What is the real limit of expanding solar+wind power?

Kaitzilla

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The power grid becomes unstable after > 20% of it runs on renewable energy.

They called me crazy 7 years ago. :old:
Obama Declares War on Coal June 2nd | Page 4 | CivFanatics Forums


I thought that solar + wind power can't go above 20% of an interconnected power grid without disaster.
(If a country consumes 10000MWh in a year, they better not get above 2000MWh from wind+solar)

Wind + Solar are fundamentally unreliable power sources.
(I like reliable hydro power, so I don't count it towards the 20% figure even if it is renewable energy)

I don't care if a country is 60% Wind+Solar if they are hooked up to another country that supplies it with endless amounts of power on cloudly and windless days.


Let's see where we were in 2020 since that is good data.

Europe-27 - Solar+Wind 19%
(All the countries connect together into effectively one power grid with various levels of connectivity)
EU Power Sector 2020 | Electricity Trends | Ember (ember-climate.org)

USA - Solar+Wind 11.6%
(All the lower 48 states, except Texas, connect together into an eastern and western power grid)
(*I can't figure out how to pull Texas out of that 11.6%. The real number should be a bit lower than 11.6% for the lower 48 states)
Renewables = 20.6% of US Electricity in 2020 - CleanTechnica

Texas - Solar+Wind 25%
Graphic Shows What Percentage of Texas' Energy Is Renewable (newsweek.com)

Australia - Solar+Wind 18%
Electricity generation | energy.gov.au



If my theory is correct, as of 2020 Texas should be a permanent yearly disaster.
Europe and Australia should be flirting with electricity problems.


I think this is currently an unresolvable problem.
Experiments where a third or a quarter of the grid run on this stuff, I can't make it work with my feeble brain.
Solar could be fixed if the entire world was connected into 1 power grid perhaps. :hmm:
Or if it was in space being beamed down.
Wind power could be fixed if there was a cheap way to store all that energy somehow at a massive scale.


I made this thread because this article here told me I'm quite wrong. :mad:
Three Myths About Renewable Energy and the Grid, Debunked - Yale E360

Renewable energy skeptics argue that because of their variability, wind and solar cannot be the foundation of a dependable electricity grid. But the expansion of renewables and new methods of energy management and storage can lead to a grid that is reliable and clean.

BY AMORY B. LOVINS AND M. V. RAMANA • DECEMBER 9, 2021

Gah!

We just have to use ___(has not been invented yet)___ gigantic amounts of cheap energy storage technology and we can build a power grid out of wind+solar in the next few years.
 
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You're incorrect, there's plenty of parallel grid modelling on real world conditions showing relatively little storage is required to balance wide area systems with very high renewables penetration. For example an ANU model a few years ago showed Australian demand in previous years could all be met in a system built entirely out of solar and wind power with new transmission lines and a lot of pumped hydro storage for stability. That's an extreme case because obviously you wouldn't wholesale flip over to just that, but it shows the technical ability does exist.

Grid operators are also now well into planning and preparing for much higher levels of penetration.

The limit is pretty much the rate of capital inflow, it's monetary, not technical.

Total renewables generation in Australia went from 24% in 2020 to 29% in 2021, which is a pretty big jump!

Those national figures you quote, though, include Western Australia and Northern Territory and a fair amount of off-grid generation by large mining and liquefied natural gas facilities. The Australian east coast grid is now at about 23% to 25% solar and wind generation for the 2021 calendar year.

Funnily enough, there is a bit of an electricity crisis here - a crisis of high prices caused by high fossil fuel prices and unreliable coal generation availability.
 
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Idk. Solar+Wind is actually eco-unfriendly imho. (Sorry to be a sceptic :( ) Even 25% still looks not that good compared to the consumption , and those windmill blades (engines , masts , etc. ) still need to be produced at some steel foundry I guess , unless uncle joe makes them in his tool's shed xD Solar panels too.) Besides they occupy a huge amount of space forcing animals to die off or relocate to god knows where and forests to be chopped, razed to the ground in order to put a windmills or solar panels there - they are not space efficient at all ! In my subjective opinion atomic power is the only way to go . It will sure require a lot of CO2 released into the atmosphere to be set up once it is set up it will be far more efficient and eco-friendly than any of those windmills or solar panel "farms" as far as the eye can see.
 
You're incorrect, there's plenty of parallel grid modelling on real world conditions showing relatively little storage is required to balance wide area systems with very high renewables penetration. For example an ANU model a few years ago showed Australian demand in previous years could all be met in a system built entirely out of solar and wind power with new transmission lines and a lot of pumped hydro storage for stability. That's an extreme case because obviously you wouldn't wholesale flip over to just that, but it shows the technical ability does exist.

Grid operators are also now well into planning and preparing for much higher levels of penetration.

The limit is pretty much the rate of capital inflow, it's monetary, not technical.

Total renewables generation in Australia went from 24% in 2020 to 29% in 2021, which is a pretty big jump!

Those national figures you quote, though, include Western Australia and Northern Territory and a fair amount of off-grid generation by large mining and liquefied natural gas facilities. The Australian east coast grid is now at about 23% to 25% solar and wind generation for the 2021 calendar year.

