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How to go green without failures and disasters? 17

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RedSnake

Electrical
Nov 7, 2020
10,535
SE
I think it is sad that we have thousands of years of accumulated knowledge and at least one hundred years of exponential technical development and we stil can’t utilize what we know.

I know it has much to do with politics, markets and peoples unwillingness to draw back on consumption and whether or not to believe in the scientists assessment of the climate change.
But I hope that we can keep that part of the discussion to a minimum and try to discuss the engineering and technical sides of things.

But since I am OP, I will start by not following my own advise. ;-)
By saying that, you do not need to be a scientist only a half dissent engineer, to know that if you put to many meta tablets in a toy steam engine and the pressure relief valve don’t work it will a eventually explode.[bomb]

Best Regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
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BW1 said:
An interesting irony and dirty unmentionable of renewable discussion stateside is that the political half constantly demonizing reliable/cheap fossil fuels as evil vs unreliable/costly solar & wind renewables have spent ~70 years pushing for the end of reliable/cheap hydroelectric, and in many areas have succeeded. The rural electric co-op that powers my folks' is up against them now. A local paper mill provided cheap power to the town from ~3 MW of hydro-generators from the 1930s until ~Y2k when it was forced to close and the town bought the site. Now the same outsiders who cost the townspeople half their jobs are demanding the town remove the hydros and buy off the larger grid which would increase prices from $0.025/kWh to $0.12/kWh, and require folks to convert homes from the common electric to fossil fuel heating. Apparently in an area legendary for sportfishing, nature, and green living, the fish are suffering a terrible tragedy that modern dam regulation cannot prevent.

The EU has also deemed water power / hydro-generator as not fully green since it destroys large nature values, which I agree with to some extent.
I would not like to see all water systems dammed up for water power, but the ones that are in place should remain the damage is already done.
Things built in the 30 where made to be robust and long-lived, effectiveness was maybe not the first priority.
Today I am shore that if same one would to have the guts and some long planning there is much do be done to make efficiency higher in such a power plant, more effective turbine wheels, low friction bearings , better generators etc. utilizing the water flow better.
It is some times since I saw any actual numbers on this but I am shore they can be found looking around for it.

BR A


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
Since for instans Texas and Australia have there high peak in the summer I guess it because of the air-conditioning systems, there would be a large market or opportunity for solarpanel driven air-conditioning units.
Lot of sun, lot of heat, lots of cool air ?
Or this..

BR A


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
How do we do ANYTHING without failures and disasters?
Any time we do something, we have some level of technology available to us - and then we make decisions based on immediate cost and so forth.
The advantages and drawbacks of any approach have to be made with what is actually available. Of course, if a technology has changes approaching, then the magnitude of those changes should be considered, as to whether the project should wait for those changes, allow the possibility of later upgrading, or simply going with existing tech.
We can hardly criticize the the technology of hydro dams build 50+ years ago except relative to the tech available at that time. If the system still performs as expected THEN, then that sounds like a success to me!
We humans are fallible, and are certainly not prescient.
Evap cooling is appropriate in some installations and wildly useless in conditions of high humidity. Much of the US gets hot and humid, so evaporative cooling isn't the first choice. Better than nothing, for folks who don't have much money of course.
Of course, hydro changes things behind a dam - but we change things every time we build.

Jay Maechtlen
 
JayMaechtlen said:
We can hardly criticize the the technology of hydro dams build 50+ years ago except relative to the tech available at that time. If the system still performs as expected THEN, then that sounds like a success to me!

Well I wasn’t critiquing the old technology, I myself work with 45 year old machines and they are much better than the new ones.

What I was trying to say is, that if you are going to change electrical production from hydropower to fossil fuels, there are other options that could be used to promote keeping it instead of just shutting it down.

And if someone would decide that a year from now, no AC units contactable to the grid where allowed to be sold or installed, do you not think that the market or the manufacturers would not be able solve that eventual problem?

Best Regards A


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
On some level I am nit-picking terminology, and also I don't think you are campaigning for removal of hydro plants.
Effectiveness, efficiency - how much more efficiency could be gained by new turbine wheels in existing hydro plants?
To refit when new wheels and high efficiency generators - how much improvement would you get, and how many years to pay back the investment?
Slightly off-topic, I know of someone on a team that repairs or refurbishes generation equipment - all big stuff, so it is all done on-site.
And chasing the last bit of efficiency - that can sure bite you in the ass - ask the operators of San Onofre, where a new heat exchanger should have given them a bit more performance, but instead failed and lead to retirement of that last reactor.

