and over time the stored heat will escape to the environment.
My bigger question is how do they reach 70% overall efficiency when the best turbine in the world is ~ 63% ? Presuming the ~ 60% turbine efficiency is correct, the implication is that the heat removal during the compression phase has a COP of ~ 1.2. I'm not sure that is even in realm of possible at the temperatures involved, even though I do in general accept that heat pumps are magic.
Help, @nwdiver ?
Last edited:
Are you referring to turbines that involve combustion or all turbines in general? No combustion involved in this system.
Amateur here, but my understanding is turbines in closed systems that deal with fluids and gas phases are far more efficient in regards to mechanical energy-> electricity. For example:
The peak efficiency of a properly designed large hydraulic turbines can be as high as 95%.
HYDRAULIC TURBINES
Their turbine would have a high pressure gas phase input, so not sure how closely efficient that is to hydraulic.
Last edited:
mspohr
Well-Known Member
People want a greener, happier world now. But our politicians have other ideas
People want a greener, happier world now. But our politicians have other ideas | George Monbiot
Ours was no land of lost content, but a place in which lethal crises were gathering long before the pandemic struck. Alongside our many political and economic dysfunctions, normality meant accelerating the strangest and deepest predicament humankind has ever confronted: the collapse of our life-support systems.
The polls on this issue are also clear: we do not want to return to this madness. A YouGov survey suggests that eight out of 10 people want the government to prioritise health and wellbeing above economic growth during the pandemic, and six out of 10 would like it to stay that way when (or if) the virus abates
People want a greener, happier world now. But our politicians have other ideas | George Monbiot
Ours was no land of lost content, but a place in which lethal crises were gathering long before the pandemic struck. Alongside our many political and economic dysfunctions, normality meant accelerating the strangest and deepest predicament humankind has ever confronted: the collapse of our life-support systems.
The polls on this issue are also clear: we do not want to return to this madness. A YouGov survey suggests that eight out of 10 people want the government to prioritise health and wellbeing above economic growth during the pandemic, and six out of 10 would like it to stay that way when (or if) the virus abates
SageBrush
REJECT Fascism
That is my understanding also, which sounds awfully similar to my pea brain to a high pressure gas from combustion. I suppose I am saying that I don't think combustion is the lossy part but rather the step of using the high pressure to spin a blade.
Until someone tells me I am an idiot and explains things, I'm going with a a series of heat pumps that somehow or another gets the air down to liquid temperatures at an overall COP considerably over 1.0. At my level of understanding, magic is the only sound argument.
Last edited:
JRP3
Hyperactive Member
Hydrogen has different efficiency problems. I'm fairly sure there are ways to recover much of the waste heat in this process.
mspohr
Well-Known Member
It does look like they attempt to recover and store the waste heat (during compression) and the waste cooling (during expansion). I guess the total efficiency will depend on how much they can recover and reuse.
mspohr
Well-Known Member
Good question. I have not been able to find on CCGT, for example, the efficiency losses at each energy conversion step.
Found this.
According to this article, generator (final step) loss in thermal power generation systems is pretty small, so have to imagine in the cryo-energy storage system, they also have similarly minimal generator loss.
Efficiency loss may be predominantly at the "cold source loss" step, in this case when there are gas/liquid phase changes, and hence all the claims at scavenging/recycling what might otherwise be waste heat/cold.
https://iopscience.iop.org/article/10.1088/1742-6596/1449/1/012001/pdf
According to this article, generator (final step) loss in thermal power generation systems is pretty small, so have to imagine in the cryo-energy storage system, they also have similarly minimal generator loss.
Efficiency loss may be predominantly at the "cold source loss" step, in this case when there are gas/liquid phase changes, and hence all the claims at scavenging/recycling what might otherwise be waste heat/cold.
2.1 Boiler heat loss
Due to incomplete combustion and exhaust heat, the energy in the fuel cannot be completely transferred to the steam, thus causing energy loss. Modern boilers can attain an efficiency of around 90%-94%.
2.2 Cold source loss
As a heat engine operating between high and low temperature, the thermal power plant is bound to discharge a large amount of heat into the cold environment in order to fulfill its duty, resulting in huge energy loss. Energy loss from a cold source (5600C/5600C) caused by efficiency threshold stands at about 64%-67.57%. The actual thermal efficiency of a modern thermal power plant usually ranges between 35% and 49%.
2.3 Generator loss
Modern generators usually attain an efficiency of around 96%-99%.
As shown above, in the three main stages of thermal power generation, most of the energy loss comes from cold source loss. Thus, the key to improving the total efficiency of a thermal power plant lies at the steam cycle (where the cold source loss takes place).
Due to incomplete combustion and exhaust heat, the energy in the fuel cannot be completely transferred to the steam, thus causing energy loss. Modern boilers can attain an efficiency of around 90%-94%.
2.2 Cold source loss
As a heat engine operating between high and low temperature, the thermal power plant is bound to discharge a large amount of heat into the cold environment in order to fulfill its duty, resulting in huge energy loss. Energy loss from a cold source (5600C/5600C) caused by efficiency threshold stands at about 64%-67.57%. The actual thermal efficiency of a modern thermal power plant usually ranges between 35% and 49%.
2.3 Generator loss
Modern generators usually attain an efficiency of around 96%-99%.
As shown above, in the three main stages of thermal power generation, most of the energy loss comes from cold source loss. Thus, the key to improving the total efficiency of a thermal power plant lies at the steam cycle (where the cold source loss takes place).
https://iopscience.iop.org/article/10.1088/1742-6596/1449/1/012001/pdf
Similar threads