Funnily enough, there is a bit of an electricity crisis here - a crisis of high prices caused by high fossil fuel prices and unreliable coal generation availability.

Well, I guess my whole argument rests on debating that pumped hydro storage.

Sure it works and exists in models, but can it exist in real life?
Will the environmentalists allow it to be built?
Can a grid really depend on it for long amounts of time?

Once a grid goes above 20% wind+solar (in total energy consumed by all the grid customers), the coal and the rest are just there to back up the clean energy (when pumped hydro energy runs out) and thus don't make any money I would imagine.
Why build or maintain money losers?
Thus the grid ends up crashing anyway and everyone points fingers at the fossil fuel stuff that is getting gradually phased out, but I still blame that wonderful wind+solar in part.

I'm still skeptical about energy storage on a vast scale being economical enough to replace whatever currently backs up solar + wind on dark windless days.

the Australian east coast grid is now at about 23% to 25% solar and wind generation for 2021 calendar year.

:eek:

(*Squints*) Well, the grid still seems to be working there right now, which means I'm wrong so far.

I'll pay attention to this thread for another 3 years and if everything is fine I'll update this thread to admit I was wrong.
 
The pumped hydro storage sites was just what made the model work in 2017 to demonstrate that the last few percent of 100% renewables was technically possible.

Run of river storage stuff shouldn't be too difficult but I don't think the market is trending that strongly in that direction.

In reality since nobody can flip an entire continent to 100% renewables instantaneously, I don't think there will be that much of it. By that point it's more likely to be a mix of existing hydro, batteries, EV charge timing, demand management and the like.
 
Oh you can also follow it in near real time at Open NEM.

Here is the last year, solar and wind up to 25%.

Screenshot_2022_0714_115749.jpg


And in December about 30%
Screenshot_2022_0714_120309.jpg
 
So Australia has no Atomic power plants ? I've always somehow imagined that they would have them.
 
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Australia has lots of deserts and plenty of sun but what about countries with no such conditions ?
 
Idk. Solar+Wind is actually eco-unfriendly imho. (Sorry to be a sceptic :( ) Even 25% still looks not that good compared to the consumption , and those windmill blades (engines , masts , etc. ) still need to be produced at some steel foundry I guess , unless uncle joe makes them in his tool's shed xD Solar panels too.) Besides they occupy a huge amount of space forcing animals to die off or relocate to god knows where and forests to be chopped, razed to the ground in order to put a windmills or solar panels there - they are not space efficient at all ! In my subjective opinion atomic power is the only way to go . It will sure require a lot of CO2 released into the atmosphere to be set up once it is set up it will be far more efficient and eco-friendly than any of those windmills or solar panel "farms" as far as the eye can see.

Nuclear would solve global warming at great cost sure.

And then every country on earth would have oodles of stuff to make atomic bombs, radioactive waste with no place to store it, and a nonzero chance every day to irradiate hundreds of square kilometers for a few centuries.

This will only get consideration once we start losing coastal cities to the ocean.
 
Nuclear would solve global warming at great cost sure.

And then every country on earth would have oodles of stuff to make atomic bombs, radioactive waste with no place to store it, and a nonzero chance every day to irradiate hundreds of square kilometers for a few centuries.

This will only get consideration once we start losing coastal cities to the ocean.

Also takes 15 years to build a new plant, usually at double whatever cost they initially plan, which was already well above various renewable alternatives. Not a smart use of public funds.
 
Probably depends a lot on whether you’re talking about Alaska or Hawaii. In my area you generate about an order of magnitude more power in the summer than you do in the winter with solar, so averaging that over a year doesn’t tell you much about infrastructure needs.

(I was recently doing the math on exterior solar lighting, which is even worse, because not only do you generate only a tenth of the power in the winter, your batteries only hold half as much energy and you need to power your lights for twice as long.)

And then every country on earth would have oodles of stuff to make atomic bombs, radioactive waste with no place to store it, and a nonzero chance every day to irradiate hundreds of square kilometers for a few centuries.

TBF you could cover well over half the world’s energy needs with only existing nuclear and nuclear latent powers having access to nuclear plants.
 
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There is no limit.

What currently hamstrings us is the lack of a universal grid. Sun in Spain piped to Norwegian home, Nuclear power routed to East Africa.

Sun, wind, tide are all in abundance, if we can just get it to where its needed.

I am a fan of the sand battery concept to store energy.
 
For wind power, the limit is mostly economical. With a large enough grid, there will always be some wind somewhere. So it is only a question of how much you overbuild generation and transmission capacity. Do we want to build wind turbines that are only necessary twice a year?

Solar us different, because the daily variability is much higher and in very northern/southern latitudes, you also have a large seasonal variability. The limit will depend on the location. Solar would be ideal for powering air conditioning, because you need it the most, when the sun is shining.
 
The two key factors are grid interconnectivity (the whole of northern Europe is interconnected to the same grid) and energy storage.