Jay Maechtlen
 
JayMaechtlen said:
On some level I am nit-picking terminology
[lol] Well I answered that at 20 Feb 21 21:33 in Taxas power issues. Windfarms getting iced up. thread. So you can find your answer there.

Effectiveness, efficiency - how much more efficiency could be gained by new turbine wheels in existing hydro plants?

I will try to find out for you.

how much improvement would you get, and how many years to pay back the investment?

Well at the factory where I work we go to great length to minimize electric consumption.
Of course we save by not having to pay for it.
For the ones producing the power it is different, but producing green energi is also something that sales better then non green if it is avalibul.
Since the goal is to be CO2 neutral in 25 years i guess that longer payback times might be necessary to reach that goal for some installation.

Best Regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
Most engineering failures have nothing to do with "Green" which is itself an ill defined term when used in the context of environmentally friendly. I suppose it is an eye of the beholder thing.
Wikipedia's Category:Engineering failures is not a comprehensive list. Brady Heywood a forensic engineer has published on the subject of Engineering Failure. His work is worth reading (
In regards to the Texas Power Debacle, if the marked does not create incentives for the needed reliability in off design conditions, then reliability in off design periods will be poor. In Texas the windmills cold weather performance was about as good as the more conventional plants. In the final analysis it is likely that the noise about "Green Power" being the cause of the problem will be found to be nonsense.

Texas needs to fund a Texas sized battery like the one in Bath County, Va.
We have a constant push at work to install "energy efficient lighting". We found the economics favor leaving the lighting as is until something else drives the replacement such as a renovation, group relamping, or age related ballast replacement. Similar logic likely applies to hydro turbines, as they do have a service life driven by impeller erosion and other factors.
 
The fabled "search for the optimum design considering all variables" will seldom if ever include extremes of any of the variables considered, yet the operating conditions inevitably will.
I.E. "Failure by design".

 
Thanks for the Wikipedia link - I should know of those articles, but hadn't thought of them.
Consideration of/planning for extremes - yeah...
Defining the requirement including unusual events and counting the cost of failure - these should be the very basics.
And preparation for extremes increases cost and may reduce performance/efficiency during ordinary operation.
It takes a real convincing presentation to sell features only needed in 100 year events.


Jay Maechtlen
 
I will return to your opening statement "I think it is sad that we have thousands of years of accumulated knowledge and at least one hundred years of exponential technical development and we stil can’t utilize what we know."

Can't we?
Being human, we will not be perfectly consistent. There being lots of competing priorities, what we implement may not be the best - due to financial political, or other factors.
But you can still get in a car and drive it, and it is a complete wonder compared to anything humans had 100 years ago, or even 50 years ago. We had residential electricity 100 years ago - in places.
You can live in the forest if you wish, with an axe and build a log cabin. And an outhouse. And use 1000 year old technology.
But I am really glad of what we have and what we do use.
We ain't doing all that bad!


Jay Maechtlen
 
FacEngrPE said:
Most engineering failures have nothing to do with "Green" which is itself an ill defined term when used in the context of environmentally friendly.

Well maybe I could have come up with a better headline, and explained better what my thinking was.

Which was if one is to be rude, that everybody is just complaining that it is not possible to have only wind power and solar cells and it will not work, and everything is lost if we can't burn coal and oil and natural gas and everything seems to a problem.

And then I thought stop whining! And shape up! You are engineers! So solve the problem!

But as a Swede, you can't say things like that, :-( we are almost born to be negotiator and the word arrogant does not exist in the Swedish dictionary and then one should always be "lagom" not too much not too little.
So that was me being "lagom".

So give me a good suggestion, and I can change the headline.

And no hard feelings from me.

(Edit) JayMaechtlen We ain't doing all that bad!
No we are not! I was being ironic ;-)

Best regards A
 
Is it even possible!
We are trying to replace 100's of millions of years of stored solar energy. The energy sources with that kind of energy density seem to be just nuclear (not that I think nuclear is anywhere sufficiently developed to actually replace hydrocarbons).

For every improvement there seems to be some unseen side effect that takes years to become publicly accepted (or legally proven). The wide spread uptake of efficient LED lighting has been suggested as contributing to the global decline in insect population (20 years ago at night I couldn't see the lights from any towns / city's from my house, now its 4 towns and city). Wind turbines kill birds, Submarine current Turbines kill fish, geothermal power releases heavy metals / cause earthquakes, no technology is without impact.