Interconnectivity assures that there is always enough supply of electricity to meet demand, despite not all connected sectors producing electricity all the time due to weather, maintenance etc.
Energy storage can store surplus electricity and then release it into the grid when the demand arises. It's only now that engineers are making the technological breakthroughs needed, to make huge scale energy storage from renewables a reality.
 
Cooling now reached mid 20's. No clouds.

IMG_20221228_151928.jpg

IMG_20221228_151925.jpg

Heat pumps on 16.
 
As I see it there are two main challenges.

One is that it won't always be sunny and it won't always be windy. Larger transmission grids reduce the risks here; there will always be wind somewhere and it will always be sunny somewhere. Underinvestment in transmission grids is not a new thing; T. Boone Pickens wanted to build a giant wind farm in the Texas Panhandle in 2009 but had to call it off because the transmission lines to move the power elsewhere didn't exist, and it would generate too much power for the sparsely-populated Panhandle to use. But the needle has slowly been moving on transmission grid investment. If wind or solar costs 33% less than coal or natural gas (to use an off the cuff figure), you can invest part of that in improving the grid and still come out ahead.

Places like Alaska will have challenges with solar in the winter due to lack of sunlight, but I'm not aware of anywhere that doesn't get wind for months at a time. Fortunately, some areas with short days during the winter have other renewable options such as hydro (Norway) and geothermal (Iceland).

The other challenge is keeping the grid frequency stable as generation varies.

This is an area where backup sources such as pumped storage and battery can even out fluctuations. So can natural gas or coal peaker plants, but battery is quicker than either and thus offers an advantage even if you had an entirely non-renewable grid.

It's also important to keep the grid frequency stable for reasons other than renewables; storm damage or war damage can knock out parts of the grid, causing the grid frequency to move out of balance. This is a risk in Europe currently, as Ukraine has been integrated into the European grid, but Russia keeps destroying infrastructure, stressing the European grid every time it happens. It's a testament to modern engineering that the effects haven't spread farther than they have; Russian artillery will cause fluctuations much more quickly than the sunset or the wind tapering off.

All in all, I have faith in the ingenuity of humanity and the economics of solar and wind that we can get well beyond 20%, possibly all the way to 100%. We might have to be overprovisioned in the summer to have enough solar in the winter. We'll want wider grids where feasible to average things out. It will be easier if we have some clean baseline energy, whether that's fission, geothermal, hydro, or potentially fusion in the future. But I agree with those who said that at this point it's primarily a monetary investment problem, perhaps with a side of "the windmill factories can only build so many windmills per year."

------

Side note, I knew Australia mined a lot of coal, but I had no idea Australia burned so much coal for electricity! To be fair, Ohio was doing the same until about 10 years ago when natural gas took off, and Australia has more wind and solar even if the amount of coal means the grid might not net cleaner yet.
 
They called me crazy 7 years ago. :old:
Obama Declares War on Coal June 2nd | Page 4 | CivFanatics Forums


I thought that solar + wind power can't go above 20% of an interconnected power grid without disaster.
(If a country consumes 10000MWh in a year, they better not get above 2000MWh from wind+solar)

Wind + Solar are fundamentally unreliable power sources.
(I like reliable hydro power, so I don't count it towards the 20% figure even if it is renewable energy)

I don't care if a country is 60% Wind+Solar if they are hooked up to another country that supplies it with endless amounts of power on cloudly and windless days.


Let's see where we were in 2020 since that is good data.

Europe-27 - Solar+Wind 19%
(All the countries connect together into effectively one power grid with various levels of connectivity)
EU Power Sector 2020 | Electricity Trends | Ember (ember-climate.org)

USA - Solar+Wind 11.6%
(All the lower 48 states, except Texas, connect together into an eastern and western power grid)
(*I can't figure out how to pull Texas out of that 11.6%. The real number should be a bit lower than 11.6% for the lower 48 states)
Renewables = 20.6% of US Electricity in 2020 - CleanTechnica

Texas - Solar+Wind 25%
Graphic Shows What Percentage of Texas' Energy Is Renewable (newsweek.com)

Australia - Solar+Wind 18%
Electricity generation | energy.gov.au



If my theory is correct, as of 2020 Texas should be a permanent yearly disaster.
Europe and Australia should be flirting with electricity problems.


I think this is currently an unresolvable problem.
Experiments where a third or a quarter of the grid run on this stuff, I can't make it work with my feeble brain.
Solar could be fixed if the entire world was connected into 1 power grid perhaps. :hmm:
Or if it was in space being beamed down.
Wind power could be fixed if there was a cheap way to store all that energy somehow at a massive scale.


I made this thread because this article here told me I'm quite wrong. :mad:
Three Myths About Renewable Energy and the Grid, Debunked - Yale E360



Gah!

We just have to use ___(has not been invented yet)___ gigantic amounts of cheap energy storage technology and we can build a power grid out of wind+solar in the next few years.

What if a country runs 90% on wind+solar but also has alert coal-based energy facilities ready for action any minute?
And they take over once any weather disturbance begins?

Isn't it better than just relying on 20% wind+solar all of the year?
 
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Coal is terrible at that flex load following role, which is something that does exist in traditional low renewables grids. Usually it's hydro or gas that does it.
 
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