Reducing resource consumption, may have far worse side effects. A certain level of resource surplus is required to maintain technology, reduce that resource surplus and technology will be lost, which may lead to father loss of the resource surplus. There are plenty of examples of this from human history, the loss of ability of building ocean going boats by island bound natives (Tasmania, Easter Island, New Zealand, etc etc), multiply introductions of the Cross Bow into Europe from China, there were places in the USA that were so isolated they couldn't maintain the knowledge to keep weaving Looms functioning.


 
RedSnake said:
Since for instans Texas and Australia have there high peak in the summer I guess it because of the air-conditioning systems, there would be a large market or opportunity for solarpanel driven air-conditioning units.
Lot of sun, lot of heat, lots of cool air ?
Or this..

There's no free ride unfortunately.
From an economic point of view it used to make sense to install things like solar hot water, but now with the comparative cost of installing solar electric and an electric hot water heater versus single function solar hot water, its now better to do solar electricity and keep the electric hot water.
I would expect the same for air conditioning, its probably better to keep the existing air conditioning and use solar generated electricity, although that does allow use of the air conditioner without the renewable aspect. Also, for at least some of the areas in Australia with high solar resource, evaporative doesn't work as its already too humid to be effective. Some of the locations where evaporative is effective have water resource issues (e.g. Alice Springs).

EDMS Australia
 
No free ride even with large-scale solar. Recent studies have shown that using desert areas for massive solar farms can result in global climate change. This is due to heating differences in the albedo of solar cells and desert sand. Solar cells have a peak efficiency of about 15%. Sunlight not converted to electricity or reflected becomes heat.
And solar panels suffer from degradation over time. The reasons for degradation in the cells themselves is still not fully understood by semiconductor physicists.
 
Verymad said:
We are trying to replace 100's of millions of years of stored solar energy.

I worry about this one.

Despite all the talk of renewables taking over, fossil fuels still supply 80%+ of the worlds total power, same as it was 50 years ago. In absolute terms we’re using more fossil fuels than we ever have. This can’t last more than another few centuries, right?

It seems that we’re in the middle of a wild centuries-long party. Throwing our energy savings on the bonfire like there’s no tomorrow. When that nest egg saved up over millions of years starts to runs out, I suspect we’ll be facing a nasty hangover. That’ll be the real emergency.
 
My thought is, if global warming is such an imminent issue, like we're at a tipping point, how does spending massive resources to retool our entire world to save resources in the future improve the situation? Climate change is an industry of lies.
 
TugboatEng said:
I'd global warming is such an imminent issue, like we're at a tipping point, how does spending massive resources to retool our entire world to save resources in the future improve the situation?

It is possible to revers the CO[sub]2[/sub] contributing to global warming and and then balans it.
You can bind CO[sub]2[/sub]in for example in trees and in earth (biomaterial) like planting more trees building more in wood, less in cement which is very energy consuming, not destroying the earth with bad farming.
If one can managed that it's more a question of balancing the "system".

I am not suggesting that we stop using everything that is not renewable, maybe just to be smarter about it and use it less and when it is absolutely necessary.

BR A




“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
The scale of the problem is, we are looking for 136,761 Terawatt Hours of energy per year to replace the fossil fuels (out of 173 340 Terawatt Hours consumed). The problem with replacing that energy is it doesn't count the additional energy require to manufacture the new energy sources. Say if we achieve an average efficiently improvement in consumption & generation of 20% we are still looking at a 70% reduction in energy availability.

I can see generation possibilities that aren't being considered such as submarine sails, but all the sources being used are the most cost efficient otherwise the engineers with have gone with something else. All in all unless some bright spark can rewrite the laws of Physics so engineers can easily turn boring old rocks into energy, this starts to feel like an unsolvable problem (well at-least with in given constraints, include Biological warfare and its easy) or one of those engineering programs that fail because the critical piece of tech wasn't sufficiently developed.


 
in addition to going GREEN, future energy needs to become a person level. that is one needs to have the ability / device to be self substainable. I still see the use of micro grids that would allow the sharing to levelize. Now for energy density of that futuristic device, to me, even fossil fuel would not be sufficeint. So a magical source is needed, possible fission reactors.

In the short term, something that would have helped in a situation like frozen Texas would have been automotive vehicles equiped with electrical generation and battery storage. ie a hybrid, but with more generation than required just for transpertation. they should even be outfitted to interconnect. then the next step would be include an inverter that could use anothers excessive electrical into the fuel source. short term could be H2 / O2. Ultimately an isotope.

comment. sci-fiction to help steer the futue, I never had any problem accepting the possibility of faster than light travel, teleportation and instant stellar distance communications. But what I never can believe being possible is the battery pack used by a phasar!
 
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